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Posted to commits@tapestry.apache.org by th...@apache.org on 2018/11/29 00:34:21 UTC
[34/46] tapestry-5 git commit: TAP5-2588: upgrading from ASM 6 to 7
for Java 9+ support
http://git-wip-us.apache.org/repos/asf/tapestry-5/blob/1c71aec7/plastic/src/external/java/org/apache/tapestry5/internal/plastic/asm/SymbolTable.java
----------------------------------------------------------------------
diff --git a/plastic/src/external/java/org/apache/tapestry5/internal/plastic/asm/SymbolTable.java b/plastic/src/external/java/org/apache/tapestry5/internal/plastic/asm/SymbolTable.java
new file mode 100755
index 0000000..e6574bb
--- /dev/null
+++ b/plastic/src/external/java/org/apache/tapestry5/internal/plastic/asm/SymbolTable.java
@@ -0,0 +1,1318 @@
+// ASM: a very small and fast Java bytecode manipulation framework
+// Copyright (c) 2000-2011 INRIA, France Telecom
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions
+// are met:
+// 1. Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the distribution.
+// 3. Neither the name of the copyright holders nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+// THE POSSIBILITY OF SUCH DAMAGE.
+package org.apache.tapestry5.internal.plastic.asm;
+
+/**
+ * The constant pool entries, the BootstrapMethods attribute entries and the (ASM specific) type
+ * table entries of a class.
+ *
+ * @see <a href="https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.4">JVMS
+ * 4.4</a>
+ * @see <a href="https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.7.23">JVMS
+ * 4.7.23</a>
+ * @author Eric Bruneton
+ */
+final class SymbolTable {
+
+ /**
+ * The ClassWriter to which this SymbolTable belongs. This is only used to get access to {@link
+ * ClassWriter#getCommonSuperClass} and to serialize custom attributes with {@link
+ * Attribute#write}.
+ */
+ final ClassWriter classWriter;
+
+ /**
+ * The ClassReader from which this SymbolTable was constructed, or {@literal null} if it was
+ * constructed from scratch.
+ */
+ private final ClassReader sourceClassReader;
+
+ /** The major version number of the class to which this symbol table belongs. */
+ private int majorVersion;
+
+ /** The internal name of the class to which this symbol table belongs. */
+ private String className;
+
+ /**
+ * The total number of {@link Entry} instances in {@link #entries}. This includes entries that are
+ * accessible (recursively) via {@link Entry#next}.
+ */
+ private int entryCount;
+
+ /**
+ * A hash set of all the entries in this SymbolTable (this includes the constant pool entries, the
+ * bootstrap method entries and the type table entries). Each {@link Entry} instance is stored at
+ * the array index given by its hash code modulo the array size. If several entries must be stored
+ * at the same array index, they are linked together via their {@link Entry#next} field. The
+ * factory methods of this class make sure that this table does not contain duplicated entries.
+ */
+ private Entry[] entries;
+
+ /**
+ * The number of constant pool items in {@link #constantPool}, plus 1. The first constant pool
+ * item has index 1, and long and double items count for two items.
+ */
+ private int constantPoolCount;
+
+ /**
+ * The content of the ClassFile's constant_pool JVMS structure corresponding to this SymbolTable.
+ * The ClassFile's constant_pool_count field is <i>not</i> included.
+ */
+ private ByteVector constantPool;
+
+ /**
+ * The number of bootstrap methods in {@link #bootstrapMethods}. Corresponds to the
+ * BootstrapMethods_attribute's num_bootstrap_methods field value.
+ */
+ private int bootstrapMethodCount;
+
+ /**
+ * The content of the BootstrapMethods attribute 'bootstrap_methods' array corresponding to this
+ * SymbolTable. Note that the first 6 bytes of the BootstrapMethods_attribute, and its
+ * num_bootstrap_methods field, are <i>not</i> included.
+ */
+ private ByteVector bootstrapMethods;
+
+ /**
+ * The actual number of elements in {@link #typeTable}. These elements are stored from index 0 to
+ * typeCount (excluded). The other array entries are empty.
+ */
+ private int typeCount;
+
+ /**
+ * An ASM specific type table used to temporarily store internal names that will not necessarily
+ * be stored in the constant pool. This type table is used by the control flow and data flow
+ * analysis algorithm used to compute stack map frames from scratch. This array stores {@link
+ * Symbol#TYPE_TAG} and {@link Symbol#UNINITIALIZED_TYPE_TAG}) Symbol. The type symbol at index
+ * {@code i} has its {@link Symbol#index} equal to {@code i} (and vice versa).
+ */
+ private Entry[] typeTable;
+
+ /**
+ * Constructs a new, empty SymbolTable for the given ClassWriter.
+ *
+ * @param classWriter a ClassWriter.
+ */
+ SymbolTable(final ClassWriter classWriter) {
+ this.classWriter = classWriter;
+ this.sourceClassReader = null;
+ this.entries = new Entry[256];
+ this.constantPoolCount = 1;
+ this.constantPool = new ByteVector();
+ }
+
+ /**
+ * Constructs a new SymbolTable for the given ClassWriter, initialized with the constant pool and
+ * bootstrap methods of the given ClassReader.
+ *
+ * @param classWriter a ClassWriter.
+ * @param classReader the ClassReader whose constant pool and bootstrap methods must be copied to
+ * initialize the SymbolTable.
+ */
+ SymbolTable(final ClassWriter classWriter, final ClassReader classReader) {
+ this.classWriter = classWriter;
+ this.sourceClassReader = classReader;
+
+ // Copy the constant pool binary content.
+ byte[] inputBytes = classReader.b;
+ int constantPoolOffset = classReader.getItem(1) - 1;
+ int constantPoolLength = classReader.header - constantPoolOffset;
+ constantPoolCount = classReader.getItemCount();
+ constantPool = new ByteVector(constantPoolLength);
+ constantPool.putByteArray(inputBytes, constantPoolOffset, constantPoolLength);
+
+ // Add the constant pool items in the symbol table entries. Reserve enough space in 'entries' to
+ // avoid too many hash set collisions (entries is not dynamically resized by the addConstant*
+ // method calls below), and to account for bootstrap method entries.
