src/main/org/apache/tools/ant/taskdefs/Property.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.taskdefs;

 import org.apache.tools.ant.Task;
 import org.apache.tools.ant.BuildException;
 import org.apache.tools.ant.Project;
 import org.apache.tools.ant.AntClassLoader;
 import org.apache.tools.ant.ProjectHelper;
 import org.apache.tools.ant.types.Path;
 import org.apache.tools.ant.types.Reference;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.Properties;
 import java.util.Vector;
 import java.util.Enumeration;

 /**
  * Sets a property by name, or set of properties (from file or
  * resource) in the project.  </p>
  * Properties are immutable: whoever sets a property first freezes it for the
  * rest of the build; they are most definately not variable.
  * <p>There are five ways to set properties:</p>
  * <ul>
  *   <li>By supplying both the <i>name</i> and <i>value</i> attribute.</li>
  *   <li>By supplying both the <i>name</i> and <i>refid</i> attribute.</li>
  *   <li>By setting the <i>file</i> attribute with the filename of the property
  *     file to load. This property file has the format as defined by the file used
  *     in the class java.util.Properties.</li>
  *   <li>By setting the <i>resource</i> attribute with the resource name of the
  *     property file to load. This property file has the format as defined by the
  *     file used in the class java.util.Properties.</li>
  *   <li>By setting the <i>environment</i> attribute with a prefix to use.
  *     Properties will be defined for every environment variable by
  *     prefixing the supplied name and a period to the name of the variable.</li>
  * </ul>
  * <p>Although combinations of these ways are possible, only one should be used
  * at a time. Problems might occur with the order in which properties are set, for
  * instance.</p>
  * <p>The value part of the properties being set, might contain references to other
  * properties. These references are resolved at the time these properties are set.
  * This also holds for properties loaded from a property file.</p>
  * Properties are case sensitive.
  *
  * @author costin@dnt.ro
  * @author <a href="mailto:rubys@us.ibm.com">Sam Ruby</a>
  * @author <a href="mailto:glennm@ca.ibm.com">Glenn McAllister</a>
  * @since Ant 1.1
  */
 public class Property extends Task {

     protected String name;
     protected String value;
     protected File file;
     protected String resource;
     protected Path classpath;
     protected String env;
     protected Reference ref;
     protected String prefix;
     private Project fallback;

     protected boolean userProperty; // set read-only properties

     public Property() {
         this(false);
     }

     /**
      * @since Ant 1.5
      */
     protected Property(boolean userProperty) {
         this(userProperty, null);
     }

     /**
      * @since Ant 1.5
      */
     protected Property(boolean userProperty, Project fallback) {
         this.userProperty = userProperty;
         this.fallback = fallback;
     }

     /**
      * sets the name of the property to set.
      * @param name property name
      */
     public void setName(String name) {
         this.name = name;
     }

     public String getName() {
         return name;
     }

     /**
      * Sets the property to the absolute filename of the
      * given file. If the value of this attribute is an absolute path, it
      * is left unchanged (with / and \ characters converted to the
      * current platforms conventions). Otherwise it is taken as a path
      * relative to the project's basedir and expanded.
      * @param location path to set
      */
     public void setLocation(File location) {
         setValue(location.getAbsolutePath());
     }

     /**
      * Sets the value of the property.
      * @param value value to assign
      */

     public void setValue(String value) {
         this.value = value;
     }


     public String getValue() {
         return value;
     }

     /**
      * the filename of a property file to load.
      *@param file filename
      */
     public void setFile(File file) {
         this.file = file;
     }

     public File getFile() {
         return file;
     }

     /**
      * Prefix to apply to properties loaded using <code>file</code>
      * or <code>resource</code>.
      * A "." is appended to the prefix if not specified.
      * @param prefix prefix string
      * @since Ant 1.5
      */
     public void setPrefix(String prefix) {
         this.prefix = prefix;
         if (!prefix.endsWith(".")) {
             this.prefix += ".";
         }
     }

     /**
      * @since Ant 1.5
      */
     public String getPrefix() {
         return prefix;
     }

