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Posted to dev@tomcat.apache.org by co...@locus.apache.org on 2000/11/30 18:34:19 UTC

cvs commit: jakarta-tomcat/src/share/org/apache/tomcat/util/collections MultiMap.java SimpleHashtable.java package.html

costin      00/11/30 09:34:19

  Modified:    src/share/org/apache/tomcat/request SimpleMapper1.java
               src/share/org/apache/tomcat/util PrefixMapper.java
  Added:       src/share/org/apache/tomcat/util/collections MultiMap.java
                        SimpleHashtable.java package.html
  Removed:     src/share/org/apache/tomcat/util SimpleHashtable.java
  Log:
  Start refactoring of MimeHeaders, params and cookies.
  
  MultiMap is a subset of MimeHeaders ( same data representation, but only
  "generic" methods ) and will be the base of all 3 collections.
  ( we can add a hash and other optimizations, but after the refactoring is done)
  
  Also, moved SimpleHashtable to tomcat.util.collections - reduce the
  name polution in tomcat.util
  
  Revision  Changes    Path
  1.26      +1 -0      jakarta-tomcat/src/share/org/apache/tomcat/request/SimpleMapper1.java
  
  Index: SimpleMapper1.java
  ===================================================================
  RCS file: /home/cvs/jakarta-tomcat/src/share/org/apache/tomcat/request/SimpleMapper1.java,v
  retrieving revision 1.25
  retrieving revision 1.26
  diff -u -r1.25 -r1.26
  --- SimpleMapper1.java	2000/11/30 04:58:48	1.25
  +++ SimpleMapper1.java	2000/11/30 17:34:12	1.26
  @@ -63,6 +63,7 @@
   import org.apache.tomcat.core.*;
   import org.apache.tomcat.helper.*;
   import org.apache.tomcat.util.*;
  +import org.apache.tomcat.util.collections.*;
   import java.util.*;
   
   /**
  
  
  
  1.5       +5 -3      jakarta-tomcat/src/share/org/apache/tomcat/util/PrefixMapper.java
  
  Index: PrefixMapper.java
  ===================================================================
  RCS file: /home/cvs/jakarta-tomcat/src/share/org/apache/tomcat/util/PrefixMapper.java,v
  retrieving revision 1.4
  retrieving revision 1.5
  diff -u -r1.4 -r1.5
  --- PrefixMapper.java	2000/11/30 04:58:57	1.4
  +++ PrefixMapper.java	2000/11/30 17:34:12	1.5
  @@ -1,7 +1,7 @@
   /*
  - * $Header: /home/cvs/jakarta-tomcat/src/share/org/apache/tomcat/util/PrefixMapper.java,v 1.4 2000/11/30 04:58:57 costin Exp $
  - * $Revision: 1.4 $
  - * $Date: 2000/11/30 04:58:57 $
  + * $Header: /home/cvs/jakarta-tomcat/src/share/org/apache/tomcat/util/PrefixMapper.java,v 1.5 2000/11/30 17:34:12 costin Exp $
  + * $Revision: 1.5 $
  + * $Date: 2000/11/30 17:34:12 $
    *
    * ====================================================================
    *
  @@ -63,6 +63,8 @@
   
   
   package org.apache.tomcat.util;
  +
  +import org.apache.tomcat.util.collections.*;
   
   import java.net.URL;
   import java.io.File;
  
  
  
  1.1                  jakarta-tomcat/src/share/org/apache/tomcat/util/collections/MultiMap.java
  
  Index: MultiMap.java
  ===================================================================
  /*
   * ====================================================================
   *
   * The Apache Software License, Version 1.1
   *
   * Copyright (c) 1999 The Apache Software Foundation.  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. The end-user documentation included with the redistribution, if
   *    any, must include the following acknowlegement:  
   *       "This product includes software developed by the 
   *        Apache Software Foundation (http://www.apache.org/)."
   *    Alternately, this acknowlegement may appear in the software itself,
   *    if and wherever such third-party acknowlegements normally appear.
   *
   * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
   *    Foundation" must not be used to endorse or promote products derived
   *    from this software without prior written permission. For written 
   *    permission, please contact apache@apache.org.
   *
   * 5. Products derived from this software may not be called "Apache"
   *    nor may "Apache" appear in their names without prior written
   *    permission of the Apache Group.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 APACHE SOFTWARE FOUNDATION OR
   * ITS 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.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   *
   * [Additional notices, if required by prior licensing conditions]
   *
   */ 
  
  package org.apache.tomcat.util.collections;
  
  import org.apache.tomcat.util.MessageBytes;
  import java.io.*;
  import java.util.*;
  import java.text.*;
  