+ entries = new Entry[constantPoolCount * 2];
+ char[] charBuffer = new char[classReader.getMaxStringLength()];
+ boolean hasBootstrapMethods = false;
+ int itemIndex = 1;
+ while (itemIndex < constantPoolCount) {
+ int itemOffset = classReader.getItem(itemIndex);
+ int itemTag = inputBytes[itemOffset - 1];
+ int nameAndTypeItemOffset;
+ switch (itemTag) {
+ case Symbol.CONSTANT_FIELDREF_TAG:
+ case Symbol.CONSTANT_METHODREF_TAG:
+ case Symbol.CONSTANT_INTERFACE_METHODREF_TAG:
+ nameAndTypeItemOffset =
+ classReader.getItem(classReader.readUnsignedShort(itemOffset + 2));
+ addConstantMemberReference(
+ itemIndex,
+ itemTag,
+ classReader.readClass(itemOffset, charBuffer),
+ classReader.readUTF8(nameAndTypeItemOffset, charBuffer),
+ classReader.readUTF8(nameAndTypeItemOffset + 2, charBuffer));
+ break;
+ case Symbol.CONSTANT_INTEGER_TAG:
+ case Symbol.CONSTANT_FLOAT_TAG:
+ addConstantIntegerOrFloat(itemIndex, itemTag, classReader.readInt(itemOffset));
+ break;
+ case Symbol.CONSTANT_NAME_AND_TYPE_TAG:
+ addConstantNameAndType(
+ itemIndex,
+ classReader.readUTF8(itemOffset, charBuffer),
+ classReader.readUTF8(itemOffset + 2, charBuffer));
+ break;
+ case Symbol.CONSTANT_LONG_TAG:
+ case Symbol.CONSTANT_DOUBLE_TAG:
+ addConstantLongOrDouble(itemIndex, itemTag, classReader.readLong(itemOffset));
+ break;
+ case Symbol.CONSTANT_UTF8_TAG:
+ addConstantUtf8(itemIndex, classReader.readUtf(itemIndex, charBuffer));
+ break;
+ case Symbol.CONSTANT_METHOD_HANDLE_TAG:
+ int memberRefItemOffset =
+ classReader.getItem(classReader.readUnsignedShort(itemOffset + 1));
+ nameAndTypeItemOffset =
+ classReader.getItem(classReader.readUnsignedShort(memberRefItemOffset + 2));
+ addConstantMethodHandle(
+ itemIndex,
+ classReader.readByte(itemOffset),
+ classReader.readClass(memberRefItemOffset, charBuffer),
+ classReader.readUTF8(nameAndTypeItemOffset, charBuffer),
+ classReader.readUTF8(nameAndTypeItemOffset + 2, charBuffer));
+ break;
+ case Symbol.CONSTANT_DYNAMIC_TAG:
+ case Symbol.CONSTANT_INVOKE_DYNAMIC_TAG:
+ hasBootstrapMethods = true;
+ nameAndTypeItemOffset =
+ classReader.getItem(classReader.readUnsignedShort(itemOffset + 2));
+ addConstantDynamicOrInvokeDynamicReference(
+ itemTag,
+ itemIndex,
+ classReader.readUTF8(nameAndTypeItemOffset, charBuffer),
+ classReader.readUTF8(nameAndTypeItemOffset + 2, charBuffer),
+ classReader.readUnsignedShort(itemOffset));
+ break;
+ case Symbol.CONSTANT_STRING_TAG:
+ case Symbol.CONSTANT_CLASS_TAG:
+ case Symbol.CONSTANT_METHOD_TYPE_TAG:
+ case Symbol.CONSTANT_MODULE_TAG:
+ case Symbol.CONSTANT_PACKAGE_TAG:
+ addConstantUtf8Reference(
+ itemIndex, itemTag, classReader.readUTF8(itemOffset, charBuffer));
+ break;
+ default:
+ throw new IllegalArgumentException();
+ }
+ itemIndex +=
+ (itemTag == Symbol.CONSTANT_LONG_TAG || itemTag == Symbol.CONSTANT_DOUBLE_TAG) ? 2 : 1;
+ }
+
+ // Copy the BootstrapMethods, if any.
+ if (hasBootstrapMethods) {
+ copyBootstrapMethods(classReader, charBuffer);
+ }
+ }
+
+ /**
+ * Read the BootstrapMethods 'bootstrap_methods' array binary content and add them as entries of
+ * the SymbolTable.
+ *
+ * @param classReader the ClassReader whose bootstrap methods must be copied to initialize the
+ * SymbolTable.
+ * @param charBuffer a buffer used to read strings in the constant pool.
+ */
+ private void copyBootstrapMethods(final ClassReader classReader, final char[] charBuffer) {
+ // Find attributOffset of the 'bootstrap_methods' array.
+ byte[] inputBytes = classReader.b;
+ int currentAttributeOffset = classReader.getFirstAttributeOffset();
+ for (int i = classReader.readUnsignedShort(currentAttributeOffset - 2); i > 0; --i) {
+ String attributeName = classReader.readUTF8(currentAttributeOffset, charBuffer);
+ if (Constants.BOOTSTRAP_METHODS.equals(attributeName)) {
+ bootstrapMethodCount = classReader.readUnsignedShort(currentAttributeOffset + 6);
+ break;
+ }
+ currentAttributeOffset += 6 + classReader.readInt(currentAttributeOffset + 2);
+ }
+ if (bootstrapMethodCount > 0) {
+ // Compute the offset and the length of the BootstrapMethods 'bootstrap_methods' array.
+ int bootstrapMethodsOffset = currentAttributeOffset + 8;
+ int bootstrapMethodsLength = classReader.readInt(currentAttributeOffset + 2) - 2;
+ bootstrapMethods = new ByteVector(bootstrapMethodsLength);
+ bootstrapMethods.putByteArray(inputBytes, bootstrapMethodsOffset, bootstrapMethodsLength);
+
+ // Add each bootstrap method in the symbol table entries.
+ int currentOffset = bootstrapMethodsOffset;
+ for (int i = 0; i < bootstrapMethodCount; i++) {
+ int offset = currentOffset - bootstrapMethodsOffset;
+ int bootstrapMethodRef = classReader.readUnsignedShort(currentOffset);
+ currentOffset += 2;
+ int numBootstrapArguments = classReader.readUnsignedShort(currentOffset);
+ currentOffset += 2;
+ int hashCode = classReader.readConst(bootstrapMethodRef, charBuffer).hashCode();
+ while (numBootstrapArguments-- > 0) {
+ int bootstrapArgument = classReader.readUnsignedShort(currentOffset);
+ currentOffset += 2;
+ hashCode ^= classReader.readConst(bootstrapArgument, charBuffer).hashCode();
+ }
+ add(new Entry(i, Symbol.BOOTSTRAP_METHOD_TAG, offset, hashCode & 0x7FFFFFFF));
+ }
+ }
+ }
+
+ /**
+ * Returns the ClassReader from which this SymbolTable was constructed.
+ *
+ * @return the ClassReader from which this SymbolTable was constructed, or {@literal null} if it
+ * was constructed from scratch.
+ */
+ ClassReader getSource() {
+ return sourceClassReader;
+ }
+
+ /**
+ * Returns the major version of the class to which this symbol table belongs.
+ *
+ * @return the major version of the class to which this symbol table belongs.
+ */
+ int getMajorVersion() {
+ return majorVersion;
+ }
+
+ /**
+ * Returns the internal name of the class to which this symbol table belongs.
+ *
+ * @return the internal name of the class to which this symbol table belongs.
+ */
+ String getClassName() {
+ return className;
+ }
+
+ /**
+ * Sets the major version and the name of the class to which this symbol table belongs. Also adds
+ * the class name to the constant pool.
