src/main/org/apache/tools/ant/types/Path.java - ant - Git at Google

 /*
  * The Apache Software License, Version 1.1
  *
  * Copyright (c) 2000-2002 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", "Ant", 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/>.
  */

 package org.apache.tools.ant.types;

 import org.apache.tools.ant.BuildException;
 import org.apache.tools.ant.DirectoryScanner;
 import org.apache.tools.ant.Project;
 import org.apache.tools.ant.PathTokenizer;
 import org.apache.tools.ant.util.JavaEnvUtils;

 import java.io.File;

 import java.util.Enumeration;
 import java.util.Locale;
 import java.util.Stack;
 import java.util.Vector;


 /**
  * This object represents a path as used by CLASSPATH or PATH
  * environment variable.
  * <p>
  * <code>
  * &lt;sometask&gt;<br>
  * &nbsp;&nbsp;&lt;somepath&gt;<br>
  * &nbsp;&nbsp;&nbsp;&nbsp;&lt;pathelement location="/path/to/file.jar" /&gt;<br>
  * &nbsp;&nbsp;&nbsp;&nbsp;&lt;pathelement path="/path/to/file2.jar:/path/to/class2;/path/to/class3" /&gt;<br>
  * &nbsp;&nbsp;&nbsp;&nbsp;&lt;pathelement location="/path/to/file3.jar" /&gt;<br>
  * &nbsp;&nbsp;&nbsp;&nbsp;&lt;pathelement location="/path/to/file4.jar" /&gt;<br>
  * &nbsp;&nbsp;&lt;/somepath&gt;<br>
  * &lt;/sometask&gt;<br>
  * </code>
  * <p>
  * The object implemention <code>sometask</code> must provide a method called
  * <code>createSomepath</code> which returns an instance of <code>Path</code>.
  * Nested path definitions are handled by the Path object and must be labeled
  * <code>pathelement</code>.<p>
  *
  * The path element takes a parameter <code>path</code> which will be parsed
  * and split into single elements. It will usually be used
  * to define a path from an environment variable.
  *
  * @author Thomas.Haas@softwired-inc.com
  * @author <a href="mailto:stefan.bodewig@epost.de">Stefan Bodewig</a>
  */

 public class Path extends DataType implements Cloneable {

     private Vector elements;

     /** The system classspath as a Path object */
     public static Path systemClasspath =
         new Path(null, System.getProperty("java.class.path"));


     /**
      * Helper class, holds the nested <code>&lt;pathelement&gt;</code> values.
      */
     public class PathElement {
         private String[] parts;

         public void setLocation(File loc) {
             parts = new String[] {translateFile(loc.getAbsolutePath())};
         }

         public void setPath(String path) {
             parts = Path.translatePath(getProject(), path);
         }

         public String[] getParts() {
             return parts;
         }
     }

     /**
      * Invoked by IntrospectionHelper for <code>setXXX(Path p)</code>
      * attribute setters.
      */
     public Path(Project p, String path) {
         this(p);
         createPathElement().setPath(path);
     }

     public Path(Project project) {
         setProject(project);
         elements = new Vector();
     }

     /**
      * Adds a element definition to the path.
      * @param location the location of the element to add (must not be
      * <code>null</code> nor empty.
      */
     public void setLocation(File location) throws BuildException {
         if (isReference()) {
             throw tooManyAttributes();
         }
         createPathElement().setLocation(location);
     }


     /**
      * Parses a path definition and creates single PathElements.
      * @param path the path definition.
      */
     public void setPath(String path) throws BuildException {
         if (isReference()) {
             throw tooManyAttributes();
         }
         createPathElement().setPath(path);
     }

     /**
      * Makes this instance in effect a reference to another Path instance.
      *
      * <p>You must not set another attribute or nest elements inside
      * this element if you make it a reference.</p>
      */
     public void setRefid(Reference r) throws BuildException {
         if (!elements.isEmpty()) {
             throw tooManyAttributes();
         }
         elements.addElement(r);
         super.setRefid(r);
     }

     /**
      * Creates the nested <code>&lt;pathelement&gt;</code> element.
      */
     public PathElement createPathElement() throws BuildException {
         if (isReference()) {
             throw noChildrenAllowed();
         }
         PathElement pe = new PathElement();
         elements.addElement(pe);
         return pe;
     }

