MirahBuilder.java

package org.mirah.core.builder;

import java.io.File;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IMarker;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IResourceDelta;
import org.eclipse.core.resources.IResourceDeltaVisitor;
import org.eclipse.core.resources.IResourceVisitor;
import org.eclipse.core.resources.IncrementalProjectBuilder;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.jdt.core.IClasspathEntry;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.core.JavaCore;
import org.eclipse.jdt.core.JavaModelException;
import org.mirah.MirahCommand;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.helpers.DefaultHandler;

public class MirahBuilder extends IncrementalProjectBuilder {

	class SampleDeltaVisitor implements IResourceDeltaVisitor {
		private Set<IResource> resources;

		public SampleDeltaVisitor(Set<IResource> resources) {
			this.resources = resources;
		}
		
		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.core.resources.IResourceDeltaVisitor#visit(org.eclipse.core.resources.IResourceDelta)
		 */
		public boolean visit(IResourceDelta delta) throws CoreException {
			IResource resource = delta.getResource();
			if (resource instanceof IFile && resource.getName().endsWith(".mirah")) {
			switch (delta.getKind()) {
			case IResourceDelta.ADDED:
				// handle added resource
				resources.add(resource);
				break;
			case IResourceDelta.REMOVED:
				// handle removed resource
				break;
			case IResourceDelta.CHANGED:
				// handle changed resource
				resources.add(resource);
				break;
			}
			}
			//return true to continue visiting children.
			return true;
		}
	}

	class SampleResourceVisitor implements IResourceVisitor {
		private Set<IResource> resources;

		public SampleResourceVisitor(Set<IResource> resources) {
			this.resources = resources;
		}

		public boolean visit(IResource resource) {
			resources.add(resource);
			//return true to continue visiting children.
			return true;
		}
	}

	class ClasspathBuilder {
		private StringBuffer classpath = new StringBuffer();
		private Set<String> visitedFiles = new HashSet<String>();
		private Set<IJavaProject> visitedProjects = new HashSet<IJavaProject>();
		private IJavaProject project;

		public ClasspathBuilder(IJavaProject project) {
			this.project = project;
		}

		public String buildClasspath() {
			if (visitedProjects.size() == 0) {
				visitProject(project);
			}
			return classpath.toString();
		}
		
		private void visitProject(IJavaProject project) {
			boolean first = visitedProjects.size() == 0;
			if (visitedProjects.contains(project)) {
				return;
			}
			visitedProjects.add(project);
			try {
				visitPath(project.getOutputLocation());
				for (IClasspathEntry entry : project.getResolvedClasspath(true)) {
					switch (entry.getEntryKind()) {
					case IClasspathEntry.CPE_LIBRARY:
						visitPath(entry.getPath());
						break;
					case IClasspathEntry.CPE_PROJECT:
						if (first || entry.isExported()) {
							visitProject(getJavaProject(entry));
						}
						break;
					case IClasspathEntry.CPE_SOURCE:
						visitPath(entry.getOutputLocation());
					}
				}
			} catch (JavaModelException e) {
				e.printStackTrace();
				return;
			}
		}

		private IJavaProject getJavaProject(IClasspathEntry entry) {
			IProject project = ResourcesPlugin.getWorkspace().getRoot().getProject(entry.getPath().segment(0));
			if (project == null) {
				return null;
			} else {
				return JavaCore.create(project);
			}
		}

		private void visitPath(IPath path) {
			if (path == null) {
				return;
			}
			String filename = getLocation(path);
			if (filename == null) {
				return;
			}
			if (visitedFiles.contains(filename)) {
				return;
			}
			visitedFiles.add(filename);
			if (classpath.length() > 0) {
				classpath.append(File.pathSeparator);
			}
			classpath.append(filename);
		}
	}
	
	public static final String BUILDER_ID = "org.mirah.core.mirahBuilder";

	private static final String MARKER_TYPE = "org.mirah.core.mirahProblem";

	private void addMarker(IFile file, String message, int lineNumber,
			int severity) {
		try {
			IMarker marker = file.createMarker(MARKER_TYPE);
			marker.setAttribute(IMarker.MESSAGE, message);
			marker.setAttribute(IMarker.SEVERITY, severity);
			if (lineNumber == -1) {
				lineNumber = 1;
			}
			marker.setAttribute(IMarker.LINE_NUMBER, lineNumber);
		} catch (CoreException e) {
		}
	}