     /**
      * Sets a reference to an Ant datatype
      * declared elsewhere.
      * Only yields reasonable results for references
      * PATH like structures or properties.
      * @param ref reference
      */
     public void setRefid(Reference ref) {
         this.ref = ref;
     }

     public Reference getRefid() {
         return ref;
     }

     /**
      * the resource name of a property file to load
      * @param resource resource on classpath
      */
     public void setResource(String resource) {
         this.resource = resource;
     }

     public String getResource() {
         return resource;
     }

     /**
     * the prefix to use when retrieving environment variables.
     * Thus if you specify environment=&quot;myenv&quot;
     * you will be able to access OS-specific
     * environment variables via property names &quot;myenv.PATH&quot; or
     * &quot;myenv.TERM&quot;.
     * <p>
     * Note that if you supply a property name with a final
     * &quot;.&quot; it will not be doubled. ie environment=&quot;myenv.&quot; will still
     * allow access of environment variables through &quot;myenv.PATH&quot; and
     * &quot;myenv.TERM&quot;. This functionality is currently only implemented
     * on select platforms. Feel free to send patches to increase the number of platforms
     * this functionality is supported on ;).<br>
     * Note also that properties are case sensitive, even if the
     * environment variables on your operating system are not, e.g. it
     * will be ${env.Path} not ${env.PATH} on Windows 2000.
     * @param env prefix
     */

     public void setEnvironment(String env) {
         this.env = env;
     }

     /**
      * @since Ant 1.5
      */
     public String getEnvironment() {
         return env;
     }


     /**
      * The classpath to use when looking up a resource.
      * @param classpath to add to any existing classpath
      */

     public void setClasspath(Path classpath) {
         if (this.classpath == null) {
             this.classpath = classpath;
         } else {
             this.classpath.append(classpath);
         }
     }

     /**
      * The classpath to use when looking up a resource.
      */
     public Path createClasspath() {
         if (this.classpath == null) {
             this.classpath = new Path(project);
         }
         return this.classpath.createPath();
     }

     /**
      * the classpath to use when lookingup a resource,
      * given as reference to a &lt;path&gt; defined elsewhere
     public void setClasspathRef(Reference r) {
         createClasspath().setRefid(r);
     }

     /**
      * @since Ant 1.5
      */
     public Path getClasspath() {
         return classpath;
     }

     /**
      * @deprecated This was never a supported feature and has been
      * deprecated without replacement
      * @ant.setter skip="true"
      */
     public void setUserProperty(boolean userProperty) {
         log("DEPRECATED: Ignoring request to set user property in Property"
             + " task.", Project.MSG_WARN);
     }

     /**
      * get the value of this property
      * @return the current value or the empty string
      */
     public String toString() {
         return value == null ? "" : value;
     }

     /**
      * set the property in the project to the value.
      * if the task was give a file, resource or env attribute
      * here is where it is loaded
      */
     public void execute() throws BuildException {
         if (name != null) {
             if (value == null && ref == null) {
                 throw new BuildException("You must specify value, location or "
                                          + "refid with the name attribute",
                                          location);
             }
         } else {
             if (file == null && resource == null && env == null) {
                 throw new BuildException("You must specify file, resource or "
                                          + "environment when not using the "
                                          + "name attribute", location);
             }
         }

         if (file == null && resource == null && prefix != null) {
             throw new BuildException("Prefix is only valid when loading from "
                                      + "a file or resource", location);
         }

         if ((name != null) && (value != null)) {
             addProperty(name, value);
         }

         if (file != null) {
             loadFile(file);
         }

         if (resource != null) {
             loadResource(resource);
         }

         if (env != null) {
             loadEnvironment(env);
         }

         if ((name != null) && (ref != null)) {
             try {
                 addProperty(name,
                             ref.getReferencedObject(getProject()).toString());
             } catch (BuildException be) {
                 if (fallback != null) {
                     addProperty(name,
                                 ref.getReferencedObject(fallback).toString());
                 } else {
                     throw be;
                 }
             }
         }
     }

     /**
      * load properties from a file
      * @param file file to load
      */
     protected void loadFile(File file) throws BuildException {
         Properties props = new Properties();
         log("Loading " + file.getAbsolutePath(), Project.MSG_VERBOSE);
         try {
             if (file.exists()) {
                 FileInputStream fis = new FileInputStream(file);
                 try {
                     props.load(fis);
                 } finally {
                     if (fis != null) {
                         fis.close();
                     }
                 }
                 addProperties(props);
             } else {
                 log("Unable to find property file: " + file.getAbsolutePath(),
                     Project.MSG_VERBOSE);
             }
         } catch (IOException ex) {
             throw new BuildException(ex, location);
         }
     }

