GroovyClassFileWorkingCopy.java

/*******************************************************************************
 * Copyright (c) 2012 Pivotal Software, Inc.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Pivotal Software, Inc. - initial API and implementation
 *******************************************************************************/
package org.grails.ide.eclipse.editor.groovy.elements;

import org.codehaus.groovy.ast.ModuleNode;
import org.codehaus.jdt.groovy.internal.compiler.ast.GroovyCompilationUnitDeclaration;
import org.codehaus.jdt.groovy.model.GroovyCompilationUnit;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.jdt.core.IBuffer;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IJavaModelStatusConstants;
import org.eclipse.jdt.core.JavaModelException;
import org.eclipse.jdt.core.ToolFactory;
import org.eclipse.jdt.core.WorkingCopyOwner;
import org.eclipse.jdt.core.compiler.CharOperation;
import org.eclipse.jdt.core.util.ClassFileBytesDisassembler;
import org.eclipse.jdt.core.util.IClassFileReader;
import org.eclipse.jdt.groovy.core.util.ReflectionUtils;
import org.eclipse.jdt.internal.core.BinaryType;
import org.eclipse.jdt.internal.core.BufferManager;
import org.eclipse.jdt.internal.core.ClassFile;
import org.eclipse.jdt.internal.core.ClassFileWorkingCopy;
import org.eclipse.jdt.internal.core.CompilationUnitElementInfo;
import org.eclipse.jdt.internal.core.DefaultWorkingCopyOwner;
import org.eclipse.jdt.internal.core.JavaModelManager.PerWorkingCopyInfo;
import org.eclipse.jdt.internal.core.JavaModelStatus;
import org.eclipse.jdt.internal.core.Openable;
import org.eclipse.jdt.internal.core.PackageFragment;
import org.eclipse.jdt.internal.core.PackageFragmentRoot;
import org.eclipse.jdt.internal.core.util.Disassembler;
import org.eclipse.jdt.internal.core.util.Util;
import org.grails.ide.eclipse.core.GrailsCoreActivator;


/**
 * Working copy for groovy class files.  Allows access to the 
 * ModuleNode for class files if the source is available.
 * Copied from {@link ClassFileWorkingCopy} Groovy changes marked
 * @author Andrew Eisenberg
 * @author Christian Dupuis
 * @created Dec 11, 2009
 */
public class GroovyClassFileWorkingCopy extends GroovyCompilationUnit {

    public ClassFile classFile;
    
    // GROOVY Change
    private final PerWorkingCopyInfo info;
    private CompilationUnitElementInfo elementInfo;
    private ModuleNode moduleNode;
    // GROOVY End

    public GroovyClassFileWorkingCopy(ClassFile classFile, WorkingCopyOwner owner) {
        super((PackageFragment) classFile.getParent(), ((BinaryType) classFile.getType()).getSourceFileName(null/*no info available*/), owner);
        this.classFile = classFile;
        // GROOVY Change
        info = new PerWorkingCopyInfo(this, null);
        // GROOVY End
    }

    public void commitWorkingCopy(boolean force, IProgressMonitor monitor) throws JavaModelException {
        throw new JavaModelException(new JavaModelStatus(IJavaModelStatusConstants.INVALID_ELEMENT_TYPES, this));
    }

    public IBuffer getBuffer() throws JavaModelException {
        // GROOVY Always use the classFile's buffer
        // old
        //        if (isWorkingCopy())
        //            return super.getBuffer();
        //          else
        // GROOVY end
        return this.classFile.getBuffer();
    }

    public char[] getContents() {
        try {
            IBuffer buffer = getBuffer();
            if (buffer == null) return CharOperation.NO_CHAR;
            char[] characters = buffer.getCharacters();
            if (characters == null) return CharOperation.NO_CHAR;
            return characters;
        } catch (JavaModelException e) {
            return CharOperation.NO_CHAR;
        }
    }

    public IPath getPath() {
        return this.classFile.getPath();
    }

    public IJavaElement getPrimaryElement(boolean checkOwner) {
        if (checkOwner && isPrimary()) return this;
        return new ClassFileWorkingCopy(this.classFile, DefaultWorkingCopyOwner.PRIMARY);
    }

    public IResource resource(PackageFragmentRoot root) {
        if (root.isArchive())
            return root.resource(root);
        return this.classFile.resource(root);
    }