+ *
+ * @param majorVersion a major ClassFile version number.
+ * @param className an internal class name.
+ * @return the constant pool index of a new or already existing Symbol with the given class name.
+ */
+ int setMajorVersionAndClassName(final int majorVersion, final String className) {
+ this.majorVersion = majorVersion;
+ this.className = className;
+ return addConstantClass(className).index;
+ }
+
+ /**
+ * Returns the number of items in this symbol table's constant_pool array (plus 1).
+ *
+ * @return the number of items in this symbol table's constant_pool array (plus 1).
+ */
+ int getConstantPoolCount() {
+ return constantPoolCount;
+ }
+
+ /**
+ * Returns the length in bytes of this symbol table's constant_pool array.
+ *
+ * @return the length in bytes of this symbol table's constant_pool array.
+ */
+ int getConstantPoolLength() {
+ return constantPool.length;
+ }
+
+ /**
+ * Puts this symbol table's constant_pool array in the given ByteVector, preceded by the
+ * constant_pool_count value.
+ *
+ * @param output where the JVMS ClassFile's constant_pool array must be put.
+ */
+ void putConstantPool(final ByteVector output) {
+ output.putShort(constantPoolCount).putByteArray(constantPool.data, 0, constantPool.length);
+ }
+
+ /**
+ * Returns the size in bytes of this symbol table's BootstrapMethods attribute. Also adds the
+ * attribute name in the constant pool.
+ *
+ * @return the size in bytes of this symbol table's BootstrapMethods attribute.
+ */
+ int computeBootstrapMethodsSize() {
+ if (bootstrapMethods != null) {
+ addConstantUtf8(Constants.BOOTSTRAP_METHODS);
+ return 8 + bootstrapMethods.length;
+ } else {
+ return 0;
+ }
+ }
+
+ /**
+ * Puts this symbol table's BootstrapMethods attribute in the given ByteVector. This includes the
+ * 6 attribute header bytes and the num_bootstrap_methods value.
+ *
+ * @param output where the JVMS BootstrapMethods attribute must be put.
+ */
+ void putBootstrapMethods(final ByteVector output) {
+ if (bootstrapMethods != null) {
+ output
+ .putShort(addConstantUtf8(Constants.BOOTSTRAP_METHODS))
+ .putInt(bootstrapMethods.length + 2)
+ .putShort(bootstrapMethodCount)
+ .putByteArray(bootstrapMethods.data, 0, bootstrapMethods.length);
+ }
+ }
+
+ // -----------------------------------------------------------------------------------------------
+ // Generic symbol table entries management.
+ // -----------------------------------------------------------------------------------------------
+
+ /**
+ * Returns the list of entries which can potentially have the given hash code.
+ *
+ * @param hashCode a {@link Entry#hashCode} value.
+ * @return the list of entries which can potentially have the given hash code. The list is stored
+ * via the {@link Entry#next} field.
+ */
+ private Entry get(final int hashCode) {
+ return entries[hashCode % entries.length];
+ }
+
+ /**
+ * Puts the given entry in the {@link #entries} hash set. This method does <i>not</i> check
+ * whether {@link #entries} already contains a similar entry or not. {@link #entries} is resized
+ * if necessary to avoid hash collisions (multiple entries needing to be stored at the same {@link
+ * #entries} array index) as much as possible, with reasonable memory usage.
+ *
+ * @param entry an Entry (which must not already be contained in {@link #entries}).
+ * @return the given entry
+ */
+ private Entry put(final Entry entry) {
+ if (entryCount > (entries.length * 3) / 4) {
+ int currentCapacity = entries.length;
+ int newCapacity = currentCapacity * 2 + 1;
+ Entry[] newEntries = new Entry[newCapacity];
+ for (int i = currentCapacity - 1; i >= 0; --i) {
+ Entry currentEntry = entries[i];
+ while (currentEntry != null) {
+ int newCurrentEntryIndex = currentEntry.hashCode % newCapacity;
+ Entry nextEntry = currentEntry.next;
+ currentEntry.next = newEntries[newCurrentEntryIndex];
+ newEntries[newCurrentEntryIndex] = currentEntry;
+ currentEntry = nextEntry;
+ }
+ }
+ entries = newEntries;
+ }
+ entryCount++;
+ int index = entry.hashCode % entries.length;
+ entry.next = entries[index];
+ return entries[index] = entry;
+ }
+
+ /**
+ * Adds the given entry in the {@link #entries} hash set. This method does <i>not</i> check
+ * whether {@link #entries} already contains a similar entry or not, and does <i>not</i> resize
+ * {@link #entries} if necessary.
+ *
+ * @param entry an Entry (which must not already be contained in {@link #entries}).
+ */
+ private void add(final Entry entry) {
+ entryCount++;
+ int index = entry.hashCode % entries.length;
+ entry.next = entries[index];
+ entries[index] = entry;
+ }
+
+ // -----------------------------------------------------------------------------------------------
+ // Constant pool entries management.
+ // -----------------------------------------------------------------------------------------------
+
+ /**
+ * Adds a number or string constant to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param value the value of the constant to be added to the constant pool. This parameter must be
+ * an {@link Integer}, {@link Byte}, {@link Character}, {@link Short}, {@link Boolean}, {@link
+ * Float}, {@link Long}, {@link Double}, {@link String}, {@link Type} or {@link Handle}.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstant(final Object value) {
+ if (value instanceof Integer) {
+ return addConstantInteger(((Integer) value).intValue());
+ } else if (value instanceof Byte) {
+ return addConstantInteger(((Byte) value).intValue());
+ } else if (value instanceof Character) {
+ return addConstantInteger(((Character) value).charValue());
+ } else if (value instanceof Short) {
+ return addConstantInteger(((Short) value).intValue());
+ } else if (value instanceof Boolean) {
+ return addConstantInteger(((Boolean) value).booleanValue() ? 1 : 0);
+ } else if (value instanceof Float) {
+ return addConstantFloat(((Float) value).floatValue());
+ } else if (value instanceof Long) {
+ return addConstantLong(((Long) value).longValue());
+ } else if (value instanceof Double) {
+ return addConstantDouble(((Double) value).doubleValue());
+ } else if (value instanceof String) {
+ return addConstantString((String) value);
+ } else if (value instanceof Type) {
+ Type type = (Type) value;
+ int typeSort = type.getSort();
+ if (typeSort == Type.OBJECT) {
+ return addConstantClass(type.getInternalName());
+ } else if (typeSort == Type.METHOD) {
+ return addConstantMethodType(type.getDescriptor());
+ } else { // type is a primitive or array type.
