lubomir@1084: /**
lubomir@1084:  * Back 2 Browser Bytecode Translator
jaroslav@1787:  * Copyright (C) 2012-2015 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
lubomir@1084:  *
lubomir@1084:  * This program is free software: you can redistribute it and/or modify
lubomir@1084:  * it under the terms of the GNU General Public License as published by
lubomir@1084:  * the Free Software Foundation, version 2 of the License.
lubomir@1084:  *
lubomir@1084:  * This program is distributed in the hope that it will be useful,
lubomir@1084:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
lubomir@1084:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
lubomir@1084:  * GNU General Public License for more details.
lubomir@1084:  *
lubomir@1084:  * You should have received a copy of the GNU General Public License
lubomir@1084:  * along with this program. Look for COPYING file in the top folder.
lubomir@1084:  * If not, see http://opensource.org/licenses/GPL-2.0.
lubomir@1084:  */
lubomir@1084: package org.apidesign.vm4brwsr;
lubomir@1084: 
lubomir@1084: import java.io.IOException;
lubomir@1084: import java.io.InputStream;
lubomir@1084: import java.util.HashMap;
lubomir@1084: import java.util.Map;
lubomir@1084: import org.apidesign.bck2brwsr.core.ExtraJavaScript;
lubomir@1084: import org.apidesign.vm4brwsr.ByteCodeParser.ClassData;
lubomir@1085: import org.apidesign.vm4brwsr.ByteCodeParser.FieldData;
lubomir@1085: import org.apidesign.vm4brwsr.ByteCodeParser.MethodData;
lubomir@1084: 
lubomir@1084: @ExtraJavaScript(processByteCode = false, resource="")
lubomir@1084: final class ClassDataCache {
lubomir@1084:     private static final Object MISSING_CLASS = new Object();
lubomir@1084: 
lubomir@1084:     private final Bck2Brwsr.Resources resources;
lubomir@1084:     private final Map<String, Object> classDataMap;
lubomir@1084: 
lubomir@1084:     ClassDataCache(final Bck2Brwsr.Resources resources) {
lubomir@1084:         this.resources = resources;
lubomir@1084: 
lubomir@1084:         classDataMap = new HashMap<String, Object>();
lubomir@1084:     }
lubomir@1084: 
lubomir@1085:     ClassData getClassData(String className) throws IOException {
lubomir@1085:         if (className.startsWith("[")) {
lubomir@1085:             // required for accessVirtualMethod, shouldn't be problematic for
lubomir@1085:             // calls from other sources
lubomir@1085:             className = "java/lang/Object";
lubomir@1085:         }
lubomir@1084:         Object cacheEntry = classDataMap.get(className);
lubomir@1084:         if (cacheEntry == null) {
lubomir@1084:             final InputStream is = loadClass(resources, className);
lubomir@1084:             cacheEntry = (is != null) ? new ClassData(is) : MISSING_CLASS;
lubomir@1084:             classDataMap.put(className, cacheEntry);
lubomir@1084:         }
lubomir@1084: 
lubomir@1084:         return (cacheEntry != MISSING_CLASS) ? (ClassData) cacheEntry : null;
lubomir@1084:     }
lubomir@1084: 
lubomir@1085:     MethodData findMethod(final String startingClass,
lubomir@1085:                           final String name,
lubomir@1085:                           final String signature) throws IOException {
lubomir@1085:         return findMethod(getClassData(startingClass), name, signature);
lubomir@1085:     }
lubomir@1085: 
lubomir@1085:     FieldData findField(final String startingClass,
lubomir@1085:                         final String name,
lubomir@1085:                         final String signature) throws IOException {
lubomir@1085:         return findField(getClassData(startingClass), name, signature);
lubomir@1085:     }
lubomir@1085: 
lubomir@1087:     MethodData findMethod(final ClassData startingClass,
lubomir@1085:                           final String name,
lubomir@1085:                           final String signature) throws IOException {
lubomir@1087:         final FindFirstTraversalCallback<MethodData> ffTraversalCallback =
lubomir@1087:                 new FindFirstTraversalCallback<MethodData>();
lubomir@1087: 
lubomir@1087:         findMethods(startingClass, name, signature, ffTraversalCallback);
lubomir@1087:         return ffTraversalCallback.getFirst();
lubomir@1087:     }
lubomir@1087: 
lubomir@1087:     FieldData findField(final ClassData startingClass,
lubomir@1087:                         final String name,
lubomir@1087:                         final String signature) throws IOException {
lubomir@1087:         final FindFirstTraversalCallback<FieldData> ffTraversalCallback =
lubomir@1087:                 new FindFirstTraversalCallback<FieldData>();
lubomir@1087: 
lubomir@1087:         findFields(startingClass, name, signature, ffTraversalCallback);
lubomir@1087:         return ffTraversalCallback.getFirst();
lubomir@1087:     }
lubomir@1087: 
lubomir@1087:     void findMethods(final ClassData startingClass,
lubomir@1087:                      final String methodName,
lubomir@1087:                      final String methodSignature,
lubomir@1087:                      final TraversalCallback<MethodData> mdTraversalCallback)
lubomir@1087:                              throws IOException {
lubomir@1087:         traverseHierarchy(
lubomir@1087:                 startingClass,
lubomir@1087:                 new FindMethodsTraversalCallback(methodName, methodSignature,
lubomir@1087:                                                  mdTraversalCallback));
lubomir@1087:     }
lubomir@1087: 
