001 /*
002 * Copyright 2010-2013 JetBrains s.r.o.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017 package org.jetbrains.jet.codegen;
018
019 import org.jetbrains.annotations.NotNull;
020 import org.jetbrains.annotations.Nullable;
021 import org.jetbrains.asm4.MethodVisitor;
022 import org.jetbrains.asm4.Type;
023 import org.jetbrains.asm4.commons.InstructionAdapter;
024 import org.jetbrains.jet.codegen.context.CodegenContext;
025 import org.jetbrains.jet.codegen.state.GenerationState;
026 import org.jetbrains.jet.lang.descriptors.FunctionDescriptor;
027 import org.jetbrains.jet.lang.descriptors.NamespaceDescriptor;
028 import org.jetbrains.jet.lang.descriptors.SimpleFunctionDescriptor;
029 import org.jetbrains.jet.lang.psi.JetFile;
030 import org.jetbrains.jet.lang.resolve.BindingContext;
031 import org.jetbrains.jet.lang.resolve.DescriptorUtils;
032 import org.jetbrains.jet.lang.resolve.java.JvmClassName;
033 import org.jetbrains.jet.lang.resolve.java.PackageClassUtils;
034 import org.jetbrains.jet.lang.resolve.java.descriptor.ClassDescriptorFromJvmBytecode;
035 import org.jetbrains.jet.lang.resolve.java.sam.SingleAbstractMethodUtils;
036 import org.jetbrains.jet.lang.resolve.name.FqName;
037 import org.jetbrains.jet.lang.resolve.name.Name;
038 import org.jetbrains.jet.lang.types.JetType;
039
040 import static org.jetbrains.asm4.Opcodes.*;
041 import static org.jetbrains.jet.codegen.AsmUtil.NO_FLAG_PACKAGE_PRIVATE;
042 import static org.jetbrains.jet.lang.resolve.java.AsmTypeConstants.OBJECT_TYPE;
043
044 public class SamWrapperCodegen extends ParentCodegenAwareImpl {
045 private static final String FUNCTION_FIELD_NAME = "function";
046
047 @NotNull private final ClassDescriptorFromJvmBytecode samInterface;
048
049 public SamWrapperCodegen(
050 @NotNull GenerationState state,
051 @NotNull ClassDescriptorFromJvmBytecode samInterface,
052 @Nullable MemberCodegen parentCodegen
053 ) {
054 super(state, parentCodegen);
055 this.samInterface = samInterface;
056 }
057
058 public Type genWrapper(@NotNull JetFile file) {
059 // Name for generated class, in form of whatever$1
060 Type asmType = Type.getObjectType(getWrapperName(file));
061
062 // e.g. (T, T) -> Int
063 JetType functionType = samInterface.getFunctionTypeForSamInterface();
064 assert functionType != null : samInterface.toString();
065 // e.g. compare(T, T)
066 SimpleFunctionDescriptor interfaceFunction = SingleAbstractMethodUtils.getAbstractMethodOfSamInterface(samInterface);
067
068 ClassBuilder cv = state.getFactory().newVisitor(asmType, file);
069 cv.defineClass(file,
070 V1_6,
071 ACC_FINAL,
072 asmType.getInternalName(),
073 null,
074 OBJECT_TYPE.getInternalName(),
075 new String[]{ typeMapper.mapType(samInterface).getInternalName() }
076 );
077 cv.visitSource(file.getName(), null);
078
079 // e.g. ASM type for Function2
080 Type functionAsmType = state.getTypeMapper().mapType(functionType);
081
082 cv.newField(null,
083 ACC_SYNTHETIC | ACC_PRIVATE | ACC_FINAL,
084 FUNCTION_FIELD_NAME,
085 functionAsmType.getDescriptor(),
086 null,
087 null);
088
089 generateConstructor(asmType, functionAsmType, cv);
090 generateMethod(asmType, functionAsmType, cv, interfaceFunction, functionType);
091
092 cv.done();
093
094 return asmType;
095 }
096
097 private void generateConstructor(Type ownerType, Type functionType, ClassBuilder cv) {
098 MethodVisitor mv = cv.newMethod(null, NO_FLAG_PACKAGE_PRIVATE, "<init>", Type.getMethodDescriptor(Type.VOID_TYPE, functionType), null, null);
099
100 if (state.getClassBuilderMode() == ClassBuilderMode.FULL) {
101 mv.visitCode();
102 InstructionAdapter iv = new InstructionAdapter(mv);
103
104 // super constructor
105 iv.load(0, OBJECT_TYPE);
106 iv.invokespecial(OBJECT_TYPE.getInternalName(), "<init>", "()V");
107
108 // save parameter to field
109 iv.load(0, OBJECT_TYPE);
110 iv.load(1, functionType);
111 iv.putfield(ownerType.getInternalName(), FUNCTION_FIELD_NAME, functionType.getDescriptor());
112
113 iv.visitInsn(RETURN);
114 FunctionCodegen.endVisit(iv, "constructor of SAM wrapper", null);
115 }
116 }
117
118 private void generateMethod(
119 Type ownerType,
120 Type functionType,
121 ClassBuilder cv,
122 SimpleFunctionDescriptor interfaceFunction,
123 JetType functionJetType
124 ) {
125
126 // using static context to avoid creating ClassDescriptor and everything else
127 FunctionCodegen codegen = new FunctionCodegen(CodegenContext.STATIC, cv, state, getParentCodegen());
128
129 FunctionDescriptor invokeFunction = functionJetType.getMemberScope()
130 .getFunctions(Name.identifier("invoke")).iterator().next().getOriginal();
131 StackValue functionField = StackValue.field(functionType, ownerType, FUNCTION_FIELD_NAME, false);
132 codegen.genDelegate(interfaceFunction, invokeFunction, functionField);
133 }
134
135 private String getWrapperName(@NotNull JetFile containingFile) {
136 NamespaceDescriptor namespace = state.getBindingContext().get(BindingContext.FILE_TO_NAMESPACE, containingFile);
137 assert namespace != null : "couldn't find namespace for file: " + containingFile.getVirtualFile();
138 FqName fqName = DescriptorUtils.getFQName(namespace).toSafe();
139 String packageInternalName = JvmClassName.byFqNameWithoutInnerClasses(
140 PackageClassUtils.getPackageClassFqName(fqName)).getInternalName();
141 return packageInternalName + "$sam$" + samInterface.getName().asString() + "$" +
142 Integer.toHexString(CodegenUtil.getPathHashCode(containingFile) * 31 + DescriptorUtils.getFQName(samInterface).hashCode());
143 }
144 }