+ return addConstantClass(type.getDescriptor());
+ }
+ } else if (value instanceof Handle) {
+ Handle handle = (Handle) value;
+ return addConstantMethodHandle(
+ handle.getTag(),
+ handle.getOwner(),
+ handle.getName(),
+ handle.getDesc(),
+ handle.isInterface());
+ } else if (value instanceof ConstantDynamic) {
+ ConstantDynamic constantDynamic = (ConstantDynamic) value;
+ return addConstantDynamic(
+ constantDynamic.getName(),
+ constantDynamic.getDescriptor(),
+ constantDynamic.getBootstrapMethod(),
+ constantDynamic.getBootstrapMethodArgumentsUnsafe());
+ } else {
+ throw new IllegalArgumentException("value " + value);
+ }
+ }
+
+ /**
+ * Adds a CONSTANT_Class_info to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param value the internal name of a class.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantClass(final String value) {
+ return addConstantUtf8Reference(Symbol.CONSTANT_CLASS_TAG, value);
+ }
+
+ /**
+ * Adds a CONSTANT_Fieldref_info to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param owner the internal name of a class.
+ * @param name a field name.
+ * @param descriptor a field descriptor.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantFieldref(final String owner, final String name, final String descriptor) {
+ return addConstantMemberReference(Symbol.CONSTANT_FIELDREF_TAG, owner, name, descriptor);
+ }
+
+ /**
+ * Adds a CONSTANT_Methodref_info or CONSTANT_InterfaceMethodref_info to the constant pool of this
+ * symbol table. Does nothing if the constant pool already contains a similar item.
+ *
+ * @param owner the internal name of a class.
+ * @param name a method name.
+ * @param descriptor a method descriptor.
+ * @param isInterface whether owner is an interface or not.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantMethodref(
+ final String owner, final String name, final String descriptor, final boolean isInterface) {
+ int tag = isInterface ? Symbol.CONSTANT_INTERFACE_METHODREF_TAG : Symbol.CONSTANT_METHODREF_TAG;
+ return addConstantMemberReference(tag, owner, name, descriptor);
+ }
+
+ /**
+ * Adds a CONSTANT_Fieldref_info, CONSTANT_Methodref_info or CONSTANT_InterfaceMethodref_info to
+ * the constant pool of this symbol table. Does nothing if the constant pool already contains a
+ * similar item.
+ *
+ * @param tag one of {@link Symbol#CONSTANT_FIELDREF_TAG}, {@link Symbol#CONSTANT_METHODREF_TAG}
+ * or {@link Symbol#CONSTANT_INTERFACE_METHODREF_TAG}.
+ * @param owner the internal name of a class.
+ * @param name a field or method name.
+ * @param descriptor a field or method descriptor.
+ * @return a new or already existing Symbol with the given value.
+ */
+ private Entry addConstantMemberReference(
+ final int tag, final String owner, final String name, final String descriptor) {
+ int hashCode = hash(tag, owner, name, descriptor);
+ Entry entry = get(hashCode);
+ while (entry != null) {
+ if (entry.tag == tag
+ && entry.hashCode == hashCode
+ && entry.owner.equals(owner)
+ && entry.name.equals(name)
+ && entry.value.equals(descriptor)) {
+ return entry;
+ }
+ entry = entry.next;
+ }
+ constantPool.put122(
+ tag, addConstantClass(owner).index, addConstantNameAndType(name, descriptor));
+ return put(new Entry(constantPoolCount++, tag, owner, name, descriptor, 0, hashCode));
+ }
+
+ /**
+ * Adds a new CONSTANT_Fieldref_info, CONSTANT_Methodref_info or CONSTANT_InterfaceMethodref_info
+ * to the constant pool of this symbol table.
+ *
+ * @param index the constant pool index of the new Symbol.
+ * @param tag one of {@link Symbol#CONSTANT_FIELDREF_TAG}, {@link Symbol#CONSTANT_METHODREF_TAG}
+ * or {@link Symbol#CONSTANT_INTERFACE_METHODREF_TAG}.
+ * @param owner the internal name of a class.
+ * @param name a field or method name.
+ * @param descriptor a field or method descriptor.
+ */
+ private void addConstantMemberReference(
+ final int index,
+ final int tag,
+ final String owner,
+ final String name,
+ final String descriptor) {
+ add(new Entry(index, tag, owner, name, descriptor, 0, hash(tag, owner, name, descriptor)));
+ }
+
+ /**
+ * Adds a CONSTANT_String_info to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param value a string.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantString(final String value) {
+ return addConstantUtf8Reference(Symbol.CONSTANT_STRING_TAG, value);
+ }
+
+ /**
+ * Adds a CONSTANT_Integer_info to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param value an int.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantInteger(final int value) {
+ return addConstantIntegerOrFloat(Symbol.CONSTANT_INTEGER_TAG, value);
+ }
+
+ /**
+ * Adds a CONSTANT_Float_info to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param value a float.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantFloat(final float value) {
+ return addConstantIntegerOrFloat(Symbol.CONSTANT_FLOAT_TAG, Float.floatToRawIntBits(value));
+ }
+
+ /**
+ * Adds a CONSTANT_Integer_info or CONSTANT_Float_info to the constant pool of this symbol table.
+ * Does nothing if the constant pool already contains a similar item.
+ *
+ * @param tag one of {@link Symbol#CONSTANT_INTEGER_TAG} or {@link Symbol#CONSTANT_FLOAT_TAG}.
+ * @param value an int or float.
+ * @return a constant pool constant with the given tag and primitive values.
+ */
+ private Symbol addConstantIntegerOrFloat(final int tag, final int value) {
+ int hashCode = hash(tag, value);
+ Entry entry = get(hashCode);
+ while (entry != null) {
+ if (entry.tag == tag && entry.hashCode == hashCode && entry.data == value) {
+ return entry;
+ }
+ entry = entry.next;
+ }
+ constantPool.putByte(tag).putInt(value);
+ return put(new Entry(constantPoolCount++, tag, value, hashCode));
+ }
+
+ /**
+ * Adds a new CONSTANT_Integer_info or CONSTANT_Float_info to the constant pool of this symbol
+ * table.
+ *
+ * @param index the constant pool index of the new Symbol.
+ * @param tag one of {@link Symbol#CONSTANT_INTEGER_TAG} or {@link Symbol#CONSTANT_FLOAT_TAG}.
+ * @param value an int or float.
+ */
+ private void addConstantIntegerOrFloat(final int index, final int tag, final int value) {
+ add(new Entry(index, tag, value, hash(tag, value)));
+ }
+
+ /**
+ * Adds a CONSTANT_Long_info to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param value a long.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantLong(final long value) {
+ return addConstantLongOrDouble(Symbol.CONSTANT_LONG_TAG, value);
+ }
+
+ /**
+ * Adds a CONSTANT_Double_info to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param value a double.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantDouble(final double value) {
+ return addConstantLongOrDouble(Symbol.CONSTANT_DOUBLE_TAG, Double.doubleToRawLongBits(value));
+ }
+
+ /**
+ * Adds a CONSTANT_Long_info or CONSTANT_Double_info to the constant pool of this symbol table.
+ * Does nothing if the constant pool already contains a similar item.