     /**
      * Adds a nested <code>&lt;fileset&gt;</code> element.
      */
     public void addFileset(FileSet fs) throws BuildException {
         if (isReference()) {
             throw noChildrenAllowed();
         }
         elements.addElement(fs);
         checked = false;
     }

     /**
      * Adds a nested <code>&lt;filelist&gt;</code> element.
      */
     public void addFilelist(FileList fl) throws BuildException {
         if (isReference()) {
             throw noChildrenAllowed();
         }
         elements.addElement(fl);
         checked = false;
     }

     /**
      * Adds a nested <code>&lt;dirset&gt;</code> element.
      */
     public void addDirset(DirSet dset) throws BuildException {
         if (isReference()) {
             throw noChildrenAllowed();
         }
         elements.addElement(dset);
         checked = false;
     }

     /**
      * Creates a nested <code>&lt;path&gt;</code> element.
      */
     public Path createPath() throws BuildException {
         if (isReference()) {
             throw noChildrenAllowed();
         }
         Path p = new Path(getProject());
         elements.addElement(p);
         checked = false;
         return p;
     }

     /**
      * Append the contents of the other Path instance to this.
      */
     public void append(Path other) {
         if (other == null) {
             return;
         }
         String[] l = other.list();
         for (int i = 0; i < l.length; i++) {
             if (elements.indexOf(l[i]) == -1) {
                 elements.addElement(l[i]);
             }
         }
     }

      /**
      * Adds the components on the given path which exist to this
      * Path. Components that don't exist, aren't added.
      *
      * @param source - source path whose components are examined for existence
      */
     public void addExisting(Path source) {
         String[] list = source.list();
         for (int i = 0; i < list.length; i++) {
             File f = null;
             if (getProject() != null) {
                 f = getProject().resolveFile(list[i]);
             } else {
                 f = new File(list[i]);
             }

             if (f.exists()) {
                 setLocation(f);
             } else {
                 log("dropping " + f + " from path as it doesn't exist",
                     Project.MSG_VERBOSE);
             }
         }
     }

     /**
      * Returns all path elements defined by this and nested path objects.
      * @return list of path elements.
      */
     public String[] list() {
         if (!checked) {
             // make sure we don't have a circular reference here
             Stack stk = new Stack();
             stk.push(this);
             dieOnCircularReference(stk, getProject());
         }

         Vector result = new Vector(2 * elements.size());
         for (int i = 0; i < elements.size(); i++) {
             Object o = elements.elementAt(i);
             if (o instanceof Reference) {
                 Reference r = (Reference) o;
                 o = r.getReferencedObject(getProject());
                 // we only support references to paths right now
                 if (!(o instanceof Path)) {
                     String msg = r.getRefId() + " doesn\'t denote a path";
                     throw new BuildException(msg);
                 }
             }

             if (o instanceof String) {
                 // obtained via append
                 addUnlessPresent(result, (String) o);
             } else if (o instanceof PathElement) {
                 String[] parts = ((PathElement) o).getParts();
                 if (parts == null) {
                     throw new BuildException("You must either set location or"
                         + " path on <pathelement>");
                 }
                 for (int j = 0; j < parts.length; j++) {
                     addUnlessPresent(result, parts[j]);
                 }
             } else if (o instanceof Path) {
                 Path p = (Path) o;
                 if (p.getProject() == null) {
                     p.setProject(getProject());
                 }
                 String[] parts = p.list();
                 for (int j = 0; j < parts.length; j++) {
                     addUnlessPresent(result, parts[j]);
                 }
             } else if (o instanceof DirSet) {
                 DirSet dset = (DirSet) o;
                 DirectoryScanner ds = dset.getDirectoryScanner(getProject());
                 String[] s = ds.getIncludedDirectories();
                 File dir = dset.getDir(getProject());
                 addUnlessPresent(result, dir, s);
             } else if (o instanceof FileSet) {
                 FileSet fs = (FileSet) o;
                 DirectoryScanner ds = fs.getDirectoryScanner(getProject());
                 String[] s = ds.getIncludedFiles();
                 File dir = fs.getDir(getProject());
                 addUnlessPresent(result, dir, s);
             } else if (o instanceof FileList) {
                 FileList fl = (FileList) o;
                 String[] s = fl.getFiles(getProject());
                 File dir = fl.getDir(getProject());
                 addUnlessPresent(result, dir, s);
             }
         }
         String[] res = new String[result.size()];
         result.copyInto(res);
         return res;
     }