  // Originally MimeHeaders
  
  /**
   * An efficient representation for certain type of map. The keys 
   * can have a single or multi values, but most of the time there are
   * single values.
   *
   * The data is of "MessageBytes" type, meaning bytes[] that can be
   * converted to Strings ( if needed, and encoding is lazy-binded ).
   *
   * This is a base class for MimeHeaders, Parameters and Cookies.
   *
   * Data structures: each field is a single-valued key/value.
   * The fields are allocated when needed, and are recycled.
   * The current implementation does linear search, in future we'll
   * also use the hashkey.
   * 
   * @author dac@eng.sun.com
   * @author James Todd [gonzo@eng.sun.com]
   * @author Costin Manolache
   */
  public class MultiMap {
  
      protected Field[] fields;
      // fields in use
      protected int count;
  
      /**
       * 
       */
      public MultiMap(int initial_size) {
  	fields=new Field[initial_size];
      }
  
      /**
       * Clears all header fields.
       */
      public void recycle() {
  	for (int i = 0; i < count; i++) {
  	    fields[i].recycle();
  	}
  	count = 0;
      }
  
      // -------------------- Idx access to headers ----------
      // This allows external iterators.
      
      /**
       * Returns the current number of header fields.
       */
      public int size() {
  	return count;
      }
  
      /**
       * Returns the Nth header name
       * This may be used to iterate through all header fields.
       *
       * An exception is thrown if the index is not valid ( <0 or >size )
       */
      public MessageBytes getName(int n) {
  	// n >= 0 && n < count ? headers[n].getName() : null
  	return fields[n].name;
      }
  
      /**
       * Returns the Nth header value
       * This may be used to iterate through all header fields.
       */
      public MessageBytes getValue(int n) {
  	return fields[n].value;
      }
  
      /** Find the index of a field with the given name.
       */
      public int find( String name, int starting ) {
  	// We can use a hash - but it's not clear how much
  	// benefit you can get - there is an  overhead 
  	// and the number of headers is small (4-5 ?)
  	// Another problem is that we'll pay the overhead
  	// of constructing the hashtable
  
  	// A custom search tree may be better
          for (int i = starting; i < count; i++) {
  	    if (fields[i].name.equals(name)) {
                  return i;
              }
          }
          return -1;
      }
  
      /** Find the index of a field with the given name.
       */
      public int findIgnoreCase( String name, int starting ) {
  	// We can use a hash - but it's not clear how much
  	// benefit you can get - there is an  overhead 
  	// and the number of headers is small (4-5 ?)
  	// Another problem is that we'll pay the overhead
  	// of constructing the hashtable
  
  	// A custom search tree may be better
          for (int i = starting; i < count; i++) {
  	    if (fields[i].name.equalsIgnoreCase(name)) {
                  return i;
              }
          }
          return -1;
      }
  
      /**
       * Removes the field at the specified position.  
       *
       * MultiMap will preserve the order of field add unless remove()
       * is called. This is not thread-safe, and will invalidate all
       * iterators. 
       *
       * This is not a frequent operation for Headers and Parameters -
       * there are better ways ( like adding a "isValid" field )
       */
      public void remove( int i ) {
  	// reset and swap with last header
  	Field mh = fields[i];
  	// reset the field
  	mh.recycle();
  	
  	fields[i] = fields[count - 1];
  	fields[count - 1] = mh;
  	count--;
      }
  
      /** Create a new, unitialized entry. 
       */
      public int addField() {
  	int len = fields.length;
  	int pos=count;
  	if (count >= len) {
  	    // expand header list array
  	    Field tmp[] = new Field[pos * 2];
  	    System.arraycopy(fields, 0, tmp, 0, len);
  	    fields = tmp;
  	}
  	if (fields[pos] == null) {
  	    fields[pos] = new Field();
  	}
  	count++;
  	return pos;
      }
  
      public MessageBytes get( String name) {
          for (int i = 0; i < count; i++) {
  	    if (fields[i].name.equals(name)) {
  		return fields[i].value;
  	    }
  	}
          return null;
      }
  
      public int findFirst( String name ) {
          for (int i = 0; i < count; i++) {
  	    if (fields[i].name.equals(name)) {
  		return i;
  	    }
  	}
          return -1;
      }
  
      public int findNext( int startPos ) {
  	int next= fields[startPos].nextPos;
  	if( next != Field.NEED_NEXT ) {
  	    return next;
  	}
  
  	// next==NEED_NEXT, we never searched for this header
  	MessageBytes name=fields[startPos].name;
          for (int i = startPos; i < count; i++) {
  	    if (fields[i].name.equals(name)) {
  		// cache the search result
  		fields[startPos].nextPos=i;
  		return i;
  	    }
  	}
  	fields[startPos].nextPos= Field.LAST;
          return -1;
      }
  
      // -------------------- Internal representation --------------------
      final class Field {
  	MessageBytes name;
  	MessageBytes value;
  