+ *
+ * @param tag one of {@link Symbol#CONSTANT_LONG_TAG} or {@link Symbol#CONSTANT_DOUBLE_TAG}.
+ * @param value a long or double.
+ * @return a constant pool constant with the given tag and primitive values.
+ */
+ private Symbol addConstantLongOrDouble(final int tag, final long value) {
+ int hashCode = hash(tag, value);
+ Entry entry = get(hashCode);
+ while (entry != null) {
+ if (entry.tag == tag && entry.hashCode == hashCode && entry.data == value) {
+ return entry;
+ }
+ entry = entry.next;
+ }
+ int index = constantPoolCount;
+ constantPool.putByte(tag).putLong(value);
+ constantPoolCount += 2;
+ return put(new Entry(index, tag, value, hashCode));
+ }
+
+ /**
+ * Adds a new CONSTANT_Long_info or CONSTANT_Double_info to the constant pool of this symbol
+ * table.
+ *
+ * @param index the constant pool index of the new Symbol.
+ * @param tag one of {@link Symbol#CONSTANT_LONG_TAG} or {@link Symbol#CONSTANT_DOUBLE_TAG}.
+ * @param value a long or double.
+ */
+ private void addConstantLongOrDouble(final int index, final int tag, final long value) {
+ add(new Entry(index, tag, value, hash(tag, value)));
+ }
+
+ /**
+ * Adds a CONSTANT_NameAndType_info to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param name a field or method name.
+ * @param descriptor a field or method descriptor.
+ * @return a new or already existing Symbol with the given value.
+ */
+ int addConstantNameAndType(final String name, final String descriptor) {
+ final int tag = Symbol.CONSTANT_NAME_AND_TYPE_TAG;
+ int hashCode = hash(tag, name, descriptor);
+ Entry entry = get(hashCode);
+ while (entry != null) {
+ if (entry.tag == tag
+ && entry.hashCode == hashCode
+ && entry.name.equals(name)
+ && entry.value.equals(descriptor)) {
+ return entry.index;
+ }
+ entry = entry.next;
+ }
+ constantPool.put122(tag, addConstantUtf8(name), addConstantUtf8(descriptor));
+ return put(new Entry(constantPoolCount++, tag, name, descriptor, hashCode)).index;
+ }
+
+ /**
+ * Adds a new CONSTANT_NameAndType_info to the constant pool of this symbol table.
+ *
+ * @param index the constant pool index of the new Symbol.
+ * @param name a field or method name.
+ * @param descriptor a field or method descriptor.
+ */
+ private void addConstantNameAndType(final int index, final String name, final String descriptor) {
+ final int tag = Symbol.CONSTANT_NAME_AND_TYPE_TAG;
+ add(new Entry(index, tag, name, descriptor, hash(tag, name, descriptor)));
+ }
+
+ /**
+ * Adds a CONSTANT_Utf8_info to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param value a string.
+ * @return a new or already existing Symbol with the given value.
+ */
+ int addConstantUtf8(final String value) {
+ int hashCode = hash(Symbol.CONSTANT_UTF8_TAG, value);
+ Entry entry = get(hashCode);
+ while (entry != null) {
+ if (entry.tag == Symbol.CONSTANT_UTF8_TAG
+ && entry.hashCode == hashCode
+ && entry.value.equals(value)) {
+ return entry.index;
+ }
+ entry = entry.next;
+ }
+ constantPool.putByte(Symbol.CONSTANT_UTF8_TAG).putUTF8(value);
+ return put(new Entry(constantPoolCount++, Symbol.CONSTANT_UTF8_TAG, value, hashCode)).index;
+ }
+
+ /**
+ * Adds a new CONSTANT_String_info to the constant pool of this symbol table.
+ *
+ * @param index the constant pool index of the new Symbol.
+ * @param value a string.
+ */
+ private void addConstantUtf8(final int index, final String value) {
+ add(new Entry(index, Symbol.CONSTANT_UTF8_TAG, value, hash(Symbol.CONSTANT_UTF8_TAG, value)));
+ }
+
+ /**
+ * Adds a CONSTANT_MethodHandle_info to the constant pool of this symbol table. Does nothing if
+ * the constant pool already contains a similar item.
+ *
+ * @param referenceKind one of {@link Opcodes#H_GETFIELD}, {@link Opcodes#H_GETSTATIC}, {@link
+ * Opcodes#H_PUTFIELD}, {@link Opcodes#H_PUTSTATIC}, {@link Opcodes#H_INVOKEVIRTUAL}, {@link
+ * Opcodes#H_INVOKESTATIC}, {@link Opcodes#H_INVOKESPECIAL}, {@link
+ * Opcodes#H_NEWINVOKESPECIAL} or {@link Opcodes#H_INVOKEINTERFACE}.
+ * @param owner the internal name of a class of interface.
+ * @param name a field or method name.
+ * @param descriptor a field or method descriptor.
+ * @param isInterface whether owner is an interface or not.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantMethodHandle(
+ final int referenceKind,
+ final String owner,
+ final String name,
+ final String descriptor,
+ final boolean isInterface) {
+ final int tag = Symbol.CONSTANT_METHOD_HANDLE_TAG;
+ // Note that we don't need to include isInterface in the hash computation, because it is
+ // redundant with owner (we can't have the same owner with different isInterface values).
+ int hashCode = hash(tag, owner, name, descriptor, referenceKind);
+ Entry entry = get(hashCode);
+ while (entry != null) {
+ if (entry.tag == tag
+ && entry.hashCode == hashCode
+ && entry.data == referenceKind
+ && entry.owner.equals(owner)
+ && entry.name.equals(name)
+ && entry.value.equals(descriptor)) {
+ return entry;
+ }
+ entry = entry.next;
+ }
+ if (referenceKind <= Opcodes.H_PUTSTATIC) {
+ constantPool.put112(tag, referenceKind, addConstantFieldref(owner, name, descriptor).index);
+ } else {
+ constantPool.put112(
+ tag, referenceKind, addConstantMethodref(owner, name, descriptor, isInterface).index);
+ }
+ return put(
+ new Entry(constantPoolCount++, tag, owner, name, descriptor, referenceKind, hashCode));
+ }
+
+ /**
+ * Adds a new CONSTANT_MethodHandle_info to the constant pool of this symbol table.
+ *
+ * @param index the constant pool index of the new Symbol.
+ * @param referenceKind one of {@link Opcodes#H_GETFIELD}, {@link Opcodes#H_GETSTATIC}, {@link
+ * Opcodes#H_PUTFIELD}, {@link Opcodes#H_PUTSTATIC}, {@link Opcodes#H_INVOKEVIRTUAL}, {@link
+ * Opcodes#H_INVOKESTATIC}, {@link Opcodes#H_INVOKESPECIAL}, {@link
+ * Opcodes#H_NEWINVOKESPECIAL} or {@link Opcodes#H_INVOKEINTERFACE}.
+ * @param owner the internal name of a class of interface.