     /**
      * Returns a textual representation of the path, which can be used as
      * CLASSPATH or PATH environment variable definition.
      * @return a textual representation of the path.
      */
     public String toString() {
         final String[] list = list();

         // empty path return empty string
         if (list.length == 0) {
             return "";
         }

         // path containing one or more elements
         final StringBuffer result = new StringBuffer(list[0].toString());
         for (int i = 1; i < list.length; i++) {
             result.append(File.pathSeparatorChar);
             result.append(list[i]);
         }

         return result.toString();
     }

     /**
      * Splits a PATH (with : or ; as separators) into its parts.
      */
     public static String[] translatePath(Project project, String source) {
         final Vector result = new Vector();
         if (source == null) {
           return new String[0];
         }

         PathTokenizer tok = new PathTokenizer(source);
         StringBuffer element = new StringBuffer();
         while (tok.hasMoreTokens()) {
             element.setLength(0);
             String pathElement = tok.nextToken();
             try {
                 element.append(resolveFile(project, pathElement));
             } catch (BuildException e) {
                 project.log("Dropping path element " + pathElement
                     + " as it is not valid relative to the project",
                     Project.MSG_VERBOSE);
             }
             for (int i = 0; i < element.length(); i++) {
                 translateFileSep(element, i);
             }
             result.addElement(element.toString());
         }
         String[] res = new String[result.size()];
         result.copyInto(res);
         return res;
     }

     /**
      * Returns its argument with all file separator characters
      * replaced so that they match the local OS conventions.
      */
     public static String translateFile(String source) {
         if (source == null) {
           return "";
         }

         final StringBuffer result = new StringBuffer(source);
         for (int i = 0; i < result.length(); i++) {
             translateFileSep(result, i);
         }

         return result.toString();
     }

     /**
      * Translates all occurrences of / or \ to correct separator of the
      * current platform and returns whether it had to do any
      * replacements.
      */
     protected static boolean translateFileSep(StringBuffer buffer, int pos) {
         if (buffer.charAt(pos) == '/' || buffer.charAt(pos) == '\\') {
             buffer.setCharAt(pos, File.separatorChar);
             return true;
         }
         return false;
     }

     /**
      * How many parts does this Path instance consist of.
      */
     public int size() {
         return list().length;
     }

     /**
      * Return a Path that holds the same elements as this instance.
      */
     public Object clone() {
         Path p = new Path(getProject());
         p.append(this);
         return p;
     }

     /**
      * Overrides the version of DataType to recurse on all DataType
      * child elements that may have been added.
      */
     protected void dieOnCircularReference(Stack stk, Project p)
         throws BuildException {

         if (checked) {
             return;
         }

         Enumeration enum = elements.elements();
         while (enum.hasMoreElements()) {
             Object o = enum.nextElement();
             if (o instanceof Reference) {
                 o = ((Reference) o).getReferencedObject(p);
             }

             if (o instanceof DataType) {
                 if (stk.contains(o)) {
                     throw circularReference();
                 } else {
                     stk.push(o);
                     ((DataType) o).dieOnCircularReference(stk, p);
                     stk.pop();
                 }
             }
         }
         checked = true;
     }

     /**
      * Resolve a filename with Project's help - if we know one that is.
      *
      * <p>Assume the filename is absolute if project is null.</p>
      */
     private static String resolveFile(Project project, String relativeName) {
         if (project != null) {
             File f = project.resolveFile(relativeName);
             return f.getAbsolutePath();
         }
         return relativeName;
     }

     /**
      * Adds a String to the Vector if it isn't already included.
      */
     private static void addUnlessPresent(Vector v, String s) {
         if (v.indexOf(s) == -1) {
             v.addElement(s);
         }
     }

