001    /*
002     * Sonar, open source software quality management tool.
003     * Copyright (C) 2009 SonarSource SA
004     * mailto:contact AT sonarsource DOT com
005     *
006     * Sonar is free software; you can redistribute it and/or
007     * modify it under the terms of the GNU Lesser General Public
008     * License as published by the Free Software Foundation; either
009     * version 3 of the License, or (at your option) any later version.
010     *
011     * Sonar is distributed in the hope that it will be useful,
012     * but WITHOUT ANY WARRANTY; without even the implied warranty of
013     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014     * Lesser General Public License for more details.
015     *
016     * You should have received a copy of the GNU Lesser General Public
017     * License along with Sonar; if not, write to the Free Software
018     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
019     */
020    package org.sonar.java.bytecode.asm;
021    
022    import org.objectweb.asm.ClassReader;
023    import org.objectweb.asm.util.TraceClassVisitor;
024    import org.slf4j.Logger;
025    import org.slf4j.LoggerFactory;
026    
027    import java.io.IOException;
028    import java.io.PrintWriter;
029    import java.util.HashMap;
030    import java.util.Map;
031    
032    public class AsmClassProviderImpl extends AsmClassProvider {
033    
034      private static Logger logger = LoggerFactory.getLogger(AsmClassProviderImpl.class);
035      private final ClassLoader classLoader;
036      private Map<String, AsmClass> asmClassCache = new HashMap<String, AsmClass>();
037    
038      public AsmClassProviderImpl() {
039        this.classLoader = Thread.currentThread().getContextClassLoader();
040      }
041    
042      public AsmClassProviderImpl(ClassLoader classLoader) {
043        this.classLoader = classLoader;
044      }
045    
046      public AsmClass getClass(String internalName, DETAIL_LEVEL level) {
047        if (internalName == null) {
048          throw new IllegalStateException("You can try to load a class whose internalName = 'null'");
049        }
050        AsmClass asmClass = getAsmClassFromCacheOrCreateIt(internalName);
051        if (level.isGreaterThan(asmClass.getDetailLevel())) {
052          decoracteAsmClassFromBytecode(asmClass, level);
053        }
054        return asmClass;
055      }
056    
057      private AsmClass getAsmClassFromCacheOrCreateIt(String internalName) {
058        AsmClass asmClass = asmClassCache.get(internalName);
059        if (asmClass == null) {
060          asmClass = new AsmClass(internalName, DETAIL_LEVEL.NOTHING);
061          asmClassCache.put(internalName, asmClass);
062        }
063        return asmClass;
064      }
065    
066      private void decoracteAsmClassFromBytecode(AsmClass asmClass, DETAIL_LEVEL level) {
067        try {
068          AsmClassVisitor classVisitor = new AsmClassVisitor(this, asmClass, level);
069          ClassReader asmReader = new ClassReader(classLoader.getResourceAsStream(asmClass.getInternalName() + ".class"));
070          asmReader.accept(classVisitor, 0);
071        } catch (IOException e) {
072          logger.warn("Class '" + asmClass.getInternalName() + "' is not accessible through the ClassLoader.");
073        }
074      }
075    
076      public final void printClassBytecode(String internalName) {
077        try {
078          TraceClassVisitor classVisitor = new TraceClassVisitor(new PrintWriter(System.out));
079          ClassReader asmReader = new ClassReader(classLoader.getResourceAsStream(internalName + ".class"));
080          asmReader.accept(classVisitor, 0);
081        } catch (IOException e) {
082          logger.info("Class '" + internalName + "' is not accessible through the ClassLoader.");
083        }
084      }
085    }