Index: src/main/org/apache/tools/ant/helper/ProjectHelper2.java
===================================================================
--- src/main/org/apache/tools/ant/helper/ProjectHelper2.java	(revision 1132928)
+++ src/main/org/apache/tools/ant/helper/ProjectHelper2.java	(working copy)
@@ -27,6 +27,7 @@
 import org.apache.tools.ant.Target;
 import org.apache.tools.ant.Task;
 import org.apache.tools.ant.UnknownElement;
+import org.apache.tools.ant.DebugTask;
 import org.apache.tools.ant.types.Resource;
 import org.apache.tools.ant.types.resources.FileProvider;
 import org.apache.tools.ant.types.resources.URLProvider;
@@ -923,7 +924,11 @@
             target.setProject(project);
             target.setLocation(new Location(context.getLocator()));
             context.addTarget(target);
-
+            boolean isTarget = false;
+            if(!(target instanceof ExtensionPoint)) {
+            	isTarget = true;
+            }
+            
             for (int i = 0; i < attrs.getLength(); i++) {
                 String attrUri = attrs.getURI(i);
                 if (attrUri != null && !attrUri.equals("") && !attrUri.equals(uri)) {
@@ -1015,6 +1020,18 @@
                     }
                 }
             }
+
+        	if(isTarget && name.equals(project.getBreakAt())) {
+        		// If the current element is a target and it is the same one as specified
+        		// for Ant to suspend execution at, then add an internal dependency on
+        		// the Debug Target
+        		DebugTask.createDebugTarget(project);
+        		
+        		// add this dependency to the end of the dependency list so that this target 
+        		// executes immediately ahead of the -breakAt target
+        		target.addDependency(DebugTask.DEBUG_TARGET_NAME);
+        	}
+
             if (!isInIncludeMode && context.isIgnoringProjectTag()
                 && (prefix = getTargetPrefix(context)) != null) {
                 // In an imported file (and not completely
Index: src/main/org/apache/tools/ant/Project.java
===================================================================
--- src/main/org/apache/tools/ant/Project.java	(revision 1132928)
+++ src/main/org/apache/tools/ant/Project.java	(working copy)
@@ -210,6 +210,19 @@
     private boolean keepGoingMode = false;
 