     /**
      * load properties from a resource in the current classpath
      * @param name name of resource to load
      */
     protected void loadResource(String name) {
         Properties props = new Properties();
         log("Resource Loading " + name, Project.MSG_VERBOSE);
         InputStream is = null;
         try {
             ClassLoader cL = null;

             if (classpath != null) {
                 cL = new AntClassLoader(project, classpath);
             } else {
                 cL = this.getClass().getClassLoader();
             }

             if (cL == null) {
                 is = ClassLoader.getSystemResourceAsStream(name);
             } else {
                 is = cL.getResourceAsStream(name);
             }

             if (is != null) {
                 props.load(is);
                 addProperties(props);
             } else {
                 log("Unable to find resource " + name, Project.MSG_WARN);
             }
         } catch (IOException ex) {
             throw new BuildException(ex, location);
         } finally {
             if (is != null) {
                 try {
                     is.close();
                 } catch (IOException e) {}
             }
         }

     }

     /**
      * load the environment values
      * @param prefix prefix to place before them
      */
     protected void loadEnvironment(String prefix) {
         Properties props = new Properties();
         if (!prefix.endsWith(".")) {
             prefix += ".";
         }
         log("Loading Environment " + prefix, Project.MSG_VERBOSE);
         Vector osEnv = Execute.getProcEnvironment();
         for (Enumeration e = osEnv.elements(); e.hasMoreElements();) {
             String entry = (String) e.nextElement();
             int pos = entry.indexOf('=');
             if (pos == -1) {
                 log("Ignoring: " + entry, Project.MSG_WARN);
             } else {
                 props.put(prefix + entry.substring(0, pos),
                 entry.substring(pos + 1));
             }
         }
         addProperties(props);
     }

     /**
      * iterate through a set of properties,
      * resolve them then assign them
      */
     protected void addProperties(Properties props) {
         resolveAllProperties(props);
         Enumeration e = props.keys();
         while (e.hasMoreElements()) {
             String name = (String) e.nextElement();
             String value = props.getProperty(name);

             String v = project.replaceProperties(value);

             if (prefix != null) {
                 name = prefix + name;
             }

             addProperty(name, v);
         }
     }

     /**
      * add a name value pair to the project property set
      * @param n name of property
      * @param v value to set
      */
     protected void addProperty(String n, String v) {
         if (userProperty) {
             if (project.getUserProperty(n) == null) {
                 project.setInheritedProperty(n, v);
             } else {
                 log("Override ignored for " + n, Project.MSG_VERBOSE);
             }
         } else {
             project.setNewProperty(n, v);
         }
     }

     /**
      * resolve properties inside a properties hashtable
      * @param props properties object to resolve
      */
     private void resolveAllProperties(Properties props) throws BuildException {
         for (Enumeration e = props.keys(); e.hasMoreElements();) {
             String name = (String) e.nextElement();
             String value = props.getProperty(name);

             boolean resolved = false;
             while (!resolved) {
                 Vector fragments = new Vector();
                 Vector propertyRefs = new Vector();
                 ProjectHelper.parsePropertyString(value, fragments,
                                                   propertyRefs);

                 resolved = true;
                 if (propertyRefs.size() != 0) {
                     StringBuffer sb = new StringBuffer();
                     Enumeration i = fragments.elements();
                     Enumeration j = propertyRefs.elements();
                     while (i.hasMoreElements()) {
                         String fragment = (String) i.nextElement();
                         if (fragment == null) {
                             String propertyName = (String) j.nextElement();
                             if (propertyName.equals(name)) {
                                 throw new BuildException("Property " + name
                                                          + " was circularly "
                                                          + "defined.");
                             }
                             fragment = getProject().getProperty(propertyName);
                             if (fragment == null) {
                                 if (props.containsKey(propertyName)) {
                                     fragment = props.getProperty(propertyName);
                                     resolved = false;
                                 } else {
                                     fragment = "${" + propertyName + "}";
                                 }
                             }
                         }
                         sb.append(fragment);
                     }
                     value = sb.toString();
                     props.put(name, value);
                 }
             }
         }
     }
 }
	/*
	* 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.taskdefs;

