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Posted to commits@commons.apache.org by ni...@apache.org on 2011/01/08 15:09:48 UTC

svn commit: r1056709 - in /commons/proper/lang/branches/LANG_2_X/src: main/java/org/apache/commons/lang/ObjectUtils.java main/java/org/apache/commons/lang/exception/CloneFailedException.java test/java/org/apache/commons/lang/ObjectUtilsTest.java

Author: niallp
Date: Sat Jan  8 14:09:48 2011
New Revision: 1056709

URL: http://svn.apache.org/viewvc?rev=1056709&view=rev
Log:
Port LANG-576 to LANG 2.x Branch - Add methods for cloneables to ObjectUtils

Added:
    commons/proper/lang/branches/LANG_2_X/src/main/java/org/apache/commons/lang/exception/CloneFailedException.java   (with props)
Modified:
    commons/proper/lang/branches/LANG_2_X/src/main/java/org/apache/commons/lang/ObjectUtils.java
    commons/proper/lang/branches/LANG_2_X/src/test/java/org/apache/commons/lang/ObjectUtilsTest.java

Modified: commons/proper/lang/branches/LANG_2_X/src/main/java/org/apache/commons/lang/ObjectUtils.java
URL: http://svn.apache.org/viewvc/commons/proper/lang/branches/LANG_2_X/src/main/java/org/apache/commons/lang/ObjectUtils.java?rev=1056709&r1=1056708&r2=1056709&view=diff
==============================================================================
--- commons/proper/lang/branches/LANG_2_X/src/main/java/org/apache/commons/lang/ObjectUtils.java (original)
+++ commons/proper/lang/branches/LANG_2_X/src/main/java/org/apache/commons/lang/ObjectUtils.java Sat Jan  8 14:09:48 2011
@@ -17,6 +17,11 @@
 package org.apache.commons.lang;
 
 import java.io.Serializable;
+import java.lang.reflect.Array;
+import java.lang.reflect.InvocationTargetException;
+
+import org.apache.commons.lang.exception.CloneFailedException;
+import org.apache.commons.lang.reflect.MethodUtils;
 
 /**
  * <p>Operations on <code>Object</code>.</p>
@@ -307,6 +312,67 @@ public class ObjectUtils {
             return c1 != null ? c1 : c2;
         }
     }
+    
+    /**
+     * Clone an object.
+     * 
+     * @param o the object to clone
+     * @return the clone if the object implements {@link Cloneable} otherwise <code>null</code>
+     * @throws CloneFailedException if the object is cloneable and the clone operation fails
+     * @since 2.6
+     */
+    public static Object clone(final Object o) {
+        if (o instanceof Cloneable) {
+            final Object result;
+            if (o.getClass().isArray()) {
+                final Class componentType = o.getClass().getComponentType();
+                if (!componentType.isPrimitive()) {
+                    result = ((Object[])o).clone();
+                } else {
+                    int length = Array.getLength(o);
+                    result = Array.newInstance(componentType, length);
+                    while (length-- > 0) {
+                        Array.set(result, length, Array.get(o, length));
+                    }
+                }
+            } else {
+                try {
+                    result = MethodUtils.invokeMethod(o, "clone", null);
+                } catch (final NoSuchMethodException e) {
+                    throw new CloneFailedException("Cloneable type "
+                        + o.getClass().getName()
+                        + " has no clone method: " + e);
+                } catch (final IllegalAccessException e) {
+                    throw new CloneFailedException("Cannot clone Cloneable type "
+                        + o.getClass().getName() + ": " + e);
+                } catch (final InvocationTargetException e) {
+                    throw new CloneFailedException("Exception cloning Cloneable type "
+                        + o.getClass().getName() + ": " + e.getTargetException());
+                }
+            }
+            return result;
+        }
+
+        return null;
+    }
+
+    /**
+     * Clone an object if possible. This method is similar to {@link #clone(Object)}, but will
+     * return the provided instance as the return value instead of <code>null</code> if the instance
+     * is not cloneable. This is more convenient if the caller uses different
+     * implementations (e.g. of a service) and some of the implementations do not allow concurrent
+     * processing or have state. In such cases the implementation can simply provide a proper
+     * clone implementation and the caller's code does not have to change.
+     * 
+     * @param o the object to clone
+     * @return the clone if the object implements {@link Cloneable} otherwise the object itself
+     * @throws CloneFailedException if the object is cloneable and the clone operation fails
+     * @since 2.6
+     */
+    public static Object cloneIfPossible(final Object o) {
+        final Object clone = clone(o);
+        return clone == null ? o : clone;
+    }
 
     // Null
     //-----------------------------------------------------------------------

Added: commons/proper/lang/branches/LANG_2_X/src/main/java/org/apache/commons/lang/exception/CloneFailedException.java
URL: http://svn.apache.org/viewvc/commons/proper/lang/branches/LANG_2_X/src/main/java/org/apache/commons/lang/exception/CloneFailedException.java?rev=1056709&view=auto
==============================================================================
--- commons/proper/lang/branches/LANG_2_X/src/main/java/org/apache/commons/lang/exception/CloneFailedException.java (added)
+++ commons/proper/lang/branches/LANG_2_X/src/main/java/org/apache/commons/lang/exception/CloneFailedException.java Sat Jan  8 14:09:48 2011
@@ -0,0 +1,42 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.lang.exception;
+
+/**
+ * Exception thrown when a clone cannot be created. In contrast to
+ * {@link CloneNotSupportedException} this is a {@link RuntimeException}.
+ * 
+ * @author Apache Software Foundation
+ * @since 2.6
+ */
+public class CloneFailedException extends RuntimeException {
+    // ~ Static fields/initializers ---------------------------------------------
+
+    private static final long serialVersionUID = 20091223L;
+
+    // ~ Constructors -----------------------------------------------------------
+
+    /**
+     * Constructs a CloneFailedException.
+     * 
+     * @param message description of the exception
+     * @since upcoming
+     */
+    public CloneFailedException(final String message) {
+        super(message);
+    }
+}