     /**
+     * Contains the target to break the execution at.
+     */
+	protected String breakAt;
+	
+	public void setBreakAt(String breakAt) {
+		this.breakAt = breakAt;
+	}
+	
+	public String getBreakAt() {
+		return breakAt;
+	}
+	
+    /**
      * Set the input handler.
      *
      * @param handler the InputHandler instance to use for gathering input.
Index: src/main/org/apache/tools/ant/DebugTask.java
===================================================================
--- src/main/org/apache/tools/ant/DebugTask.java	(revision 0)
+++ src/main/org/apache/tools/ant/DebugTask.java	(revision 0)
@@ -0,0 +1,329 @@
+package org.apache.tools.ant;
+
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import org.apache.tools.ant.BuildException;
+import org.apache.tools.ant.ComponentHelper;
+import org.apache.tools.ant.Project;
+import org.apache.tools.ant.Target;
+import org.apache.tools.ant.Task;
+import org.apache.tools.ant.input.DefaultInputHandler;
+import org.apache.tools.ant.input.InputHandler;
+import org.apache.tools.ant.input.InputRequest;
+import org.apache.tools.ant.taskdefs.PathConvert;
+import org.apache.tools.ant.taskdefs.Property;
+import org.apache.tools.ant.types.Path;
+import org.apache.tools.ant.types.Reference;
+import org.apache.tools.ant.types.ResourceCollection;
+import org.apache.tools.ant.util.StringUtils;
+
+/**
+ * A stand alone debug task that plugs into the build through projecthelper
+ * class by injecting a dependency at the end of a target. This is a POC and
+ * does not yet work for Extension-Points.
+ */
+public class DebugTask extends Task {
+	/**
+	 * Debugger prompt
+	 */
+	public static final String PROMPT = "DEBUGGER> ";
+
+	/**
+	 * Standard target name for the internal debugger
+	 */
+	public static final String DEBUG_TARGET_NAME = "-internal-debugger";
+
+	/*
+	 * A static final debug target that is injected as a dependency. We may need
+	 * to have more than one such target if we are to allow multiple
+	 * break-points in the build.
+	 */
+	private static final Target debugTarget = new Target();
+
+	/*
+	 * Set of all commands that can be interpreted at runtime.
+	 */
+	private static Set supportedCommands = new HashSet();
+
+	static {
+		// add any more commands to be supported here
+		// if need be, this can be considered to be
+		// moved to a separate properties file
+		supportedCommands.add("locate");
+		supportedCommands.add("inspect");
+		supportedCommands.add("return");
+	}
+
+	public void execute() throws BuildException {
+		// expect input here
+		InputRequest ir = new InputRequest(PROMPT);
+		InputHandler ih = new DefaultInputHandler();
+		String command = null;
+		getProject().log(
+				StringUtils.LINE_SEP
+						+ "-------- Ant Command Line Debugger --------"
+						+ StringUtils.LINE_SEP + StringUtils.LINE_SEP);
+
+		// keep accepting inputs, until the user enters the return command
+		do {
+			ih.handleInput(ir);
+			command = ir.getInput();
+			handleCommand(command);
+			getProject().log(""); // log a new line
+		} while (!"return".equals(command));
+
+		// resume build execution on this
+		getProject().log(
+				StringUtils.LINE_SEP
+						+ "--------- Resuming Ant Execution ----------"
+						+ StringUtils.LINE_SEP);
+	}
+
+	/**
+	 * Static method to create a runtime-debug target. For purposes of Command
+	 * Line Debugger (CLD), the target returned by this method, and identified
+	 * by DEBUG_TARGET_NAME must be added at the end of the dependency list of
+	 * the target where the break point exists.
+	 * 
+	 * @param project
+	 * @return
+	 */
+	public static Target createDebugTarget(Project project) {
+		// see what is the best value for the Location to assume?
+		// Location loc = new Location(??);
+
+		debugTarget.setProject(project);
+		debugTarget.setName(DEBUG_TARGET_NAME);
+		project.addTarget(debugTarget);
+		// create an instance of debug task and attach it to this project
+		Task debugtask = project.createTask("debug");
+		debugtask.setProject(project);
+		debugtask.setTaskName("Debugger");
+		debugTarget.addTask(debugtask);
+		return debugTarget;
+	}
+
+	/*
+	 * Interprets user input and decides if the command is supported or should
+	 * be rejected.
+	 */
+	protected void handleCommand(String command) {
+		if (command == null || command.trim().length() == 0) {
+			getProject().log("Invalid command. Use /? for more information.");
+		}
+		command = command.trim();
+		if (command.equals("/?")) {
+			printUsage();
+			return;
+		}
+
+		String[] tokens = command.split(" ");
+		if (!supportedCommands.contains(tokens[0])) {
+			printUsage();
+			return;
+		}
+
+		DebugSupport[] debuggers = new DebugSupport[] { new NoOp(),
+				new Inspector(), new Locator() };
+		DebugSupport selected = null;
+		for (int j = 0; j < debuggers.length; j++) {
+			if (debuggers[j].commandSupported(tokens[0]))
+				selected = debuggers[j];
+		}
+		selected.execute(getProject(), tokens);
+	}
+
+	protected void printUsage() {
+		// log all help stuff here
+		getProject()
+				.log(
+						"You may use one of the following commands: locate, inspect, return");
+		getProject()
+				.log(
+						"Type the command followed by /? for more information. Eg. inspect /?");
+	}
+
+	protected static List searchTask(Class expectedTaskClass, Project project) {
+		List result = new ArrayList();
+		for (Iterator iterator = project.getTargets().values().iterator(); iterator
+				.hasNext();) {
+			Target t = (Target) iterator.next();
+			for (int i = 0; i < t.getTasks().length; i++) {
+				Task task = t.getTasks()[i];
+				Class taskClass = ComponentHelper.getComponentHelper(project)
+						.getComponentClass(task.getTaskType());
+				// will need to see in what cases it could return a null type
+				// perhaps failing when the task is using a custom antlib
+				// defined task
+				if (taskClass != null && taskClass.equals(expectedTaskClass)) {
+					result.add(task);
+				}
+			}
+		}
+		return result;
+	}
+
+	/**
+	 * An interface for supporting debug commands.
+	 */
+	public static interface DebugSupport {
+
+		/**
+		 * Check if this command is supported.
+		 * 
+		 * @param command
+		 * @return
+		 */
+		public boolean commandSupported(String command);
+
+		/**
+		 * Main execution body of the class. Pass all command parameters.
+		 * 
+		 * @param project
+		 * @param params
+		 */
+		public void execute(Project project, String[] params);
+
+		/**
+		 * Prints usage of the command.
+		 * 
+		 * @param project
+		 */
+		public void printUsage(Project project);
+
+	}
+
+	/**
+	 * Used to implement commands that should not be handled by
+	 * {@link DebugSupport} at all. Example, the 'return' command
+	 */
+	public static final class NoOp implements DebugSupport {
+
+		public boolean commandSupported(String command) {
+			return "return".equalsIgnoreCase(command);
+		}
+
+		public void execute(Project project, String[] params) {
+			// do nothing
+		}
+
+		public void printUsage(Project project) {
+		};
+	}
+
+	/**
+	 * Locates properties / paths in static build sources
+	 */
+	public static final class Locator implements DebugSupport {
+
+		public boolean commandSupported(String command) {
+			return "locate".equalsIgnoreCase(command);
+		}
+
+		public void execute(Project project, String[] params) {
+			// the command syntax is 'locate property some.property'
+			// or 'locate path some.path
+			if (params.length != 3 || "/?".equals(params[1])) {
+				printUsage(project);
+				return;
+			}
+
+			List matches = null;
+			String key = null;
+			if ("property".equalsIgnoreCase(params[1])) {
+				// locate and publish the property
+				matches = DebugTask.searchTask(Property.class, project);
+				key = "name";
+			} else if ("path".equalsIgnoreCase(params[1])) {
+				// locate and publish the path
+				matches = DebugTask.searchTask(Path.class, project);
+				key = "id";
+			} else {
+				// see if any other component may be supported
+				project.log("Unexpected component: " + params[1]);
+				project.log("Supported components are property, path.");
+				return;
+			}
+
+			// probably accept some kind of a query from end user and select the
+			// target object based on the query
+			for (Iterator iterator = matches.iterator(); iterator.hasNext();) {
+				Task task = (Task) iterator.next();
+				// display attributes
+				Map attributeMap = task.getWrapper().getAttributeMap();
+				if (!params[2].equals(attributeMap.get(key))) {
+					continue;
+				}
+				String value = (String) attributeMap.get("value");
+				project.log("Detected a property by name [" + params[2]
+						+ "]. Build file value: " + value);
+				// and their respected location
+				project.log("Located at: " + task.getLocation().toString());
+			}
+		}
+
+		public void printUsage(Project project) {
+			project.log("Incorrect Parameters");
+			project.log("Usage: locate property/path propertyname/pathname");
+		}
+	}
+
+	/**
+	 * Inspects the current value of a property, path or some reference.
+	 */
+	public static final class Inspector implements DebugSupport {
+
+		public boolean commandSupported(String command) {
+			return "inspect".equalsIgnoreCase(command);
+		}
+
+		public void execute(Project project, String[] params) {
+			if (params.length < 3 || "/?".equals(params[1])) {
+				printUsage(project);
+			}
+
+			if ("property".equalsIgnoreCase(params[1])) {
+				// show all matches for a property
+				Object value = PropertyHelper.getProperty(project, params[2]);
+				if (value != null) {
+					project.log("Detected a property by name [" + params[1]
+							+ "]. Current value: " + value);
+				} else {
+					project.log("Found no such property.");
+				}
+			} else if ("path".equalsIgnoreCase(params[1])) {
+				// look optional component
+				// the remaining part of the string could be:
+				// id=<someid> or refid=<somerefid>
+				Object ref = project.getReference(params[2]);
+				if (ref instanceof ResourceCollection) {
+					if (ref != null) {
+						PathConvert path = (PathConvert) project
+								.createTask("pathconvert");
+						path.setProject(project);
+						path.setPathSep(StringUtils.LINE_SEP + "    - ");
+						path.add((ResourceCollection) ref);
+						path.execute();
+					} else {
+						project.log("No path-reference found for " + params[2]);
+					}
+				} else {
+					project.log("No path found for reference id: " + params[2]);
+				}
+			}
+
+		}
+
+		public void printUsage(Project project) {
+			project.log("Incorrect Parameters");
+			project.log("Usage: inspect property some.property");
+			project.log("       inspect path path.id");
+		}
+	}
+}