	import org.apache.tools.ant.Task;
	import org.apache.tools.ant.BuildException;
	import org.apache.tools.ant.Project;
	import org.apache.tools.ant.AntClassLoader;
	import org.apache.tools.ant.ProjectHelper;
	import org.apache.tools.ant.types.Path;
	import org.apache.tools.ant.types.Reference;
	import java.io.File;
	import java.io.FileInputStream;
	import java.io.IOException;
	import java.io.InputStream;
	import java.util.Properties;
	import java.util.Vector;
	import java.util.Enumeration;

	/**
	* Sets a property by name, or set of properties (from file or
	* resource) in the project. </p>
	* Properties are immutable: whoever sets a property first freezes it for the
	* rest of the build; they are most definately not variable.
	* <p>There are five ways to set properties:</p>
	* <ul>
	* <li>By supplying both the <i>name</i> and <i>value</i> attribute.</li>
	* <li>By supplying both the <i>name</i> and <i>refid</i> attribute.</li>
	* <li>By setting the <i>file</i> attribute with the filename of the property
	* file to load. This property file has the format as defined by the file used
	* in the class java.util.Properties.</li>
	* <li>By setting the <i>resource</i> attribute with the resource name of the
	* property file to load. This property file has the format as defined by the
	* file used in the class java.util.Properties.</li>
	* <li>By setting the <i>environment</i> attribute with a prefix to use.
	* Properties will be defined for every environment variable by
	* prefixing the supplied name and a period to the name of the variable.</li>
	* </ul>
	* <p>Although combinations of these ways are possible, only one should be used
	* at a time. Problems might occur with the order in which properties are set, for
	* instance.</p>
	* <p>The value part of the properties being set, might contain references to other
	* properties. These references are resolved at the time these properties are set.
	* This also holds for properties loaded from a property file.</p>
	* Properties are case sensitive.
	*
	* @author costin@dnt.ro
	* @author <a href="mailto:rubys@us.ibm.com">Sam Ruby</a>
	* @author <a href="mailto:glennm@ca.ibm.com">Glenn McAllister</a>
	* @since Ant 1.1
	*/
	public class Property extends Task {

	protected String name;
	protected String value;
	protected File file;
	protected String resource;
	protected Path classpath;
	protected String env;
	protected Reference ref;
	protected String prefix;
	private Project fallback;

	protected boolean userProperty; // set read-only properties

	public Property() {
	this(false);
	}

	/**
	* @since Ant 1.5
	*/
	protected Property(boolean userProperty) {
	this(userProperty, null);
	}

	/**
	* @since Ant 1.5
	*/
	protected Property(boolean userProperty, Project fallback) {
	this.userProperty = userProperty;
	this.fallback = fallback;
	}

	/**
	* sets the name of the property to set.
	* @param name property name
	*/
	public void setName(String name) {
	this.name = name;
	}

	public String getName() {
	return name;
	}

	/**
	* Sets the property to the absolute filename of the
	* given file. If the value of this attribute is an absolute path, it
	* is left unchanged (with / and \ characters converted to the
	* current platforms conventions). Otherwise it is taken as a path
	* relative to the project's basedir and expanded.
	* @param location path to set
	*/
	public void setLocation(File location) {
	setValue(location.getAbsolutePath());
	}

	/**
	* Sets the value of the property.
	* @param value value to assign
	*/

	public void setValue(String value) {
	this.value = value;
	}


	public String getValue() {
	return value;
	}

	/**
	* the filename of a property file to load.
	*@param file filename
	*/
	public void setFile(File file) {
	this.file = file;
	}

	public File getFile() {
	return file;
	}

	/**
	* Prefix to apply to properties loaded using <code>file</code>
	* or <code>resource</code>.
	* A "." is appended to the prefix if not specified.
	* @param prefix prefix string
	* @since Ant 1.5
	*/
	public void setPrefix(String prefix) {
	this.prefix = prefix;
	if (!prefix.endsWith(".")) {
	this.prefix += ".";
	}
	}