     /**
      * Adds absolute path names of listed files in the given directory
      * to the Vector if they are not already included.
      */
     private static void addUnlessPresent(Vector v, File dir, String[] s) {
         for (int j = 0; j < s.length; j++) {
             File d = new File(dir, s[j]);
             String absolutePath = d.getAbsolutePath();
             addUnlessPresent(v, translateFile(absolutePath));
         }
     }

     /**
      * Concatenates the system class path in the order specified by
      * the ${build.sysclasspath} property - using &quot;last&quot; as
      * default value.
      */
     public Path concatSystemClasspath() {
         return concatSystemClasspath("last");
     }

     /**
      * Concatenates the system class path in the order specified by
      * the ${build.sysclasspath} property - using the supplied value
      * if ${build.sysclasspath} has not been set.
      */
     public Path concatSystemClasspath(String defValue) {

         Path result = new Path(getProject());

         String order = defValue;
         if (getProject() != null) {
             String o = getProject().getProperty("build.sysclasspath");
             if (o != null) {
                 order = o;
             }
         }

         if (order.equals("only")) {
             // only: the developer knows what (s)he is doing
             result.addExisting(Path.systemClasspath);

         } else if (order.equals("first")) {
             // first: developer could use a little help
             result.addExisting(Path.systemClasspath);
             result.addExisting(this);

         } else if (order.equals("ignore")) {
             // ignore: don't trust anyone
             result.addExisting(this);

         } else {
             // last: don't trust the developer
             if (!order.equals("last")) {
                 log("invalid value for build.sysclasspath: " + order,
                     Project.MSG_WARN);
             }

             result.addExisting(this);
             result.addExisting(Path.systemClasspath);
         }


         return result;

     }

     /**
      * Add the Java Runtime classes to this Path instance.
      */
     public void addJavaRuntime() {
         if (System.getProperty("java.vendor").toLowerCase(Locale.US).indexOf("microsoft") >= 0) {
             // Pull in *.zip from packages directory
             FileSet msZipFiles = new FileSet();
             msZipFiles.setDir(new File(System.getProperty("java.home")
                 + File.separator + "Packages"));
             msZipFiles.setIncludes("*.ZIP");
             addFileset(msZipFiles);
         } else if ("Kaffe".equals(System.getProperty("java.vm.name"))) {
             FileSet kaffeJarFiles = new FileSet();
             kaffeJarFiles.setDir(new File(System.getProperty("java.home")
                                           + File.separator + "share"
                                           + File.separator + "kaffe"));

             kaffeJarFiles.setIncludes("*.jar");
             addFileset(kaffeJarFiles);
         } else if (JavaEnvUtils.isJavaVersion(JavaEnvUtils.JAVA_1_1)) {
             addExisting(new Path(null,
                                  System.getProperty("java.home")
                                  + File.separator + "lib"
                                  + File.separator
                                  + "classes.zip"));
         } else {
             // JDK > 1.1 seems to set java.home to the JRE directory.
             addExisting(new Path(null,
                                  System.getProperty("java.home")
                                  + File.separator + "lib"
                                  + File.separator + "rt.jar"));
             // Just keep the old version as well and let addExisting
             // sort it out.
             addExisting(new Path(null,
                                  System.getProperty("java.home")
                                  + File.separator + "jre"
                                  + File.separator + "lib"
                                  + File.separator + "rt.jar"));

             // Added for MacOS X
             addExisting(new Path(null,
                                  System.getProperty("java.home")
                                  + File.separator + ".."
                                  + File.separator + "Classes"
                                  + File.separator + "classes.jar"));
             addExisting(new Path(null,
                                  System.getProperty("java.home")
                                  + File.separator + ".."
                                  + File.separator + "Classes"
                                  + File.separator + "ui.jar"));
         }
     }

     /**
      * Emulation of extdirs feature in java >= 1.2.
      * This method adds all files in the given
      * directories (but not in sub-directories!) to the classpath,
      * so that you don't have to specify them all one by one.
      * @param extdirs - Path to append files to
      */
     public void addExtdirs(Path extdirs) {
         if (extdirs == null) {
             String extProp = System.getProperty("java.ext.dirs");
             if (extProp != null) {
                 extdirs = new Path(getProject(), extProp);
             } else {
                 return;
             }
         }

