unplugged-system/tools/platform-compat/java/com/android/annotationvisitor/RepeatedAnnotationHandler.java

75 lines
2.8 KiB
Java

/*
* Copyright (C) 2021 The Android Open Source Project
*
* 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 com.android.annotationvisitor;
import com.google.common.base.Preconditions;
import org.apache.bcel.classfile.AnnotationElementValue;
import org.apache.bcel.classfile.AnnotationEntry;
import org.apache.bcel.classfile.ArrayElementValue;
import org.apache.bcel.classfile.ElementValue;
import org.apache.bcel.classfile.ElementValuePair;
/**
* Handles a repeated annotation container.
*
* <p>The enclosed annotations are passed to the {@link #mWrappedHandler}.
*/
public class RepeatedAnnotationHandler extends AnnotationHandler {
private static final String VALUE = "value";
private final AnnotationHandler mWrappedHandler;
private final String mInnerAnnotationName;
public RepeatedAnnotationHandler(String innerAnnotationName, AnnotationHandler wrappedHandler) {
mWrappedHandler = wrappedHandler;
mInnerAnnotationName = innerAnnotationName;
}
@Override
public void handleAnnotation(AnnotationEntry annotation, AnnotationContext context) {
// Verify that the annotation has the form we expect
ElementValuePair value = findValue(annotation);
if (value == null) {
context.reportError("No value found on %s", annotation.getAnnotationType());
return;
}
Preconditions.checkArgument(value.getValue() instanceof ArrayElementValue);
ArrayElementValue array = (ArrayElementValue) value.getValue();
// call wrapped handler on each enclosed annotation:
for (ElementValue v : array.getElementValuesArray()) {
Preconditions.checkArgument(v instanceof AnnotationElementValue);
AnnotationElementValue aev = (AnnotationElementValue) v;
Preconditions.checkArgument(
aev.getAnnotationEntry().getAnnotationType().equals(mInnerAnnotationName));
mWrappedHandler.handleAnnotation(aev.getAnnotationEntry(), context);
}
}
private ElementValuePair findValue(AnnotationEntry a) {
for (ElementValuePair property : a.getElementValuePairs()) {
if (property.getNameString().equals(VALUE)) {
return property;
}
}
// not found
return null;
}
}