	/**
	* @since Ant 1.5
	*/
	public String getPrefix() {
	return prefix;
	}

	/**
	* Sets a reference to an Ant datatype
	* declared elsewhere.
	* Only yields reasonable results for references
	* PATH like structures or properties.
	* @param ref reference
	*/
	public void setRefid(Reference ref) {
	this.ref = ref;
	}

	public Reference getRefid() {
	return ref;
	}

	/**
	* the resource name of a property file to load
	* @param resource resource on classpath
	*/
	public void setResource(String resource) {
	this.resource = resource;
	}

	public String getResource() {
	return resource;
	}

	/**
	* the prefix to use when retrieving environment variables.
	* Thus if you specify environment="myenv"
	* you will be able to access OS-specific
	* environment variables via property names "myenv.PATH" or
	* "myenv.TERM".
	* <p>
	* Note that if you supply a property name with a final
	* "." it will not be doubled. ie environment="myenv." will still
	* allow access of environment variables through "myenv.PATH" and
	* "myenv.TERM". This functionality is currently only implemented
	* on select platforms. Feel free to send patches to increase the number of platforms
	* this functionality is supported on ;).<br>
	* Note also that properties are case sensitive, even if the
	* environment variables on your operating system are not, e.g. it
	* will be ${env.Path} not ${env.PATH} on Windows 2000.
	* @param env prefix
	*/

	public void setEnvironment(String env) {
	this.env = env;
	}

	/**
	* @since Ant 1.5
	*/
	public String getEnvironment() {
	return env;
	}


	/**
	* The classpath to use when looking up a resource.
	* @param classpath to add to any existing classpath
	*/

	public void setClasspath(Path classpath) {
	if (this.classpath == null) {
	this.classpath = classpath;
	} else {
	this.classpath.append(classpath);
	}
	}

	/**
	* The classpath to use when looking up a resource.
	*/
	public Path createClasspath() {
	if (this.classpath == null) {
	this.classpath = new Path(project);
	}
	return this.classpath.createPath();
	}

	/**
	* the classpath to use when lookingup a resource,
	* given as reference to a <path> defined elsewhere
	public void setClasspathRef(Reference r) {
	createClasspath().setRefid(r);
	}

	/**
	* @since Ant 1.5
	*/
	public Path getClasspath() {
	return classpath;
	}

	/**
	* @deprecated This was never a supported feature and has been
	* deprecated without replacement
	* @ant.setter skip="true"
	*/
	public void setUserProperty(boolean userProperty) {
	log("DEPRECATED: Ignoring request to set user property in Property"
	+ " task.", Project.MSG_WARN);
	}

	/**
	* get the value of this property
	* @return the current value or the empty string
	*/
	public String toString() {
	return value == null ? "" : value;
	}

	/**
	* set the property in the project to the value.
	* if the task was give a file, resource or env attribute
	* here is where it is loaded
	*/
	public void execute() throws BuildException {
	if (name != null) {
	if (value == null && ref == null) {
	throw new BuildException("You must specify value, location or "
	+ "refid with the name attribute",
	location);
	}
	} else {
	if (file == null && resource == null && env == null) {
	throw new BuildException("You must specify file, resource or "
	+ "environment when not using the "
	+ "name attribute", location);
	}
	}

	if (file == null && resource == null && prefix != null) {
	throw new BuildException("Prefix is only valid when loading from "
	+ "a file or resource", location);
	}

	if ((name != null) && (value != null)) {
	addProperty(name, value);
	}

	if (file != null) {
	loadFile(file);
	}

	if (resource != null) {
	loadResource(resource);
	}

	if (env != null) {
	loadEnvironment(env);
	}

	if ((name != null) && (ref != null)) {
	try {
	addProperty(name,
	ref.getReferencedObject(getProject()).toString());
	} catch (BuildException be) {
	if (fallback != null) {
	addProperty(name,
	ref.getReferencedObject(fallback).toString());
	} else {
	throw be;
	}
	}
	}
	}

	/**
	* load properties from a file
	* @param file file to load
	*/
	protected void loadFile(File file) throws BuildException {
	Properties props = new Properties();
	log("Loading " + file.getAbsolutePath(), Project.MSG_VERBOSE);
	try {
	if (file.exists()) {
	FileInputStream fis = new FileInputStream(file);
	try {
	props.load(fis);
	} finally {
	if (fis != null) {
	fis.close();
	}
	}
	addProperties(props);
	} else {
	log("Unable to find property file: " + file.getAbsolutePath(),
	Project.MSG_VERBOSE);
	}
	} catch (IOException ex) {
	throw new BuildException(ex, location);
	}
	}