+ * @param name a field or method name.
+ * @param descriptor a field or method descriptor.
+ */
+ private void addConstantMethodHandle(
+ final int index,
+ final int referenceKind,
+ final String owner,
+ final String name,
+ final String descriptor) {
+ final int tag = Symbol.CONSTANT_METHOD_HANDLE_TAG;
+ int hashCode = hash(tag, owner, name, descriptor, referenceKind);
+ add(new Entry(index, tag, owner, name, descriptor, referenceKind, hashCode));
+ }
+
+ /**
+ * Adds a CONSTANT_MethodType_info to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param methodDescriptor a method descriptor.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantMethodType(final String methodDescriptor) {
+ return addConstantUtf8Reference(Symbol.CONSTANT_METHOD_TYPE_TAG, methodDescriptor);
+ }
+
+ /**
+ * Adds a CONSTANT_Dynamic_info to the constant pool of this symbol table. Also adds the related
+ * bootstrap method to the BootstrapMethods of this symbol table. Does nothing if the constant
+ * pool already contains a similar item.
+ *
+ * @param name a method name.
+ * @param descriptor a field descriptor.
+ * @param bootstrapMethodHandle a bootstrap method handle.
+ * @param bootstrapMethodArguments the bootstrap method arguments.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantDynamic(
+ final String name,
+ final String descriptor,
+ final Handle bootstrapMethodHandle,
+ final Object... bootstrapMethodArguments) {
+ Symbol bootstrapMethod = addBootstrapMethod(bootstrapMethodHandle, bootstrapMethodArguments);
+ return addConstantDynamicOrInvokeDynamicReference(
+ Symbol.CONSTANT_DYNAMIC_TAG, name, descriptor, bootstrapMethod.index);
+ }
+
+ /**
+ * Adds a CONSTANT_InvokeDynamic_info to the constant pool of this symbol table. Also adds the
+ * related bootstrap method to the BootstrapMethods of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param name a method name.
+ * @param descriptor a method descriptor.
+ * @param bootstrapMethodHandle a bootstrap method handle.
+ * @param bootstrapMethodArguments the bootstrap method arguments.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantInvokeDynamic(
+ final String name,
+ final String descriptor,
+ final Handle bootstrapMethodHandle,
+ final Object... bootstrapMethodArguments) {
+ Symbol bootstrapMethod = addBootstrapMethod(bootstrapMethodHandle, bootstrapMethodArguments);
+ return addConstantDynamicOrInvokeDynamicReference(
+ Symbol.CONSTANT_INVOKE_DYNAMIC_TAG, name, descriptor, bootstrapMethod.index);
+ }
+
+ /**
+ * Adds a CONSTANT_Dynamic or a CONSTANT_InvokeDynamic_info to the constant pool of this symbol
+ * table. Does nothing if the constant pool already contains a similar item.
+ *
+ * @param tag one of {@link Symbol#CONSTANT_DYNAMIC_TAG} or {@link
+ * Symbol#CONSTANT_INVOKE_DYNAMIC_TAG}.
+ * @param name a method name.
+ * @param descriptor a field descriptor for CONSTANT_DYNAMIC_TAG) or a method descriptor for
+ * CONSTANT_INVOKE_DYNAMIC_TAG.
+ * @param bootstrapMethodIndex the index of a bootstrap method in the BootstrapMethods attribute.
+ * @return a new or already existing Symbol with the given value.
+ */
+ private Symbol addConstantDynamicOrInvokeDynamicReference(
+ final int tag, final String name, final String descriptor, final int bootstrapMethodIndex) {
+ int hashCode = hash(tag, name, descriptor, bootstrapMethodIndex);
+ Entry entry = get(hashCode);
+ while (entry != null) {
+ if (entry.tag == tag
+ && entry.hashCode == hashCode
+ && entry.data == bootstrapMethodIndex
+ && entry.name.equals(name)
+ && entry.value.equals(descriptor)) {
+ return entry;
+ }
+ entry = entry.next;
+ }
+ constantPool.put122(tag, bootstrapMethodIndex, addConstantNameAndType(name, descriptor));
+ return put(
+ new Entry(
+ constantPoolCount++, tag, null, name, descriptor, bootstrapMethodIndex, hashCode));
+ }
+
+ /**
+ * Adds a new CONSTANT_Dynamic_info or CONSTANT_InvokeDynamic_info to the constant pool of this
+ * symbol table.
+ *
+ * @param tag one of {@link Symbol#CONSTANT_DYNAMIC_TAG} or {@link
+ * Symbol#CONSTANT_INVOKE_DYNAMIC_TAG}.
+ * @param index the constant pool index of the new Symbol.
+ * @param name a method name.
+ * @param descriptor a field descriptor for CONSTANT_DYNAMIC_TAG or a method descriptor for
+ * CONSTANT_INVOKE_DYNAMIC_TAG.
+ * @param bootstrapMethodIndex the index of a bootstrap method in the BootstrapMethods attribute.
+ */
+ private void addConstantDynamicOrInvokeDynamicReference(
+ final int tag,
+ final int index,
+ final String name,
+ final String descriptor,
+ final int bootstrapMethodIndex) {
+ int hashCode = hash(tag, name, descriptor, bootstrapMethodIndex);
+ add(new Entry(index, tag, null, name, descriptor, bootstrapMethodIndex, hashCode));
+ }
+
+ /**
+ * Adds a CONSTANT_Module_info to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param moduleName a fully qualified name (using dots) of a module.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantModule(final String moduleName) {
+ return addConstantUtf8Reference(Symbol.CONSTANT_MODULE_TAG, moduleName);
+ }
+
+ /**
+ * Adds a CONSTANT_Package_info to the constant pool of this symbol table. Does nothing if the
+ * constant pool already contains a similar item.
+ *
+ * @param packageName the internal name of a package.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addConstantPackage(final String packageName) {
+ return addConstantUtf8Reference(Symbol.CONSTANT_PACKAGE_TAG, packageName);
+ }
+
+ /**
+ * Adds a CONSTANT_Class_info, CONSTANT_String_info, CONSTANT_MethodType_info,
+ * CONSTANT_Module_info or CONSTANT_Package_info to the constant pool of this symbol table. Does
+ * nothing if the constant pool already contains a similar item.
+ *
+ * @param tag one of {@link Symbol#CONSTANT_CLASS_TAG}, {@link Symbol#CONSTANT_STRING_TAG}, {@link
+ * Symbol#CONSTANT_METHOD_TYPE_TAG}, {@link Symbol#CONSTANT_MODULE_TAG} or {@link
+ * Symbol#CONSTANT_PACKAGE_TAG}.
+ * @param value an internal class name, an arbitrary string, a method descriptor, a module or a
+ * package name, depending on tag.
+ * @return a new or already existing Symbol with the given value.