Propchange: commons/proper/lang/branches/LANG_2_X/src/main/java/org/apache/commons/lang/exception/CloneFailedException.java
------------------------------------------------------------------------------
    svn:eol-style = native

Propchange: commons/proper/lang/branches/LANG_2_X/src/main/java/org/apache/commons/lang/exception/CloneFailedException.java
------------------------------------------------------------------------------
    svn:keywords = Date Author Id Revision HeadURL

Modified: commons/proper/lang/branches/LANG_2_X/src/test/java/org/apache/commons/lang/ObjectUtilsTest.java
URL: http://svn.apache.org/viewvc/commons/proper/lang/branches/LANG_2_X/src/test/java/org/apache/commons/lang/ObjectUtilsTest.java?rev=1056709&r1=1056708&r2=1056709&view=diff
==============================================================================
--- commons/proper/lang/branches/LANG_2_X/src/test/java/org/apache/commons/lang/ObjectUtilsTest.java (original)
+++ commons/proper/lang/branches/LANG_2_X/src/test/java/org/apache/commons/lang/ObjectUtilsTest.java Sat Jan  8 14:09:48 2011
@@ -18,10 +18,14 @@ package org.apache.commons.lang;
 
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Modifier;
+import java.util.Arrays;
 import java.util.Calendar;
 
 import junit.framework.TestCase;
 
+import org.apache.commons.lang.exception.CloneFailedException;
+import org.apache.commons.lang.mutable.MutableObject;
+
 /**
  * Unit tests {@link org.apache.commons.lang.ObjectUtils}.
  *
@@ -204,4 +208,104 @@ public class ObjectUtilsTest extends Tes
         assertSame( minComparable, ObjectUtils.min( nonNullComparable1, minComparable ) );
         assertSame( minComparable, ObjectUtils.min( minComparable, nonNullComparable1 ) );
     }
+
+    /**
+     * Tests {@link ObjectUtils#clone(Object)} with a cloneable object.
+     */
+    public void testCloneOfCloneable() {
+        final CloneableString string = new CloneableString("apache");
+        final CloneableString stringClone = (CloneableString)ObjectUtils.clone(string);
+        assertEquals("apache", stringClone.getValue());
+    }
+
+    /**
+     * Tests {@link ObjectUtils#clone(Object)} with a not cloneable object.
+     */
+    public void testCloneOfNotCloneable() {
+        final String string = new String("apache");
+        assertNull(ObjectUtils.clone(string));
+    }
+
+    /**
+     * Tests {@link ObjectUtils#clone(Object)} with an uncloneable object.
+     */
+    public void testCloneOfUncloneable() {
+        final UncloneableString string = new UncloneableString("apache");
+        try {
+            ObjectUtils.clone(string);
+            fail("Thrown " + CloneFailedException.class.getName() + " expected");
+        } catch (final CloneFailedException e) {
+            //expected result
+        }
+    }
+
+    /**
+     * Tests {@link ObjectUtils#clone(Object)} with an object array.
+     */
+    public void testCloneOfStringArray() {
+        assertTrue(Arrays.equals(
+            new String[]{"string"}, (String[])ObjectUtils.clone(new String[]{"string"})));
+    }
+
+    /**
+     * Tests {@link ObjectUtils#clone(Object)} with an array of primitives.
+     */
+    public void testCloneOfPrimitiveArray() {
+        assertTrue(Arrays.equals(new int[]{1}, (int[])ObjectUtils.clone(new int[]{1})));
+    }
+
+    /**
+     * Tests {@link ObjectUtils#cloneIfPossible(Object)} with a cloneable object.
+     */
+    public void testPossibleCloneOfCloneable() {
+        final CloneableString string = new CloneableString("apache");
+        final CloneableString stringClone = (CloneableString)ObjectUtils.cloneIfPossible(string);
+        assertEquals("apache", stringClone.getValue());
+    }
+
+    /**
+     * Tests {@link ObjectUtils#cloneIfPossible(Object)} with a not cloneable object.
+     */
+    public void testPossibleCloneOfNotCloneable() {
+        final String string = new String("apache");
+        assertSame(string, ObjectUtils.cloneIfPossible(string));
+    }
+
+    /**
+     * Tests {@link ObjectUtils#cloneIfPossible(Object)} with an uncloneable object.
+     */
+    public void testPossibleCloneOfUncloneable() {
+        final UncloneableString string = new UncloneableString("apache");
+        try {
+            ObjectUtils.cloneIfPossible(string);
+            fail("Thrown " + CloneFailedException.class.getName() + " expected");
+        } catch (final CloneFailedException e) {
+            //expected result
+        }
+    }
+
+    /**
+     * String that is cloneable.
+     */
+    static final class CloneableString extends MutableObject implements Cloneable {
+        private static final long serialVersionUID = 1L;
+        CloneableString(final String s) {
+            super(s);
+        }
+
+        public Object clone() throws CloneNotSupportedException {
+            return (CloneableString)super.clone();
+        }
+    }
+
+    /**
+     * String that is not cloneable.
+     */
+    static final class UncloneableString extends MutableObject implements Cloneable {
+        private static final long serialVersionUID = 1L;
+        UncloneableString(final String s) {
+            super(s);
+        }
+    }
+
 }