Property changes on: src\main\org\apache\tools\ant\DebugTask.java
___________________________________________________________________
Added: svn:eol-style
   + native

Index: src/main/org/apache/tools/ant/taskdefs/defaults.properties
===================================================================
--- src/main/org/apache/tools/ant/taskdefs/defaults.properties	(revision 1132928)
+++ src/main/org/apache/tools/ant/taskdefs/defaults.properties	(working copy)
@@ -230,3 +230,4 @@
 renameext=org.apache.tools.ant.taskdefs.optional.RenameExtensions
 starteam=org.apache.tools.ant.taskdefs.optional.scm.AntStarTeamCheckOut
 style=org.apache.tools.ant.taskdefs.XSLTProcess
+debug=org.apache.tools.ant.DebugTask
Index: src/main/org/apache/tools/ant/Main.java
===================================================================
--- src/main/org/apache/tools/ant/Main.java	(revision 1132928)
+++ src/main/org/apache/tools/ant/Main.java	(working copy)
@@ -149,6 +149,11 @@
     private boolean proxy = false;
 
     /**
+     * Target at which to break execution sequence
+     */
+    private String breakAt = null;
+    
+    /**
      * Prints the message of the Throwable if it (the message) is not
      * <code>null</code>.
      *
@@ -382,6 +387,8 @@
                 throw new BuildException(msg);
             } else if (arg.equals("-autoproxy")) {
                 proxy = true;
+            } else if (arg.equals("-breakAt")) {
+            	breakAt = args[++i];
             } else if (arg.startsWith("-")) {
                 // we don't have any more args to recognize!
                 String msg = "Unknown argument: " + arg;
@@ -761,7 +768,7 @@
 
 
                 project.init();
-
+                project.setBreakAt(breakAt);
                 // resolve properties
                 PropertyHelper propertyHelper
                     = (PropertyHelper) PropertyHelper.getPropertyHelper(project);