+ */
+ private Symbol addConstantUtf8Reference(final int tag, final String value) {
+ int hashCode = hash(tag, value);
+ Entry entry = get(hashCode);
+ while (entry != null) {
+ if (entry.tag == tag && entry.hashCode == hashCode && entry.value.equals(value)) {
+ return entry;
+ }
+ entry = entry.next;
+ }
+ constantPool.put12(tag, addConstantUtf8(value));
+ return put(new Entry(constantPoolCount++, tag, value, hashCode));
+ }
+
+ /**
+ * Adds a new CONSTANT_Class_info, CONSTANT_String_info, CONSTANT_MethodType_info,
+ * CONSTANT_Module_info or CONSTANT_Package_info to the constant pool of this symbol table.
+ *
+ * @param index the constant pool index of the new Symbol.
+ * @param tag one of {@link Symbol#CONSTANT_CLASS_TAG}, {@link Symbol#CONSTANT_STRING_TAG}, {@link
+ * Symbol#CONSTANT_METHOD_TYPE_TAG}, {@link Symbol#CONSTANT_MODULE_TAG} or {@link
+ * Symbol#CONSTANT_PACKAGE_TAG}.
+ * @param value an internal class name, an arbitrary string, a method descriptor, a module or a
+ * package name, depending on tag.
+ */
+ private void addConstantUtf8Reference(final int index, final int tag, final String value) {
+ add(new Entry(index, tag, value, hash(tag, value)));
+ }
+
+ // -----------------------------------------------------------------------------------------------
+ // Bootstrap method entries management.
+ // -----------------------------------------------------------------------------------------------
+
+ /**
+ * Adds a bootstrap method to the BootstrapMethods attribute of this symbol table. Does nothing if
+ * the BootstrapMethods already contains a similar bootstrap method.
+ *
+ * @param bootstrapMethodHandle a bootstrap method handle.
+ * @param bootstrapMethodArguments the bootstrap method arguments.
+ * @return a new or already existing Symbol with the given value.
+ */
+ Symbol addBootstrapMethod(
+ final Handle bootstrapMethodHandle, final Object... bootstrapMethodArguments) {
+ ByteVector bootstrapMethodsAttribute = bootstrapMethods;
+ if (bootstrapMethodsAttribute == null) {
+ bootstrapMethodsAttribute = bootstrapMethods = new ByteVector();
+ }
+
+ // The bootstrap method arguments can be Constant_Dynamic values, which reference other
+ // bootstrap methods. We must therefore add the bootstrap method arguments to the constant pool
+ // and BootstrapMethods attribute first, so that the BootstrapMethods attribute is not modified
+ // while adding the given bootstrap method to it, in the rest of this method.
+ for (Object bootstrapMethodArgument : bootstrapMethodArguments) {
+ addConstant(bootstrapMethodArgument);
+ }
+
+ // Write the bootstrap method in the BootstrapMethods table. This is necessary to be able to
+ // compare it with existing ones, and will be reverted below if there is already a similar
+ // bootstrap method.
+ int bootstrapMethodOffset = bootstrapMethodsAttribute.length;
+ bootstrapMethodsAttribute.putShort(
+ addConstantMethodHandle(
+ bootstrapMethodHandle.getTag(),
+ bootstrapMethodHandle.getOwner(),
+ bootstrapMethodHandle.getName(),
+ bootstrapMethodHandle.getDesc(),
+ bootstrapMethodHandle.isInterface())
+ .index);
+ int numBootstrapArguments = bootstrapMethodArguments.length;
+ bootstrapMethodsAttribute.putShort(numBootstrapArguments);
+ for (Object bootstrapMethodArgument : bootstrapMethodArguments) {
+ bootstrapMethodsAttribute.putShort(addConstant(bootstrapMethodArgument).index);
+ }
+
+ // Compute the length and the hash code of the bootstrap method.
+ int bootstrapMethodlength = bootstrapMethodsAttribute.length - bootstrapMethodOffset;
+ int hashCode = bootstrapMethodHandle.hashCode();
+ for (Object bootstrapMethodArgument : bootstrapMethodArguments) {
+ hashCode ^= bootstrapMethodArgument.hashCode();
+ }
+ hashCode &= 0x7FFFFFFF;
+
+ // Add the bootstrap method to the symbol table or revert the above changes.
+ return addBootstrapMethod(bootstrapMethodOffset, bootstrapMethodlength, hashCode);
+ }
+
+ /**
+ * Adds a bootstrap method to the BootstrapMethods attribute of this symbol table. Does nothing if
+ * the BootstrapMethods already contains a similar bootstrap method (more precisely, reverts the
+ * content of {@link #bootstrapMethods} to remove the last, duplicate bootstrap method).
+ *
+ * @param offset the offset of the last bootstrap method in {@link #bootstrapMethods}, in bytes.
+ * @param length the length of this bootstrap method in {@link #bootstrapMethods}, in bytes.
+ * @param hashCode the hash code of this bootstrap method.
+ * @return a new or already existing Symbol with the given value.
+ */
+ private Symbol addBootstrapMethod(final int offset, final int length, final int hashCode) {
+ final byte[] bootstrapMethodsData = bootstrapMethods.data;
+ Entry entry = get(hashCode);
+ while (entry != null) {
+ if (entry.tag == Symbol.BOOTSTRAP_METHOD_TAG && entry.hashCode == hashCode) {
+ int otherOffset = (int) entry.data;
+ boolean isSameBootstrapMethod = true;
+ for (int i = 0; i < length; ++i) {
+ if (bootstrapMethodsData[offset + i] != bootstrapMethodsData[otherOffset + i]) {
+ isSameBootstrapMethod = false;
+ break;
+ }
+ }
+ if (isSameBootstrapMethod) {
+ bootstrapMethods.length = offset; // Revert to old position.
+ return entry;
+ }
+ }
+ entry = entry.next;
+ }
+ return put(new Entry(bootstrapMethodCount++, Symbol.BOOTSTRAP_METHOD_TAG, offset, hashCode));
+ }
+
+ // -----------------------------------------------------------------------------------------------
+ // Type table entries management.
+ // -----------------------------------------------------------------------------------------------
+
+ /**
+ * Returns the type table element whose index is given.
+ *
+ * @param typeIndex a type table index.
+ * @return the type table element whose index is given.
+ */
+ Symbol getType(final int typeIndex) {
+ return typeTable[typeIndex];
+ }
+
+ /**
+ * Adds a type in the type table of this symbol table. Does nothing if the type table already
+ * contains a similar type.
+ *
+ * @param value an internal class name.
+ * @return the index of a new or already existing type Symbol with the given value.
+ */
+ int addType(final String value) {
+ int hashCode = hash(Symbol.TYPE_TAG, value);
+ Entry entry = get(hashCode);
+ while (entry != null) {
+ if (entry.tag == Symbol.TYPE_TAG && entry.hashCode == hashCode && entry.value.equals(value)) {
+ return entry.index;
+ }
+ entry = entry.next;
+ }
+ return addTypeInternal(new Entry(typeCount, Symbol.TYPE_TAG, value, hashCode));
+ }
+
+ /**
+ * Adds an {@link Frame#ITEM_UNINITIALIZED} type in the type table of this symbol table. Does
+ * nothing if the type table already contains a similar type.
