FindBugsNature.java

/*
 * FindBugs Eclipse Plug-in.
 * Copyright (C) 2003 - 2004, Peter Friese
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

package de.tobject.findbugs.nature;

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;

import de.tobject.findbugs.FindbugsPlugin;
import de.tobject.findbugs.reporter.MarkerUtil;

/**
 * This is the nature for FindBugs-enabled projects.
 * 
 * @author Peter Friese
 * @version 1.0
 * @since 25.9.2003
 * @see IProjectNature
 */
public class FindBugsNature implements IProjectNature {

    /** Controls debugging of the nature */
    public static boolean DEBUG;

    /** project reference */
    private IProject project;

    /**
     * Adds the FindBugs builder to the project.
     * 
     * @see IProjectNature#configure
     */
    public void configure() throws CoreException {
        if (DEBUG) {
            System.out.println("Adding findbugs to the project build spec.");
        }
        // register FindBugs builder
        addToBuildSpec(FindbugsPlugin.BUILDER_ID);
    }

    /**
     * Removes the FindBugs builder from the project.
     * 
     * @see IProjectNature#deconfigure
     */
    public void deconfigure() throws CoreException {
        if (DEBUG) {
            System.out.println("Removing findbugs from the project build spec.");
        }
        // de-register FindBugs builder
        removeFromBuildSpec(FindbugsPlugin.BUILDER_ID);
    }

    /**
     * Removes the given builder from the build spec for the given project.
     */
    protected void removeFromBuildSpec(String builderID) throws CoreException {
        MarkerUtil.removeMarkers(getProject());
        IProjectDescription description = getProject().getDescription();
        ICommand[] commands = description.getBuildSpec();
        for (int i = 0; i < commands.length; ++i) {
            if (commands[i].getBuilderName().equals(builderID)) {
                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);
                getProject().setDescription(description, null);
                return;
            }
        }
    }

    /**
     * Adds a builder to the build spec for the given project.
     */
    protected void addToBuildSpec(String builderID) throws CoreException {
        IProjectDescription description = getProject().getDescription();
        ICommand findBugsCommand = getFindBugsCommand(description);
        if (findBugsCommand == null) {
            // Add a Java command to the build spec
            ICommand newCommand = description.newCommand();
            newCommand.setBuilderName(builderID);
            setFindBugsCommand(description, newCommand);
        }
    }

    /**
     * Find the specific FindBugs command amongst the build spec of a given
     * description
     */
    private ICommand getFindBugsCommand(IProjectDescription description) {
        ICommand[] commands = description.getBuildSpec();
        for (int i = 0; i < commands.length; ++i) {
            if (commands[i].getBuilderName().equals(FindbugsPlugin.BUILDER_ID)) {
                return commands[i];
            }
        }
        return null;
    }

    /**
     * Update the FindBugs command in the build spec (replace existing one if
     * present, add one first if none).
     */
    private void setFindBugsCommand(IProjectDescription description, ICommand newCommand) throws CoreException {
        ICommand[] oldCommands = description.getBuildSpec();
        ICommand oldFindBugsCommand = getFindBugsCommand(description);
        ICommand[] newCommands;
        if (oldFindBugsCommand == null) {
            // Add the FindBugs build spec AFTER all other builders
            newCommands = new ICommand[oldCommands.length + 1];
            System.arraycopy(oldCommands, 0, newCommands, 0, oldCommands.length);
            newCommands[oldCommands.length] = newCommand;
        } else {
            for (int i = 0, max = oldCommands.length; i < max; i++) {
                if (oldCommands[i] == oldFindBugsCommand) {
                    oldCommands[i] = newCommand;
                    break;
                }
            }
            newCommands = oldCommands;
        }
        // Commit the spec change into the project
        description.setBuildSpec(newCommands);
        getProject().setDescription(description, null);
    }

    /**
     * Returns the project reference.
     * 
     * @see IProjectNature#getProject
     */
    public IProject getProject() {
        return this.project;
    }

    /**
     * Sets the project reference.
     * 
     * @see IProjectNature#setProject
     */
    public void setProject(IProject project) {
        this.project = project;
    }

}