com.google.gdt.eclipse.designer.uibinder.refactoring.UiFieldRenameParticipant.java Source code

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/*******************************************************************************
 * Copyright 2011 Google Inc. All Rights Reserved.
 *
 * 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
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package com.google.gdt.eclipse.designer.uibinder.refactoring;

import com.google.gdt.eclipse.designer.uibinder.editor.UiBinderPairResourceProvider;
import com.google.gdt.eclipse.designer.uibinder.model.util.NameSupport;

import org.eclipse.wb.internal.core.utils.execution.ExecutionUtils;
import org.eclipse.wb.internal.core.utils.execution.RunnableObjectEx;
import org.eclipse.wb.internal.core.utils.refactoring.RefactoringUtils;
import org.eclipse.wb.internal.core.utils.reflect.ReflectionUtils;
import org.eclipse.wb.internal.core.utils.xml.DocumentAttribute;
import org.eclipse.wb.internal.core.utils.xml.DocumentModelVisitor;
import org.eclipse.wb.internal.core.utils.xml.FileDocumentEditContext;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.jdt.core.IAnnotation;
import org.eclipse.jdt.core.IField;
import org.eclipse.jdt.core.IMethod;
import org.eclipse.jdt.core.ISourceRange;
import org.eclipse.jdt.core.IType;
import org.eclipse.jdt.core.refactoring.CompilationUnitChange;
import org.eclipse.jdt.ui.refactoring.RenameSupport;
import org.eclipse.ltk.core.refactoring.Change;
import org.eclipse.ltk.core.refactoring.CompositeChange;
import org.eclipse.ltk.core.refactoring.RefactoringStatus;
import org.eclipse.ltk.core.refactoring.TextChange;
import org.eclipse.ltk.core.refactoring.participants.CheckConditionsContext;
import org.eclipse.ltk.core.refactoring.participants.RenameParticipant;
import org.eclipse.ltk.core.refactoring.participants.RenameRefactoring;
import org.eclipse.text.edits.MultiTextEdit;
import org.eclipse.text.edits.ReplaceEdit;
import org.eclipse.text.edits.TextEdit;

import org.apache.commons.lang.StringUtils;

/**
 * Participates in rename of "@UiField".
 * 
 * @author scheglov_ke
 * @coverage GWT.UiBinder.refactoring
 */
public class UiFieldRenameParticipant extends RenameParticipant {
    protected IField m_field;
    private String m_oldName;
    private String m_newName;

    ////////////////////////////////////////////////////////////////////////////
    //
    // RefactoringParticipant
    //
    ////////////////////////////////////////////////////////////////////////////
    @Override
    public String getName() {
        return "UiField rename participant";
    }

    @Override
    protected boolean initialize(Object element) {
        m_field = (IField) element;
        return true;
    }

    @Override
    public RefactoringStatus checkConditions(IProgressMonitor pm, CheckConditionsContext context) {
        return new RefactoringStatus();
    }

    ////////////////////////////////////////////////////////////////////////////
    //
    // Change
    //
    ////////////////////////////////////////////////////////////////////////////
    @Override
    public final Change createChange(final IProgressMonitor pm) {
        return ExecutionUtils.runObjectLog(new RunnableObjectEx<Change>() {
            public Change runObject() throws Exception {
                return createChangeEx(pm);
            }
        }, null);
    }

    /**
     * Implementation of {@link #createChange(IProgressMonitor)} that can throw {@link Exception}.
     */
    private Change createChangeEx(IProgressMonitor pm) throws Exception {
        CompositeChange compositeChange = new CompositeChange("synthetic");
        compositeChange.markAsSynthetic();
        // prepare context
        m_oldName = m_field.getElementName();
        m_newName = getArguments().getNewName();
        // add changes
        addHandlerMethodChanges(compositeChange, pm);
        compositeChange.add(createTemplateChange());
        return compositeChange;
    }

    /**
     * Adds {@link TextEdit}s into existing Java file {@link Change}.
     */
    private void addHandlerMethodChanges(CompositeChange compositeChange, IProgressMonitor pm) throws Exception {
        TextChange change = new CompilationUnitChange("(No matter)", m_field.getCompilationUnit());
        change.setEdit(new MultiTextEdit());
        // update handler methods
        String oldMethodPrefix = "on" + StringUtils.capitalize(m_oldName);
        String newMethodPrefix = "on" + StringUtils.capitalize(m_newName);
        IType type = (IType) m_field.getParent();
        for (IMethod method : type.getMethods()) {
            // prepare @UiHandler annotation
            IAnnotation annotation = getHandlerAnnotation(method);
            if (annotation == null) {
                continue;
            }
            // update @UiHandler name
            {
                ISourceRange annoRange = annotation.getSourceRange();
                ISourceRange nameRange = annotation.getNameRange();
                int nameEnd = nameRange.getOffset() + nameRange.getLength();
                int annoEnd = annoRange.getOffset() + annoRange.getLength();
                change.addEdit(new ReplaceEdit(nameEnd, annoEnd - nameEnd, "(\"" + m_newName + "\")"));
            }
            // rename method
            String methodName = method.getElementName();
            if (methodName.startsWith(oldMethodPrefix)) {
                String newName = newMethodPrefix + StringUtils.removeStart(methodName, oldMethodPrefix);
                Change renameChange = createRenameChange(method, newName, pm);
                compositeChange.add(renameChange);
                RefactoringUtils.mergeTextChange(this, renameChange);
            }
        }
        // merge edits into existing (rename) change
        RefactoringUtils.mergeTextChange(this, change);
    }

    /**
     * @return the "@UiHandler" {@link IAnnotation}, may be <code>null</code>.
     */
    private IAnnotation getHandlerAnnotation(IMethod method) throws Exception {
        for (IAnnotation annotation : method.getAnnotations()) {
            if (annotation.getElementName().equals("UiHandler")
                    && annotation.getMemberValuePairs()[0].getValue().equals(m_oldName)) {
                return annotation;
            }
        }
        return null;
    }

    /**
     * @return the {@link Change} to rename given {@link IMethod}.
     */
    private static Change createRenameChange(IMethod method, String newName, IProgressMonitor pm) throws Exception {
        RenameSupport renameSupport = RenameSupport.create(method, newName, RenameSupport.UPDATE_REFERENCES);
        RenameRefactoring refactoring = (RenameRefactoring) ReflectionUtils.getFieldObject(renameSupport,
                "fRefactoring");
        refactoring.checkAllConditions(pm);
        return refactoring.createChange(pm);
    }

    /**
     * @return the <code>*.ui.xml</code> file {@link Change}.
     */
    private Change createTemplateChange() throws Exception {
        if (NameSupport.isRenaming()) {
            return null;
        }
        IFile javaFile = (IFile) m_field.getUnderlyingResource();
        IFile uiFile = UiBinderPairResourceProvider.INSTANCE.getPair(javaFile);
        // field from not UiBinder unit
        if (uiFile == null) {
            return null;
        }
        // prepare change
        return RefactoringUtils.modifyXML(uiFile, new DocumentModelVisitor() {
            @Override
            public void visit(DocumentAttribute attribute) {
                if (attribute.getName().endsWith(":field") && attribute.getValue().equals(m_oldName)) {
                    attribute.setValue(m_newName);
                }
            }
        }, new FileDocumentEditContext(uiFile));
    }
}