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.SimpleFunctionDescriptor;
028 import org.jetbrains.jet.lang.psi.JetFile;
029 import org.jetbrains.jet.lang.psi.JetPsiUtil;
030 import org.jetbrains.jet.lang.resolve.DescriptorUtils;
031 import org.jetbrains.jet.lang.resolve.java.JvmClassName;
032 import org.jetbrains.jet.lang.resolve.java.PackageClassUtils;
033 import org.jetbrains.jet.lang.resolve.java.descriptor.JavaClassDescriptor;
034 import org.jetbrains.jet.lang.resolve.java.sam.SingleAbstractMethodUtils;
035 import org.jetbrains.jet.lang.resolve.name.FqName;
036 import org.jetbrains.jet.lang.resolve.name.Name;
037 import org.jetbrains.jet.lang.types.JetType;
038
039 import static org.jetbrains.asm4.Opcodes.*;
040 import static org.jetbrains.jet.codegen.AsmUtil.NO_FLAG_PACKAGE_PRIVATE;
041 import static org.jetbrains.jet.lang.resolve.java.AsmTypeConstants.OBJECT_TYPE;
042
043 public class SamWrapperCodegen extends ParentCodegenAwareImpl {
044 private static final String FUNCTION_FIELD_NAME = "function";
045
046 @NotNull private final JavaClassDescriptor samInterface;
047
048 public SamWrapperCodegen(
049 @NotNull GenerationState state,
050 @NotNull JavaClassDescriptor samInterface,
051 @Nullable MemberCodegen parentCodegen
052 ) {
053 super(state, parentCodegen);
054 this.samInterface = samInterface;
055 }
056
057 public Type genWrapper(@NotNull JetFile file) {
058 // Name for generated class, in form of whatever$1
059 Type asmType = Type.getObjectType(getWrapperName(file));
060
061 // e.g. (T, T) -> Int
062 JetType functionType = samInterface.getFunctionTypeForSamInterface();
063 assert functionType != null : samInterface.toString();
064 // e.g. compare(T, T)
065 SimpleFunctionDescriptor interfaceFunction = SingleAbstractMethodUtils.getAbstractMethodOfSamInterface(samInterface);
066
067 ClassBuilder cv = state.getFactory().newVisitor(asmType, file);
068 cv.defineClass(file,
069 V1_6,
070 ACC_FINAL,
071 asmType.getInternalName(),
072 null,
073 OBJECT_TYPE.getInternalName(),
074 new String[]{ typeMapper.mapType(samInterface).getInternalName() }
075 );
076 cv.visitSource(file.getName(), null);
077
078 // e.g. ASM type for Function2
079 Type functionAsmType = state.getTypeMapper().mapType(functionType);
080
081 cv.newField(null,
082 ACC_SYNTHETIC | ACC_PRIVATE | ACC_FINAL,
083 FUNCTION_FIELD_NAME,
084 functionAsmType.getDescriptor(),
085 null,
086 null);
087
088 generateConstructor(asmType, functionAsmType, cv);
089 generateMethod(asmType, functionAsmType, cv, interfaceFunction, functionType);
090
091 cv.done();
092
093 return asmType;
094 }
095
096 private void generateConstructor(Type ownerType, Type functionType, ClassBuilder cv) {
097 MethodVisitor mv = cv.newMethod(null, NO_FLAG_PACKAGE_PRIVATE, "<init>", Type.getMethodDescriptor(Type.VOID_TYPE, functionType), null, null);
098
099 if (state.getClassBuilderMode() == ClassBuilderMode.FULL) {
100 mv.visitCode();
101 InstructionAdapter iv = new InstructionAdapter(mv);
102
103 // super constructor
104 iv.load(0, OBJECT_TYPE);
105 iv.invokespecial(OBJECT_TYPE.getInternalName(), "<init>", "()V");
106
107 // save parameter to field
108 iv.load(0, OBJECT_TYPE);
109 iv.load(1, functionType);
110 iv.putfield(ownerType.getInternalName(), FUNCTION_FIELD_NAME, functionType.getDescriptor());
111
112 iv.visitInsn(RETURN);
113 FunctionCodegen.endVisit(iv, "constructor of SAM wrapper", null);
114 }
115 }
116
117 private void generateMethod(
118 Type ownerType,
119 Type functionType,
120 ClassBuilder cv,
121 SimpleFunctionDescriptor interfaceFunction,
122 JetType functionJetType
123 ) {
124
125 // using static context to avoid creating ClassDescriptor and everything else
126 FunctionCodegen codegen = new FunctionCodegen(CodegenContext.STATIC, cv, state, getParentCodegen());
127
128 FunctionDescriptor invokeFunction = functionJetType.getMemberScope()
129 .getFunctions(Name.identifier("invoke")).iterator().next().getOriginal();
130 StackValue functionField = StackValue.field(functionType, ownerType, FUNCTION_FIELD_NAME, false);
131 codegen.genDelegate(interfaceFunction, invokeFunction, functionField);
132 }
133
134 private String getWrapperName(@NotNull JetFile containingFile) {
135 FqName packageClassFqName = PackageClassUtils.getPackageClassFqName(JetPsiUtil.getFQName(containingFile));
136 String packageInternalName = JvmClassName.byFqNameWithoutInnerClasses(packageClassFqName).getInternalName();
137 return packageInternalName + "$sam$" + samInterface.getName().asString() + "$" +
138 Integer.toHexString(CodegenUtil.getPathHashCode(containingFile.getVirtualFile()) * 31 + DescriptorUtils.getFqNameSafe(
139 samInterface).hashCode());
140 }
141 }