    /**
     * @see Openable#openBuffer(IProgressMonitor, Object)
     */
    protected IBuffer openBuffer(IProgressMonitor pm, Object info) throws JavaModelException {

        // create buffer
        IBuffer buffer = this.owner.createBuffer(this);
        if (buffer == null) return null;

        // set the buffer source
        if (buffer.getCharacters() == null) {
            IBuffer classFileBuffer = this.classFile.getBuffer();
            if (classFileBuffer != null) {
                buffer.setContents(classFileBuffer.getCharacters());
            } else {
                // Disassemble
                IClassFileReader reader = ToolFactory.createDefaultClassFileReader(this.classFile, IClassFileReader.ALL);
                Disassembler disassembler = new Disassembler();
                String contents = disassembler.disassemble(reader, Util.getLineSeparator("", getJavaProject()), ClassFileBytesDisassembler.WORKING_COPY); //$NON-NLS-1$
                buffer.setContents(contents);
            }
        }

        // add buffer to buffer cache
        BufferManager bufManager = getBufferManager();
        
        // GROOVY Change access to private member
        // old
        // bufManager.addBuffer(buffer);
        // new
        if (buffer.getContents() != null) {
            ReflectionUtils.executePrivateMethod(BufferManager.class, "addBuffer", new Class<?>[] {IBuffer.class }, bufManager, new Object[] { buffer }); //$NON-NLS-1$
        }
        // GROOVY End
        
        // listen to buffer changes
        buffer.addBufferChangedListener(this);

        return buffer;
    }

    protected void toStringName(StringBuffer buffer) {
        buffer.append(this.classFile.getElementName());
    }

    // GROOVY Change
    // all be a working copy
    // build structure only needs to happen once.
    @Override
    public PerWorkingCopyInfo getPerWorkingCopyInfo() {
        if (elementInfo == null) {
            try {
                elementInfo = (CompilationUnitElementInfo) createElementInfo();
                // FIXADE in E4.2, this method takes 3 args
                // when no longer supporting E3.7, then remove this
                // and uncomment the line below
                openWhenClosed(elementInfo, new NullProgressMonitor());
//                openWhenClosed(elementInfo, true, new NullProgressMonitor());
            } catch (JavaModelException e) {
                elementInfo = null;
                GrailsCoreActivator.log(e.getJavaModelStatus());
            }
        }
        return info;
    }
    

    /**
     * Cache module node locally and not in the mapper
     */
    @Override
    protected void maybeCacheModuleNode(PerWorkingCopyInfo perWorkingCopyInfo,
            GroovyCompilationUnitDeclaration compilationUnitDeclaration) {
        if (compilationUnitDeclaration != null) {
            moduleNode = compilationUnitDeclaration.getModuleNode();
        }
    }
    
    /**
     * ModuleNode is not cached in the Mapper, but rather cached locally
     */
    @Override
    public ModuleNode getModuleNode() {
        // ensure moduleNode is initialized
        getPerWorkingCopyInfo();
        return moduleNode;
    }
    
    @Override
    public IResource resource() {
        return getJavaProject().getResource();
    }
    
    
    @Override
    public char[] getFileName() {
        return (this.classFile.getType().getElementName() + ".groovy").toCharArray(); //$NON-NLS-1$
    }
    
    @Override
    public boolean isOnBuildPath() {
        // a call to super.isOnBuildPath() will always return false,
        // but it should be true
        return true;
    }
    // GROOVY End
}