         String[] dirs = extdirs.list();
         for (int i = 0; i < dirs.length; i++) {
             File dir = getProject().resolveFile(dirs[i]);
             if (dir.exists() && dir.isDirectory()) {
                 FileSet fs = new FileSet();
                 fs.setDir(dir);
                 fs.setIncludes("*");
                 addFileset(fs);
             }
         }
     }
 }
	/*
	* The Apache Software License, Version 1.1
	*
	* Copyright (c) 2000-2002 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", "Ant", 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/>.
	*/

	package org.apache.tools.ant.types;

	import org.apache.tools.ant.BuildException;
	import org.apache.tools.ant.DirectoryScanner;
	import org.apache.tools.ant.Project;
	import org.apache.tools.ant.PathTokenizer;
	import org.apache.tools.ant.util.JavaEnvUtils;

	import java.io.File;

	import java.util.Enumeration;
	import java.util.Locale;
	import java.util.Stack;
	import java.util.Vector;



	/**
	* This object represents a path as used by CLASSPATH or PATH
	* environment variable.
	* <p>
	* <code>
	* <sometask><br>
	*   <somepath><br>
	*     <pathelement location="/path/to/file.jar" /><br>
	*     <pathelement path="/path/to/file2.jar:/path/to/class2;/path/to/class3" /><br>
	*     <pathelement location="/path/to/file3.jar" /><br>
	*     <pathelement location="/path/to/file4.jar" /><br>
	*   </somepath><br>
	* </sometask><br>
	* </code>
	* <p>
	* The object implemention <code>sometask</code> must provide a method called
	* <code>createSomepath</code> which returns an instance of <code>Path</code>.
	* Nested path definitions are handled by the Path object and must be labeled
	* <code>pathelement</code>.<p>
	*
	* The path element takes a parameter <code>path</code> which will be parsed
	* and split into single elements. It will usually be used
	* to define a path from an environment variable.
	*
	* @author Thomas.Haas@softwired-inc.com
	* @author <a href="mailto:stefan.bodewig@epost.de">Stefan Bodewig</a>
	*/

	public class Path extends DataType implements Cloneable {

	private Vector elements;

	/** The system classspath as a Path object */
	public static Path systemClasspath =
	new Path(null, System.getProperty("java.class.path"));


	/**
	* Helper class, holds the nested <code><pathelement></code> values.
	*/
	public class PathElement {
	private String[] parts;

	public void setLocation(File loc) {
	parts = new String[] {translateFile(loc.getAbsolutePath())};
	}

	public void setPath(String path) {
	parts = Path.translatePath(getProject(), path);
	}

	public String[] getParts() {
	return parts;
	}
	}

	/**
	* Invoked by IntrospectionHelper for <code>setXXX(Path p)</code>
	* attribute setters.
	*/
	public Path(Project p, String path) {
	this(p);
	createPathElement().setPath(path);
	}

	public Path(Project project) {
	setProject(project);
	elements = new Vector();
	}

	/**
	* Adds a element definition to the path.
	* @param location the location of the element to add (must not be
	* <code>null</code> nor empty.
	*/
	public void setLocation(File location) throws BuildException {
	if (isReference()) {
	throw tooManyAttributes();
	}
	createPathElement().setLocation(location);
	}


	/**
	* Parses a path definition and creates single PathElements.
	* @param path the path definition.
	*/
	public void setPath(String path) throws BuildException {
	if (isReference()) {
	throw tooManyAttributes();
	}
	createPathElement().setPath(path);
	}

	/**
	* Makes this instance in effect a reference to another Path instance.
	*
	* <p>You must not set another attribute or nest elements inside
	* this element if you make it a reference.</p>
	*/
	public void setRefid(Reference r) throws BuildException {
	if (!elements.isEmpty()) {
	throw tooManyAttributes();
	}
	elements.addElement(r);
	super.setRefid(r);
	}

	/**
	* Creates the nested <code><pathelement></code> element.
	*/
	public PathElement createPathElement() throws BuildException {
	if (isReference()) {
	throw noChildrenAllowed();
	}
	PathElement pe = new PathElement();
	elements.addElement(pe);
	return pe;
	}

