Java tutorial
/** * Copyright (C) 2005 - 2013 Eric Van Dewoestine * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package org.eclim.plugin.jdt.util; import org.eclim.logging.Logger; import org.eclipse.jdt.core.IClassFile; import org.eclipse.jdt.core.ICompilationUnit; import org.eclipse.jdt.core.IJavaElement; import org.eclipse.jdt.core.dom.AST; import org.eclipse.jdt.core.dom.ASTNode; import org.eclipse.jdt.core.dom.ASTParser; import org.eclipse.jdt.core.dom.AbstractTypeDeclaration; import org.eclipse.jdt.core.dom.CompilationUnit; import org.eclipse.jdt.core.dom.FieldDeclaration; import org.eclipse.jdt.core.dom.ImportDeclaration; import org.eclipse.jdt.core.dom.Initializer; import org.eclipse.jdt.core.dom.MethodDeclaration; import org.eclipse.jdt.core.dom.NodeFinder; import org.eclipse.jdt.core.dom.PackageDeclaration; import org.eclipse.jface.text.Document; import org.eclipse.text.edits.TextEdit; /** * Utility class for working with the eclipse java dom model. * * @author Eric Van Dewoestine */ public class ASTUtils { private static final Logger logger = Logger.getLogger(ASTUtils.class); private ASTUtils() { } /** * Gets the AST CompilationUnit for the supplied ICompilationUnit. * <p/> * Equivalent of getCompilationUnit(src, false). * * @param src The ICompilationUnit. * @return The CompilationUnit. */ public static CompilationUnit getCompilationUnit(ICompilationUnit src) throws Exception { return getCompilationUnit(src, false); } /** * Gets the AST CompilationUnit for the supplied ICompilationUnit. * * @param src The ICompilationUnit. * @param recordModifications true to record any modifications, false * otherwise. * @return The CompilationUnit. */ public static CompilationUnit getCompilationUnit(ICompilationUnit src, boolean recordModifications) throws Exception { ASTParser parser = ASTParser.newParser(AST.JLS4); parser.setSource(src); CompilationUnit cu = (CompilationUnit) parser.createAST(null); if (recordModifications) { cu.recordModifications(); } return cu; } /** * Gets the AST CompilationUnit for the supplied IClassFile. * * @param clazz The IClassFile. * @return The CompilationUnit. */ public static CompilationUnit getCompilationUnit(IClassFile clazz) throws Exception { ASTParser parser = ASTParser.newParser(AST.JLS4); parser.setSource(clazz); return (CompilationUnit) parser.createAST(null); } /** * Commits any changes made to the supplied CompilationUnit. * <p/> * Note: The method expects that the CompilationUnit is recording the * modifications (getCompilationUnit(src, true) was used). * * @param src The original ICompilationUnit. * @param node The CompilationUnit ast node. */ public static void commitCompilationUnit(ICompilationUnit src, CompilationUnit node) throws Exception { Document document = new Document(src.getBuffer().getContents()); TextEdit edits = node.rewrite(document, src.getJavaProject().getOptions(true)); edits.apply(document); src.getBuffer().setContents(document.get()); if (src.isWorkingCopy()) { src.commitWorkingCopy(false, null); } src.save(null, false); } /** * Finds the node at the specified offset. * * @param cu The CompilationUnit. * @param offset The node offset in the compilation unit. * @return The node at the specified offset. */ public static ASTNode findNode(CompilationUnit cu, int offset) throws Exception { NodeFinder finder = new NodeFinder(cu, offset, 1); //return finder.getCoveredNode(); return finder.getCoveringNode(); } /** * Finds the node at the specified offset that matches up with the supplied * IJavaElement. * * @param cu The CompilationUnit. * @param offset The node offset in the compilation unit. * @param element The IJavaElement to match. * @return The node at the specified offset. */ public static ASTNode findNode(CompilationUnit cu, int offset, IJavaElement element) throws Exception { ASTNode node = findNode(cu, offset); if (node == null) { return null; } if (element.getElementType() == IJavaElement.TYPE_PARAMETER) { element = element.getParent(); } switch (element.getElementType()) { case IJavaElement.PACKAGE_DECLARATION: node = resolveNode(node, PackageDeclaration.class); break; case IJavaElement.IMPORT_DECLARATION: node = resolveNode(node, ImportDeclaration.class); break; case IJavaElement.TYPE: node = resolveNode(node, AbstractTypeDeclaration.class); break; case IJavaElement.INITIALIZER: node = resolveNode(node, Initializer.class); break; case IJavaElement.FIELD: node = resolveNode(node, FieldDeclaration.class); break; case IJavaElement.METHOD: node = resolveNode(node, MethodDeclaration.class); break; default: logger.info("findNode(CompilationUnit,int,IJavaElement) - " + "unrecognized element type " + element.getElementType()); } return node; } /** * Walk up the node tree until a node of the specified type is reached. * * @param node The starting node. * @param type The type to resolve. * @return The resulting node. */ @SuppressWarnings({ "rawtypes", "unchecked" }) private static ASTNode resolveNode(ASTNode node, Class type) throws Exception { if (node == null) { return null; } if (type.isAssignableFrom(node.getClass())) { return node; } return resolveNode(node.getParent(), type); } }