+ *
+ * @param value an internal class name.
+ * @param bytecodeOffset the bytecode offset of the NEW instruction that created this {@link
+ * Frame#ITEM_UNINITIALIZED} type value.
+ * @return the index of a new or already existing type Symbol with the given value.
+ */
+ int addUninitializedType(final String value, final int bytecodeOffset) {
+ int hashCode = hash(Symbol.UNINITIALIZED_TYPE_TAG, value, bytecodeOffset);
+ Entry entry = get(hashCode);
+ while (entry != null) {
+ if (entry.tag == Symbol.UNINITIALIZED_TYPE_TAG
+ && entry.hashCode == hashCode
+ && entry.data == bytecodeOffset
+ && entry.value.equals(value)) {
+ return entry.index;
+ }
+ entry = entry.next;
+ }
+ return addTypeInternal(
+ new Entry(typeCount, Symbol.UNINITIALIZED_TYPE_TAG, value, bytecodeOffset, hashCode));
+ }
+
+ /**
+ * Adds a merged type in the type table of this symbol table. Does nothing if the type table
+ * already contains a similar type.
+ *
+ * @param typeTableIndex1 a {@link Symbol#TYPE_TAG} type, specified by its index in the type
+ * table.
+ * @param typeTableIndex2 another {@link Symbol#TYPE_TAG} type, specified by its index in the type
+ * table.
+ * @return the index of a new or already existing {@link Symbol#TYPE_TAG} type Symbol,
+ * corresponding to the common super class of the given types.
+ */
+ int addMergedType(final int typeTableIndex1, final int typeTableIndex2) {
+ // TODO sort the arguments? The merge result should be independent of their order.
+ long data = typeTableIndex1 | (((long) typeTableIndex2) << 32);
+ int hashCode = hash(Symbol.MERGED_TYPE_TAG, typeTableIndex1 + typeTableIndex2);
+ Entry entry = get(hashCode);
+ while (entry != null) {
+ if (entry.tag == Symbol.MERGED_TYPE_TAG && entry.hashCode == hashCode && entry.data == data) {
+ return entry.info;
+ }
+ entry = entry.next;
+ }
+ String type1 = typeTable[typeTableIndex1].value;
+ String type2 = typeTable[typeTableIndex2].value;
+ int commonSuperTypeIndex = addType(classWriter.getCommonSuperClass(type1, type2));
+ put(new Entry(typeCount, Symbol.MERGED_TYPE_TAG, data, hashCode)).info = commonSuperTypeIndex;
+ return commonSuperTypeIndex;
+ }
+
+ /**
+ * Adds the given type Symbol to {@link #typeTable}.
+ *
+ * @param entry a {@link Symbol#TYPE_TAG} or {@link Symbol#UNINITIALIZED_TYPE_TAG} type symbol.
+ * The index of this Symbol must be equal to the current value of {@link #typeCount}.
+ * @return the index in {@link #typeTable} where the given type was added, which is also equal to
+ * entry's index by hypothesis.
+ */
+ private int addTypeInternal(final Entry entry) {
+ if (typeTable == null) {
+ typeTable = new Entry[16];
+ }
+ if (typeCount == typeTable.length) {
+ Entry[] newTypeTable = new Entry[2 * typeTable.length];
+ System.arraycopy(typeTable, 0, newTypeTable, 0, typeTable.length);
+ typeTable = newTypeTable;
+ }
+ typeTable[typeCount++] = entry;
+ return put(entry).index;
+ }
+
+ // -----------------------------------------------------------------------------------------------
+ // Static helper methods to compute hash codes.
+ // -----------------------------------------------------------------------------------------------
+
+ private static int hash(final int tag, final int value) {
+ return 0x7FFFFFFF & (tag + value);
+ }
+
+ private static int hash(final int tag, final long value) {
+ return 0x7FFFFFFF & (tag + (int) value + (int) (value >>> 32));
+ }
+
+ private static int hash(final int tag, final String value) {
+ return 0x7FFFFFFF & (tag + value.hashCode());
+ }
+
+ private static int hash(final int tag, final String value1, final int value2) {
+ return 0x7FFFFFFF & (tag + value1.hashCode() + value2);
+ }
+
+ private static int hash(final int tag, final String value1, final String value2) {
+ return 0x7FFFFFFF & (tag + value1.hashCode() * value2.hashCode());
+ }
+
+ private static int hash(
+ final int tag, final String value1, final String value2, final int value3) {
+ return 0x7FFFFFFF & (tag + value1.hashCode() * value2.hashCode() * (value3 + 1));
+ }
+
+ private static int hash(
+ final int tag, final String value1, final String value2, final String value3) {
+ return 0x7FFFFFFF & (tag + value1.hashCode() * value2.hashCode() * value3.hashCode());
+ }
+
+ private static int hash(
+ final int tag,
+ final String value1,
+ final String value2,
+ final String value3,
+ final int value4) {
+ return 0x7FFFFFFF & (tag + value1.hashCode() * value2.hashCode() * value3.hashCode() * value4);
+ }
+
+ /**
+ * An entry of a SymbolTable. This concrete and private subclass of {@link Symbol} adds two fields
+ * which are only used inside SymbolTable, to implement hash sets of symbols (in order to avoid
+ * duplicate symbols). See {@link #entries}.
+ *
+ * @author Eric Bruneton
+ */
+ private static class Entry extends Symbol {
+
+ /** The hash code of this entry. */
+ final int hashCode;
+
+ /**
+ * Another entry (and so on recursively) having the same hash code (modulo the size of {@link
+ * #entries}) as this one.
+ */
+ Entry next;
+
+ Entry(
+ final int index,
+ final int tag,
+ final String owner,
+ final String name,
+ final String value,
+ final long data,
+ final int hashCode) {
+ super(index, tag, owner, name, value, data);
+ this.hashCode = hashCode;
+ }
+
+ Entry(final int index, final int tag, final String value, final int hashCode) {
+ super(index, tag, /* owner = */ null, /* name = */ null, value, /* data = */ 0);
+ this.hashCode = hashCode;
+ }
+
+ Entry(final int index, final int tag, final String value, final long data, final int hashCode) {
+ super(index, tag, /* owner = */ null, /* name = */ null, value, data);
+ this.hashCode = hashCode;
+ }
+
+ Entry(
+ final int index, final int tag, final String name, final String value, final int hashCode) {
+ super(index, tag, /* owner = */ null, name, value, /* data = */ 0);
+ this.hashCode = hashCode;
+ }
+
+ Entry(final int index, final int tag, final long data, final int hashCode) {
+ super(index, tag, /* owner = */ null, /* name = */ null, /* value = */ null, data);
+ this.hashCode = hashCode;
+ }
+ }
+}