	/**
	* Adds a nested <code><fileset></code> element.
	*/
	public void addFileset(FileSet fs) throws BuildException {
	if (isReference()) {
	throw noChildrenAllowed();
	}
	elements.addElement(fs);
	checked = false;
	}

	/**
	* Adds a nested <code><filelist></code> element.
	*/
	public void addFilelist(FileList fl) throws BuildException {
	if (isReference()) {
	throw noChildrenAllowed();
	}
	elements.addElement(fl);
	checked = false;
	}

	/**
	* Adds a nested <code><dirset></code> element.
	*/
	public void addDirset(DirSet dset) throws BuildException {
	if (isReference()) {
	throw noChildrenAllowed();
	}
	elements.addElement(dset);
	checked = false;
	}

	/**
	* Creates a nested <code><path></code> element.
	*/
	public Path createPath() throws BuildException {
	if (isReference()) {
	throw noChildrenAllowed();
	}
	Path p = new Path(getProject());
	elements.addElement(p);
	checked = false;
	return p;
	}

	/**
	* Append the contents of the other Path instance to this.
	*/
	public void append(Path other) {
	if (other == null) {
	return;
	}
	String[] l = other.list();
	for (int i = 0; i < l.length; i++) {
	if (elements.indexOf(l[i]) == -1) {
	elements.addElement(l[i]);
	}
	}
	}

	/**
	* Adds the components on the given path which exist to this
	* Path. Components that don't exist, aren't added.
	*
	* @param source - source path whose components are examined for existence
	*/
	public void addExisting(Path source) {
	String[] list = source.list();
	for (int i = 0; i < list.length; i++) {
	File f = null;
	if (getProject() != null) {
	f = getProject().resolveFile(list[i]);
	} else {
	f = new File(list[i]);
	}

	if (f.exists()) {
	setLocation(f);
	} else {
	log("dropping " + f + " from path as it doesn't exist",
	Project.MSG_VERBOSE);
	}
	}
	}

	/**
	* Returns all path elements defined by this and nested path objects.
	* @return list of path elements.
	*/
	public String[] list() {
	if (!checked) {
	// make sure we don't have a circular reference here
	Stack stk = new Stack();
	stk.push(this);
	dieOnCircularReference(stk, getProject());
	}

	Vector result = new Vector(2 * elements.size());
	for (int i = 0; i < elements.size(); i++) {
	Object o = elements.elementAt(i);
	if (o instanceof Reference) {
	Reference r = (Reference) o;
	o = r.getReferencedObject(getProject());
	// we only support references to paths right now
	if (!(o instanceof Path)) {
	String msg = r.getRefId() + " doesn\'t denote a path";
	throw new BuildException(msg);
	}
	}

	if (o instanceof String) {
	// obtained via append
	addUnlessPresent(result, (String) o);
	} else if (o instanceof PathElement) {
	String[] parts = ((PathElement) o).getParts();
	if (parts == null) {
	throw new BuildException("You must either set location or"
	+ " path on <pathelement>");
	}
	for (int j = 0; j < parts.length; j++) {
	addUnlessPresent(result, parts[j]);
	}
	} else if (o instanceof Path) {
	Path p = (Path) o;
	if (p.getProject() == null) {
	p.setProject(getProject());
	}
	String[] parts = p.list();
	for (int j = 0; j < parts.length; j++) {
	addUnlessPresent(result, parts[j]);
	}
	} else if (o instanceof DirSet) {
	DirSet dset = (DirSet) o;
	DirectoryScanner ds = dset.getDirectoryScanner(getProject());
	String[] s = ds.getIncludedDirectories();
	File dir = dset.getDir(getProject());
	addUnlessPresent(result, dir, s);
	} else if (o instanceof FileSet) {
	FileSet fs = (FileSet) o;
	DirectoryScanner ds = fs.getDirectoryScanner(getProject());
	String[] s = ds.getIncludedFiles();
	File dir = fs.getDir(getProject());
	addUnlessPresent(result, dir, s);
	} else if (o instanceof FileList) {
	FileList fl = (FileList) o;
	String[] s = fl.getFiles(getProject());
	File dir = fl.getDir(getProject());
	addUnlessPresent(result, dir, s);
	}
	}
	String[] res = new String[result.size()];
	result.copyInto(res);
	return res;
	}


