private boolean failOnError = true;

	private boolean showProblems = true;

	private String errorProperty;

			IResource rootResource;

				rootResource = ResourcesPlugin.getWorkspace().getRoot();

				rootResource = targetProject;

			Problems problems = new Problems(rootResource);

			if (showProblems) {

				showProblems(problems);

			}

			if (errorProperty != null) {

				if (problems.getErrors().length > 0) {

					getProject().setProperty(errorProperty, "true"); //$NON-NLS-1$

				}

			}

			if (failOnError) {

				if (problems.getErrors().length > 0) {

					throw new BuildException();

				}

			}

	private void showProblems(Problems problems) throws CoreException {

		IMarker[] warningsAndErrors = problems.getWarningAndErrors();

		for (int i=0; i<warningsAndErrors.length; ++i) {

			IMarker problem = warningsAndErrors[i];

			int severity = ((Integer) problem.getAttribute(IMarker.SEVERITY)).intValue();

			int logLevel = (severity == IMarker.SEVERITY_ERROR) ? Project.MSG_WARN : Project.MSG_ERR;

			getProject().log(formatProblemMessage(problem), logLevel);

		}

	}

	/**

	 * Returns a string suitable for display that represents a build problem.

	 * 

	 * @param problem the problem

	 * @return a string suitable for display that represents the problem

	 */

	private String formatProblemMessage(IMarker problem) {

		StringBuffer sb = new StringBuffer();

		// start with "path:linenum: "

		IResource resource = problem.getResource();

		if (resource != null) {

			IPath resourceLocation = resource.getLocation();

			if (resourceLocation != null) {

				sb.append(resourceLocation.toOSString());

				sb.append(':');

				int lineNumber = problem.getAttribute(IMarker.LINE_NUMBER, -1);

				if (lineNumber != -1) {

					sb.append(lineNumber);

					sb.append(':');

				}

				sb.append(' ');

			}

		}

		// if it is a warning, append "warning: "

		int severity = problem.getAttribute(IMarker.SEVERITY, -1);

		if (severity == IMarker.SEVERITY_WARNING) {

			sb.append("warning: "); //$NON-NLS-1$

		}

		// append the problem's actual message

		String message = problem.getAttribute(IMarker.MESSAGE, null);

		if (message != null) {

			sb.append(message);

		}

		return sb.toString();

	}

	/**

	 * Sets whether build errors will cause the build to fail; defaults to <code>true</code>.

	 *

	 * @param value whether build errors should cause the build to fail

	 */

	public void setFailOnError(boolean value) {

		failOnError = value;

	}

	/**

	 * Sets whether build errors and warnings should be displayed; defaults to <code>true</code>.

	 *

	 * @param value whether build errors and warnings should be displayed

	 */

	public void setShowProblems(boolean value) {

		showProblems = value;

	}

	/**

	 * The property to set (to the value "true") if the build fails.

	 * 

	 * @param value the name of the Ant property

	 */

	public void setErrorProperty(String value) {

		errorProperty = value;

	}

	/**

	 * Helper class to keep track of build problems.

	 */

	private static class Problems {

		private final IResource resource;

		private IMarker[] allProblems;

		private IMarker[] errors;

		private IMarker[] errorsAndWarnings;

		public Problems(IResource resource) {

			this.resource = resource;

		}

		/**

		 * Returns all problem markers on the resource.

		 * @throws CoreException

		 */

		public IMarker[] getAllProblems() throws CoreException {

			if (allProblems == null) {

				allProblems = resource.findMarkers(IMarker.PROBLEM, true, IResource.DEPTH_INFINITE);

			}

			return allProblems;

		}

		/**

		 * Returns all problem markers on the resource whose severity is <code>IMarker.SEVERITY_ERROR</code>.

		 * @throws CoreException

		 */

		public IMarker[] getErrors() throws CoreException {

			if (errors == null) {

				errors = filterProblems(getAllProblems(), IMarker.SEVERITY_ERROR);

			}

			return errors;

		}

		/**

		 * Returns all problem markers on the resource whose severity is <code>IMarker.SEVERITY_ERROR</code>

		 * or <code>IMarker.SEVERITY_WARNING</code>.

		 * @throws CoreException

		 */

		public IMarker[] getWarningAndErrors() throws CoreException {

			if (errorsAndWarnings == null) {

				errorsAndWarnings = filterProblems(getAllProblems(), IMarker.SEVERITY_WARNING);

			}

			return errorsAndWarnings;

		}

		/**

		 * Returns only those markers whose severity is equal to or greater than

		 * the specified value.

		 * 

		 * @param minimumSeverity the desired minimum severity

		 * @return an array that contains only those markers whose severity is

		 * greater than or equal to <code>minimumSeverity</code>

		 * @throws CoreException

		 */

		private static IMarker[] filterProblems(IMarker[] problems, int minimumSeverity) throws CoreException {

			List filteredProblems = new ArrayList(problems.length);

			for (int i = 0; i < problems.length; ++i) {

				Integer severity = (Integer) problems[i].getAttribute(IMarker.SEVERITY);

				if (severity != null) {

					if (severity.intValue() >= minimumSeverity) {

						filteredProblems.add(problems[i]);

					}

				}

			}

			return (IMarker[]) filteredProblems.toArray(new IMarker[filteredProblems.size()]);

		}

	}