  	// Extra info for speed
  	
  	//  multiple fields with same name - a linked list will
  	// speed up multiple name enumerations and search.
  	static final int NEED_NEXT=-2;
  	static final int LAST=-1;
  	int nextPos;
  
  	// hashkey
  	int hash;
  	Field nextSameHash;
  
  	Field() {
  	    nextPos=NEED_NEXT;
  	}
  	
  	void recycle() {
  	    name.recycle();
  	    value.recycle();
  	    nextPos=NEED_NEXT;
  	}
      }
  }
  
  
  
  1.1                  jakarta-tomcat/src/share/org/apache/tomcat/util/collections/SimpleHashtable.java
  
  Index: SimpleHashtable.java
  ===================================================================
  /*
   * ====================================================================
   *
   * The Apache Software License, Version 1.1
   *
   * Copyright (c) 1999 The Apache Software Foundation.  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. The end-user documentation included with the redistribution, if
   *    any, must include the following acknowlegement:  
   *       "This product includes software developed by the 
   *        Apache Software Foundation (http://www.apache.org/)."
   *    Alternately, this acknowlegement may appear in the software itself,
   *    if and wherever such third-party acknowlegements normally appear.
   *
   * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
   *    Foundation" must not be used to endorse or promote products derived
   *    from this software without prior written permission. For written 
   *    permission, please contact apache@apache.org.
   *
   * 5. Products derived from this software may not be called "Apache"
   *    nor may "Apache" appear in their names without prior written
   *    permission of the Apache Group.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 APACHE SOFTWARE FOUNDATION OR
   * ITS 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.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   *
   * [Additional notices, if required by prior licensing conditions]
   *
   */ 
  
  package org.apache.tomcat.util.collections;
  
  import java.util.*;
  
  /* **************************************** Stolen from Crimson ******************** */
  /* From Crimson/Parser - in a perfect world we'll just have a common set of
     utilities, and all apache project will just use those.
  
  */
  
  // can't be replaced using a Java 2 "Collections" API
  // since this package must also run on JDK 1.1
  
  
  /**
   * This class implements a special purpose hashtable.  It works like a
   * normal <code>java.util.Hashtable</code> except that: <OL>
   *
   *	<LI> Keys to "get" are strings which are known to be interned,
   *	so that "==" is used instead of "String.equals".  (Interning
   *	could be document-relative instead of global.)
   *
   *	<LI> It's not synchronized, since it's to be used only by
   *	one thread at a time.
   *
   *	<LI> The keys () enumerator allocates no memory, with live
   *	updates to the data disallowed.
   *
   *	<LI> It's got fewer bells and whistles:  fixed threshold and
   *	load factor, no JDK 1.2 collection support, only keys can be
   *	enumerated, things can't be removed, simpler inheritance; more.
   *
   *	</OL>
   *
   * <P> The overall result is that it's less expensive to use these in
   * performance-critical locations, in terms both of CPU and memory,
   * than <code>java.util.Hashtable</code> instances.  In this package
   * it makes a significant difference when normalizing attributes,
   * which is done for each start-element construct.
   *
   * @version $Revision: 1.1 $
   */
  public final class SimpleHashtable implements Enumeration
  {
      // entries ...
      private Entry		table[];
  
      // currently enumerated key
      private Entry		current = null;
      private int			currentBucket = 0;
  
      private int			count;
      private int			threshold;
  
      private static final float	loadFactor = 0.75f;
  
  
      /**
       * Constructs a new, empty hashtable with the specified initial 
       * capacity.
       *
       * @param      initialCapacity   the initial capacity of the hashtable.
       */
      public SimpleHashtable(int initialCapacity) {
  	if (initialCapacity < 0)
  	    throw new IllegalArgumentException("Illegal Capacity: "+
                                                 initialCapacity);
          if (initialCapacity==0)
              initialCapacity = 1;
  	table = new Entry[initialCapacity];
  	threshold = (int)(initialCapacity * loadFactor);
      }
  
      /**
       * Constructs a new, empty hashtable with a default capacity.
       */
      public SimpleHashtable() {
  	this(11);
      }
  
      /**
       */
      public void clear ()
      {
  	count = 0;
  	currentBucket = 0;
  	current = null;
  	for (int i = 0; i < table.length; i++)
  	    table [i] = null;
      }
  
      /**
       * Returns the number of keys in this hashtable.
       *
       * @return  the number of keys in this hashtable.
       */
      public int size() {
  	return count;
      }
  
      /**
       * Returns an enumeration of the keys in this hashtable.
       *
       * @return  an enumeration of the keys in this hashtable.
       * @see     Enumeration
       */
      public Enumeration keys() {
  	currentBucket = 0;
  	current = null;
  	return this;
      }
  