	/**
	* load properties from a resource in the current classpath
	* @param name name of resource to load
	*/
	protected void loadResource(String name) {
	Properties props = new Properties();
	log("Resource Loading " + name, Project.MSG_VERBOSE);
	InputStream is = null;
	try {
	ClassLoader cL = null;

	if (classpath != null) {
	cL = new AntClassLoader(project, classpath);
	} else {
	cL = this.getClass().getClassLoader();
	}

	if (cL == null) {
	is = ClassLoader.getSystemResourceAsStream(name);
	} else {
	is = cL.getResourceAsStream(name);
	}

	if (is != null) {
	props.load(is);
	addProperties(props);
	} else {
	log("Unable to find resource " + name, Project.MSG_WARN);
	}
	} catch (IOException ex) {
	throw new BuildException(ex, location);
	} finally {
	if (is != null) {
	try {
	is.close();
	} catch (IOException e) {}
	}
	}

	}

	/**
	* load the environment values
	* @param prefix prefix to place before them
	*/
	protected void loadEnvironment(String prefix) {
	Properties props = new Properties();
	if (!prefix.endsWith(".")) {
	prefix += ".";
	}
	log("Loading Environment " + prefix, Project.MSG_VERBOSE);
	Vector osEnv = Execute.getProcEnvironment();
	for (Enumeration e = osEnv.elements(); e.hasMoreElements();) {
	String entry = (String) e.nextElement();
	int pos = entry.indexOf('=');
	if (pos == -1) {
	log("Ignoring: " + entry, Project.MSG_WARN);
	} else {
	props.put(prefix + entry.substring(0, pos),
	entry.substring(pos + 1));
	}
	}
	addProperties(props);
	}

	/**
	* iterate through a set of properties,
	* resolve them then assign them
	*/
	protected void addProperties(Properties props) {
	resolveAllProperties(props);
	Enumeration e = props.keys();
	while (e.hasMoreElements()) {
	String name = (String) e.nextElement();
	String value = props.getProperty(name);

	String v = project.replaceProperties(value);

	if (prefix != null) {
	name = prefix + name;
	}

	addProperty(name, v);
	}
	}

	/**
	* add a name value pair to the project property set
	* @param n name of property
	* @param v value to set
	*/
	protected void addProperty(String n, String v) {
	if (userProperty) {
	if (project.getUserProperty(n) == null) {
	project.setInheritedProperty(n, v);
	} else {
	log("Override ignored for " + n, Project.MSG_VERBOSE);
	}
	} else {
	project.setNewProperty(n, v);
	}
	}

	/**
	* resolve properties inside a properties hashtable
	* @param props properties object to resolve
	*/
	private void resolveAllProperties(Properties props) throws BuildException {
	for (Enumeration e = props.keys(); e.hasMoreElements();) {
	String name = (String) e.nextElement();
	String value = props.getProperty(name);

	boolean resolved = false;
	while (!resolved) {
	Vector fragments = new Vector();
	Vector propertyRefs = new Vector();
	ProjectHelper.parsePropertyString(value, fragments,
	propertyRefs);

	resolved = true;
	if (propertyRefs.size() != 0) {
	StringBuffer sb = new StringBuffer();
	Enumeration i = fragments.elements();
	Enumeration j = propertyRefs.elements();
	while (i.hasMoreElements()) {
	String fragment = (String) i.nextElement();
	if (fragment == null) {
	String propertyName = (String) j.nextElement();
	if (propertyName.equals(name)) {
	throw new BuildException("Property " + name
	+ " was circularly "
	+ "defined.");
	}
	fragment = getProject().getProperty(propertyName);
	if (fragment == null) {
	if (props.containsKey(propertyName)) {
	fragment = props.getProperty(propertyName);
	resolved = false;
	} else {
	fragment = "${" + propertyName + "}";
	}
	}
	}
	sb.append(fragment);
	}
	value = sb.toString();
	props.put(name, value);
	}
	}
	}
	}
	}