	/**
	* Returns a textual representation of the path, which can be used as
	* CLASSPATH or PATH environment variable definition.
	* @return a textual representation of the path.
	*/
	public String toString() {
	final String[] list = list();

	// empty path return empty string
	if (list.length == 0) {
	return "";
	}

	// path containing one or more elements
	final StringBuffer result = new StringBuffer(list[0].toString());
	for (int i = 1; i < list.length; i++) {
	result.append(File.pathSeparatorChar);
	result.append(list[i]);
	}

	return result.toString();
	}

	/**
	* Splits a PATH (with : or ; as separators) into its parts.
	*/
	public static String[] translatePath(Project project, String source) {
	final Vector result = new Vector();
	if (source == null) {
	return new String[0];
	}

	PathTokenizer tok = new PathTokenizer(source);
	StringBuffer element = new StringBuffer();
	while (tok.hasMoreTokens()) {
	element.setLength(0);
	String pathElement = tok.nextToken();
	try {
	element.append(resolveFile(project, pathElement));
	} catch (BuildException e) {
	project.log("Dropping path element " + pathElement
	+ " as it is not valid relative to the project",
	Project.MSG_VERBOSE);
	}
	for (int i = 0; i < element.length(); i++) {
	translateFileSep(element, i);
	}
	result.addElement(element.toString());
	}
	String[] res = new String[result.size()];
	result.copyInto(res);
	return res;
	}

	/**
	* Returns its argument with all file separator characters
	* replaced so that they match the local OS conventions.
	*/
	public static String translateFile(String source) {
	if (source == null) {
	return "";
	}

	final StringBuffer result = new StringBuffer(source);
	for (int i = 0; i < result.length(); i++) {
	translateFileSep(result, i);
	}

	return result.toString();
	}

	/**
	* Translates all occurrences of / or \ to correct separator of the
	* current platform and returns whether it had to do any
	* replacements.
	*/
	protected static boolean translateFileSep(StringBuffer buffer, int pos) {
	if (buffer.charAt(pos) == '/' \|\| buffer.charAt(pos) == '\\') {
	buffer.setCharAt(pos, File.separatorChar);
	return true;
	}
	return false;
	}

	/**
	* How many parts does this Path instance consist of.
	*/
	public int size() {
	return list().length;
	}

	/**
	* Return a Path that holds the same elements as this instance.
	*/
	public Object clone() {
	Path p = new Path(getProject());
	p.append(this);
	return p;
	}

	/**
	* Overrides the version of DataType to recurse on all DataType
	* child elements that may have been added.
	*/
	protected void dieOnCircularReference(Stack stk, Project p)
	throws BuildException {

	if (checked) {
	return;
	}

	Enumeration enum = elements.elements();
	while (enum.hasMoreElements()) {
	Object o = enum.nextElement();
	if (o instanceof Reference) {
	o = ((Reference) o).getReferencedObject(p);
	}

	if (o instanceof DataType) {
	if (stk.contains(o)) {
	throw circularReference();
	} else {
	stk.push(o);
	((DataType) o).dieOnCircularReference(stk, p);
	stk.pop();
	}
	}
	}
	checked = true;
	}

	/**
	* Resolve a filename with Project's help - if we know one that is.
	*
	* <p>Assume the filename is absolute if project is null.</p>
	*/
	private static String resolveFile(Project project, String relativeName) {
	if (project != null) {
	File f = project.resolveFile(relativeName);
	return f.getAbsolutePath();
	}
	return relativeName;
	}

	/**
	* Adds a String to the Vector if it isn't already included.
	*/
	private static void addUnlessPresent(Vector v, String s) {
	if (v.indexOf(s) == -1) {
	v.addElement(s);
	}
	}

	/**
	* Adds absolute path names of listed files in the given directory
	* to the Vector if they are not already included.
	*/
	private static void addUnlessPresent(Vector v, File dir, String[] s) {
	for (int j = 0; j < s.length; j++) {
	File d = new File(dir, s[j]);
	String absolutePath = d.getAbsolutePath();
	addUnlessPresent(v, translateFile(absolutePath));
	}
	}