      /**
       * Used to view this as an enumeration; returns true if there
       * are more keys to be enumerated.
       */
      public boolean hasMoreElements ()
      {
  	if (current != null)
  	    return true;
  	while (currentBucket < table.length) {
  	    current = table [currentBucket++];
  	    if (current != null)
  		return true;
  	}
  	return false;
      }
  
      /**
       * Used to view this as an enumeration; returns the next key
       * in the enumeration.
       */
      public Object nextElement ()
      {
  	Object retval;
  
  	if (current == null)
  	    throw new IllegalStateException ();
  	retval = current.key;
  	current = current.next;
  	return retval;
      }
  
  
      /**
       * Returns the value to which the specified key is mapped in this hashtable.
       */
      public Object getInterned (String key) {
  	Entry tab[] = table;
  	int hash = key.hashCode();
  	int index = (hash & 0x7FFFFFFF) % tab.length;
  	for (Entry e = tab[index] ; e != null ; e = e.next) {
  	    if ((e.hash == hash) && (e.key == key))
  		return e.value;
  	}
  	return null;
      }
  
      /**
       * Returns the value to which the specified key is mapped in this
       * hashtable ... the key isn't necessarily interned, though.
       */
      public Object get(String key) {
  	Entry tab[] = table;
  	int hash = key.hashCode();
  	int index = (hash & 0x7FFFFFFF) % tab.length;
  	for (Entry e = tab[index] ; e != null ; e = e.next) {
  	    if ((e.hash == hash) && e.key.equals(key))
  		return e.value;
  	}
  	return null;
      }
  
      /**
       * Increases the capacity of and internally reorganizes this 
       * hashtable, in order to accommodate and access its entries more 
       * efficiently.  This method is called automatically when the 
       * number of keys in the hashtable exceeds this hashtable's capacity 
       * and load factor. 
       */
      private void rehash() {
  	int oldCapacity = table.length;
  	Entry oldMap[] = table;
  
  	int newCapacity = oldCapacity * 2 + 1;
  	Entry newMap[] = new Entry[newCapacity];
  
  	threshold = (int)(newCapacity * loadFactor);
  	table = newMap;
  
  	/*
  	System.out.pr intln("rehash old=" + oldCapacity
  		+ ", new=" + newCapacity
  		+ ", thresh=" + threshold
  		+ ", count=" + count);
  	*/
  
  	for (int i = oldCapacity ; i-- > 0 ;) {
  	    for (Entry old = oldMap[i] ; old != null ; ) {
  		Entry e = old;
  		old = old.next;
  
  		int index = (e.hash & 0x7FFFFFFF) % newCapacity;
  		e.next = newMap[index];
  		newMap[index] = e;
  	    }
  	}
      }
  
      /**
       * Maps the specified <code>key</code> to the specified 
       * <code>value</code> in this hashtable. Neither the key nor the 
       * value can be <code>null</code>. 
       *
       * <P>The value can be retrieved by calling the <code>get</code> method 
       * with a key that is equal to the original key. 
       */
      public Object put(Object key, Object value) {
  	// Make sure the value is not null
  	if (value == null) {
  	    throw new NullPointerException();
  	}
  
  	// Makes sure the key is not already in the hashtable.
  	Entry tab[] = table;
  	int hash = key.hashCode();
  	int index = (hash & 0x7FFFFFFF) % tab.length;
  	for (Entry e = tab[index] ; e != null ; e = e.next) {
  	    // if ((e.hash == hash) && e.key.equals(key)) {
  	    if ((e.hash == hash) && (e.key == key)) {
  		Object old = e.value;
  		e.value = value;
  		return old;
  	    }
  	}
  
  	if (count >= threshold) {
  	    // Rehash the table if the threshold is exceeded
  	    rehash();
  
              tab = table;
              index = (hash & 0x7FFFFFFF) % tab.length;
  	} 
  
  	// Creates the new entry.
  	Entry e = new Entry(hash, key, value, tab[index]);
  	tab[index] = e;
  	count++;
  	return null;
      }
  
      public void remove(Object o) {
  	
      }
  
      /**
       * Hashtable collision list.
       */
      private static class Entry {
  	int	hash;
  	Object	key;
  	Object	value;
  	Entry	next;
  
  	protected Entry(int hash, Object key, Object value, Entry next) {
  	    this.hash = hash;
  	    this.key = key;
  	    this.value = value;
  	    this.next = next;
  	}
      }
  }
  
  
  
  1.1                  jakarta-tomcat/src/share/org/apache/tomcat/util/collections/package.html
  
  Index: package.html
  ===================================================================
  <html>
  <head>
  <title>util.collections</title>
  <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
  </head>
  
  <body bgcolor="#FFFFFF">
  <h1>Specialized collections</h1>
  
  This package includes a number of special collections, tunned for server-side
  applications. 
  
  The utils are not tomcat specific, but use MessageBytes and few other 
  top-level utils.
  
  </body>
  </html>