	public void compileResources(Set<IResource> resources) throws JavaModelException {
		ArrayList<String> args = new ArrayList<String>();
		IJavaProject project = JavaCore.create(getProject());
		String classpath = new ClasspathBuilder(project).buildClasspath();
		args.add("--classpath");
		args.add(classpath);
		args.add("-d");
		args.add(getLocation(project.getOutputLocation()));
		int files = 0;
		IFile file = null;
		for (IResource resource : resources) {
			if (resource instanceof IFile && resource.getName().endsWith(".mirah")) {
				file = (IFile) resource;
				deleteMarkers(file);
				args.add(file.getLocation().toOSString());
				files += 1;
			}
		}
		if (files > 0) {
			try {
				MirahCommand.compile(args);
			} catch (Exception ex) {
				addMarker(file, ex.getLocalizedMessage(), -1, IMarker.SEVERITY_ERROR);
			}
		}
	}				

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.internal.events.InternalBuilder#build(int,
	 *      java.util.Map, org.eclipse.core.runtime.IProgressMonitor)
	 */
	protected IProject[] build(int kind, Map args, IProgressMonitor monitor)
			throws CoreException {
		if (kind == FULL_BUILD) {
			fullBuild(monitor);
		} else {
			IResourceDelta delta = getDelta(getProject());
			if (delta == null) {
				fullBuild(monitor);
			} else {
				incrementalBuild(delta, monitor);
			}
		}
		return null;
	}

	private void deleteMarkers(IFile file) {
		try {
			file.deleteMarkers(MARKER_TYPE, false, IResource.DEPTH_ZERO);
		} catch (CoreException ce) {
		}
	}

	protected void fullBuild(final IProgressMonitor monitor)
			throws CoreException {
		try {
			Set<IResource> resources = new HashSet<IResource>();
			getProject().accept(new SampleResourceVisitor(resources));
			compileResources(resources);
		} catch (CoreException e) {
		}
	}

	protected void incrementalBuild(IResourceDelta delta,
			IProgressMonitor monitor) throws CoreException {
		Set<IResource> resources = new HashSet<IResource>();
		delta.accept(new SampleDeltaVisitor(resources));
		compileResources(resources);
	}
	
	private String getLocation(IPath path) {
		if (path.toFile().canRead()) {
			return path.toOSString();
		}
		IResource resource = ResourcesPlugin.getWorkspace().getRoot().findMember(path);
		if (resource == null) {
			System.err.println("Can't find resource " + path);
			return null;
		}
		return resource.getLocation().toOSString();
	}
}

MirahNature.java

package org.mirah.core.builder;

import org.eclipse.core.resources.ICommand;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IProjectDescription;
import org.eclipse.core.resources.IProjectNature;
import org.eclipse.core.runtime.CoreException;

public class MirahNature implements IProjectNature {

	/**
	 * ID of this project nature
	 */
	public static final String NATURE_ID = "org.mirah.core.mirahNature";

	private IProject project;

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.resources.IProjectNature#configure()
	 */
	public void configure() throws CoreException {
		IProjectDescription desc = project.getDescription();
		ICommand[] commands = desc.getBuildSpec();

		for (int i = 0; i < commands.length; ++i) {
			if (commands[i].getBuilderName().equals(MirahBuilder.BUILDER_ID)) {
				return;
			}
		}

		ICommand[] newCommands = new ICommand[commands.length + 1];
		System.arraycopy(commands, 0, newCommands, 0, commands.length);
		ICommand command = desc.newCommand();
		command.setBuilderName(MirahBuilder.BUILDER_ID);
		newCommands[newCommands.length - 1] = command;
		desc.setBuildSpec(newCommands);
		project.setDescription(desc, null);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.resources.IProjectNature#deconfigure()
	 */
	public void deconfigure() throws CoreException {
		IProjectDescription description = getProject().getDescription();
		ICommand[] commands = description.getBuildSpec();
		for (int i = 0; i < commands.length; ++i) {
			if (commands[i].getBuilderName().equals(MirahBuilder.BUILDER_ID)) {
				ICommand[] newCommands = new ICommand[commands.length - 1];
				System.arraycopy(commands, 0, newCommands, 0, i);
				System.arraycopy(commands, i + 1, newCommands, i,
						commands.length - i - 1);
				description.setBuildSpec(newCommands);
				project.setDescription(description, null);			
				return;
			}
		}
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.resources.IProjectNature#getProject()
	 */
	public IProject getProject() {
		return project;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.resources.IProjectNature#setProject(org.eclipse.core.resources.IProject)
	 */
	public void setProject(IProject project) {
		this.project = project;
	}

}