	/**
	* Concatenates the system class path in the order specified by
	* the ${build.sysclasspath} property - using "last" as
	* default value.
	*/
	public Path concatSystemClasspath() {
	return concatSystemClasspath("last");
	}

	/**
	* Concatenates the system class path in the order specified by
	* the ${build.sysclasspath} property - using the supplied value
	* if ${build.sysclasspath} has not been set.
	*/
	public Path concatSystemClasspath(String defValue) {

	Path result = new Path(getProject());

	String order = defValue;
	if (getProject() != null) {
	String o = getProject().getProperty("build.sysclasspath");
	if (o != null) {
	order = o;
	}
	}

	if (order.equals("only")) {
	// only: the developer knows what (s)he is doing
	result.addExisting(Path.systemClasspath);

	} else if (order.equals("first")) {
	// first: developer could use a little help
	result.addExisting(Path.systemClasspath);
	result.addExisting(this);

	} else if (order.equals("ignore")) {
	// ignore: don't trust anyone
	result.addExisting(this);

	} else {
	// last: don't trust the developer
	if (!order.equals("last")) {
	log("invalid value for build.sysclasspath: " + order,
	Project.MSG_WARN);
	}

	result.addExisting(this);
	result.addExisting(Path.systemClasspath);
	}


	return result;

	}

	/**
	* Add the Java Runtime classes to this Path instance.
	*/
	public void addJavaRuntime() {
	if (System.getProperty("java.vendor").toLowerCase(Locale.US).indexOf("microsoft") >= 0) {
	// Pull in *.zip from packages directory
	FileSet msZipFiles = new FileSet();
	msZipFiles.setDir(new File(System.getProperty("java.home")
	+ File.separator + "Packages"));
	msZipFiles.setIncludes("*.ZIP");
	addFileset(msZipFiles);
	} else if ("Kaffe".equals(System.getProperty("java.vm.name"))) {
	FileSet kaffeJarFiles = new FileSet();
	kaffeJarFiles.setDir(new File(System.getProperty("java.home")
	+ File.separator + "share"
	+ File.separator + "kaffe"));

	kaffeJarFiles.setIncludes("*.jar");
	addFileset(kaffeJarFiles);
	} else if (JavaEnvUtils.isJavaVersion(JavaEnvUtils.JAVA_1_1)) {
	addExisting(new Path(null,
	System.getProperty("java.home")
	+ File.separator + "lib"
	+ File.separator
	+ "classes.zip"));
	} else {
	// JDK > 1.1 seems to set java.home to the JRE directory.
	addExisting(new Path(null,
	System.getProperty("java.home")
	+ File.separator + "lib"
	+ File.separator + "rt.jar"));
	// Just keep the old version as well and let addExisting
	// sort it out.
	addExisting(new Path(null,
	System.getProperty("java.home")
	+ File.separator + "jre"
	+ File.separator + "lib"
	+ File.separator + "rt.jar"));

	// Added for MacOS X
	addExisting(new Path(null,
	System.getProperty("java.home")
	+ File.separator + ".."
	+ File.separator + "Classes"
	+ File.separator + "classes.jar"));
	addExisting(new Path(null,
	System.getProperty("java.home")
	+ File.separator + ".."
	+ File.separator + "Classes"
	+ File.separator + "ui.jar"));
	}
	}

	/**
	* Emulation of extdirs feature in java >= 1.2.
	* This method adds all files in the given
	* directories (but not in sub-directories!) to the classpath,
	* so that you don't have to specify them all one by one.
	* @param extdirs - Path to append files to
	*/
	public void addExtdirs(Path extdirs) {
	if (extdirs == null) {
	String extProp = System.getProperty("java.ext.dirs");
	if (extProp != null) {
	extdirs = new Path(getProject(), extProp);
	} else {
	return;
	}
	}

	String[] dirs = extdirs.list();
	for (int i = 0; i < dirs.length; i++) {
	File dir = getProject().resolveFile(dirs[i]);
	if (dir.exists() && dir.isDirectory()) {
	FileSet fs = new FileSet();
	fs.setDir(dir);
	fs.setIncludes("*");
	addFileset(fs);
	}
	}
	}
	}