net.orfjackal.retrolambda.requirenonnull.RequireNonNull Maven / Gradle / Ivy
// Copyright 2016 The Retrolambda Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package net.orfjackal.retrolambda.requirenonnull;
import org.objectweb.asm.*;
/**
* Rewrites calls to {@code Objects.requireNonNull}, which is only available in JDK 7 and above.
*
* Starting in JDK 9, javac uses {@code requireNonNull} for synthetic null-checks
* (see JDK-8074306).
*/
public class RequireNonNull extends ClassVisitor {
public RequireNonNull(ClassVisitor next) {
super(Opcodes.ASM5, next);
}
@Override
public MethodVisitor visitMethod(
int access, String name, String desc, String signature, String[] exceptions) {
MethodVisitor next = super.visitMethod(access, name, desc, signature, exceptions);
return new MethodVisitor(Opcodes.ASM5, next) {
@Override
public void visitMethodInsn(
int opcode, String owner, String name, String desc, boolean itf) {
if (opcode == Opcodes.INVOKESTATIC
&& owner.equals("java/util/Objects")
&& name.equals("requireNonNull")
&& desc.equals("(Ljava/lang/Object;)Ljava/lang/Object;")) {
super.visitInsn(Opcodes.DUP);
super.visitMethodInsn(
Opcodes.INVOKEVIRTUAL,
"java/lang/Object",
"getClass",
"()Ljava/lang/Class;",
false);
super.visitInsn(Opcodes.POP);
} else {
super.visitMethodInsn(opcode, owner, name, desc, itf);
}
}
};
}
}