lubomir@1087:     void findFields(final ClassData startingClass,
lubomir@1087:                     final String fieldName,
lubomir@1087:                     final String fieldSignature,
lubomir@1087:                     final TraversalCallback<FieldData> fdTraversalCallback)
lubomir@1087:                             throws IOException {
lubomir@1087:         traverseHierarchy(
lubomir@1087:                 startingClass,
lubomir@1087:                 new FindFieldsTraversalCallback(fieldName, fieldSignature,
lubomir@1087:                                                 fdTraversalCallback));
lubomir@1087:     }
lubomir@1087: 
lubomir@1087:     private boolean traverseHierarchy(
lubomir@1087:             ClassData currentClass,
lubomir@1087:             final TraversalCallback<ClassData> cdTraversalCallback)
lubomir@1087:                 throws IOException {
lubomir@1085:         while (currentClass != null) {
lubomir@1087:             if (!cdTraversalCallback.traverse(currentClass)) {
lubomir@1087:                 return false;
lubomir@1087:             }
lubomir@1087: 
lubomir@1087:             for (final String superIfaceName:
lubomir@1087:                     currentClass.getSuperInterfaces()) {
lubomir@1087:                 if (!traverseHierarchy(getClassData(superIfaceName),
lubomir@1087:                                        cdTraversalCallback)) {
lubomir@1087:                     return false;
lubomir@1087:                 }
lubomir@1085:             }
lubomir@1085: 
lubomir@1085:             final String superClassName = currentClass.getSuperClassName();
lubomir@1085:             if (superClassName == null) {
lubomir@1085:                 break;
lubomir@1085:             }
lubomir@1087: 
lubomir@1085:             currentClass = getClassData(superClassName);
lubomir@1085:         }
lubomir@1085: 
lubomir@1087:         return true;
lubomir@1085:     }
lubomir@1085: 
lubomir@1087:     interface TraversalCallback<T> {
lubomir@1087:         boolean traverse(T object);
lubomir@1087:     }
lubomir@1085: 
lubomir@1087:     private final class FindFirstTraversalCallback<T>
lubomir@1087:             implements TraversalCallback<T> {
lubomir@1087:         private T firstObject;
lubomir@1087: 
lubomir@1087:         @Override
lubomir@1087:         public boolean traverse(final T object) {
lubomir@1087:             firstObject = object;
lubomir@1087:             return false;
lubomir@1085:         }
lubomir@1085: 
lubomir@1087:         public T getFirst() {
lubomir@1087:             return firstObject;
lubomir@1087:         }
lubomir@1087:     }
lubomir@1087: 
lubomir@1087:     private final class FindMethodsTraversalCallback
lubomir@1087:             implements TraversalCallback<ClassData> {
lubomir@1087:         private final String methodName;
lubomir@1087:         private final String methodSignature;
lubomir@1087:         private final TraversalCallback<MethodData> mdTraversalCallback;
lubomir@1087: 
lubomir@1087:         public FindMethodsTraversalCallback(
lubomir@1087:                 final String methodName,
lubomir@1087:                 final String methodSignature,
lubomir@1087:                 final TraversalCallback<MethodData> mdTraversalCallback) {
lubomir@1087:             this.methodName = methodName;
lubomir@1087:             this.methodSignature = methodSignature;
lubomir@1087:             this.mdTraversalCallback = mdTraversalCallback;
lubomir@1087:         }
lubomir@1087: 
lubomir@1087:         @Override
lubomir@1087:         public boolean traverse(final ClassData classData) {
lubomir@1087:             final MethodData methodData =
lubomir@1087:                     classData.findMethod(methodName, methodSignature);
lubomir@1087:             return (methodData != null)
lubomir@1087:                        ? mdTraversalCallback.traverse(methodData)
lubomir@1087:                        : true;
lubomir@1087:         }
lubomir@1087:     }
lubomir@1087: 
lubomir@1087:     private final class FindFieldsTraversalCallback
lubomir@1087:             implements TraversalCallback<ClassData> {
lubomir@1087:         private final String fieldName;
lubomir@1087:         private final String fieldSignature;
lubomir@1087:         private final TraversalCallback<FieldData> fdTraversalCallback;
lubomir@1087: 
lubomir@1087:         public FindFieldsTraversalCallback(
lubomir@1087:                 final String fieldName,
lubomir@1087:                 final String fieldSignature,
lubomir@1087:                 final TraversalCallback<FieldData> fdTraversalCallback) {
lubomir@1087:             this.fieldName = fieldName;
lubomir@1087:             this.fieldSignature = fieldSignature;
lubomir@1087:             this.fdTraversalCallback = fdTraversalCallback;
lubomir@1087:         }
lubomir@1087: 
lubomir@1087:         @Override
lubomir@1087:         public boolean traverse(final ClassData classData) {
lubomir@1087:             final FieldData fieldData =
lubomir@1087:                     classData.findField(fieldName, fieldSignature);
lubomir@1087:             return (fieldData != null)
lubomir@1087:                        ? fdTraversalCallback.traverse(fieldData)
lubomir@1087:                        : true;
lubomir@1087:         }
lubomir@1085:     }
lubomir@1085: 
lubomir@1084:     private static InputStream loadClass(Bck2Brwsr.Resources l, String name)
lubomir@1084:             throws IOException {
lubomir@1084:         return l.get(name + ".class"); // NOI18N
lubomir@1084:     }
lubomir@1084: }