com.facebook.buck.java.abi.AnnotationValueMirror.java Source code

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Here is the source code for com.facebook.buck.java.abi.AnnotationValueMirror.java

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/*
 * Copyright 2015-present Facebook, Inc.
 *
 * 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.facebook.buck.java.abi;

import org.objectweb.asm.AnnotationVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;

import java.util.ArrayList;
import java.util.List;

import javax.annotation.Nullable;

class AnnotationValueMirror extends AnnotationVisitor {
    @Nullable
    private final Object primitiveValue;
    @Nullable
    private final EnumMirror enumValue;
    @Nullable
    private final AnnotationMirror annotationValue;
    @Nullable
    private final List<AnnotationValueMirror> arrayValue;

    public static AnnotationValueMirror forArray() {
        return new AnnotationValueMirror();
    }

    public static AnnotationValueMirror forAnnotation(AnnotationMirror annotation) {
        return new AnnotationValueMirror(annotation);
    }

    public static AnnotationValueMirror forEnum(String desc, String value) {
        return new AnnotationValueMirror(new EnumMirror(desc, value));
    }

    public static AnnotationValueMirror forPrimitive(Object value) {
        return new AnnotationValueMirror(value);
    }

    private AnnotationValueMirror(Object primitiveValue) {
        super(Opcodes.ASM5);
        this.primitiveValue = primitiveValue;
        this.enumValue = null;
        this.annotationValue = null;
        this.arrayValue = null;
    }

    private AnnotationValueMirror(EnumMirror enumValue) {
        super(Opcodes.ASM5);
        this.primitiveValue = null;
        this.enumValue = enumValue;
        this.annotationValue = null;
        this.arrayValue = null;
    }

    private AnnotationValueMirror(AnnotationMirror annotationValue) {
        super(Opcodes.ASM5);
        this.primitiveValue = null;
        this.enumValue = null;
        this.annotationValue = annotationValue;
        this.arrayValue = null;
    }

    private AnnotationValueMirror() {
        super(Opcodes.ASM5);
        this.primitiveValue = null;
        this.enumValue = null;
        this.annotationValue = null;
        this.arrayValue = new ArrayList<>();
    }

    public void accept(@Nullable String name, AnnotationVisitor visitor) {
        if (primitiveValue != null) {
            visitor.visit(name, primitiveValue);
        } else if (enumValue != null) {
            visitor.visitEnum(name, enumValue.desc, enumValue.value);
        } else if (annotationValue != null) {
            annotationValue.appendTo(visitor, name);
        } else if (arrayValue != null) {
            AnnotationVisitor arrayVisitor = visitor.visitArray(name);

            for (AnnotationValueMirror element : arrayValue) {
                element.accept(null, arrayVisitor);
            }

            arrayVisitor.visitEnd();
        }
    }

    @Override
    public AnnotationVisitor visitArray(String name) {
        throw new AssertionError("Annotation values cannot be nested arrays.");
    }

    @Override
    public void visit(@Nullable String name, Object value) {
        if (arrayValue == null) {
            throw new AssertionError("Calling visit makes no sense on a non-array AnnotationValue.");
        }
        if (!(value instanceof String) && !(value instanceof Type)) {
            throw new AssertionError("ASM is expected to provide primitive arrays as simple values.");
        }

        arrayValue.add(AnnotationValueMirror.forPrimitive(value));
    }

    @Override
    public void visitEnum(@Nullable String name, String desc, String value) {
        if (arrayValue == null) {
            throw new AssertionError("Calling visitEnum makes no sense on a non-array AnnotationValue.");
        }
        if (name != null) {
            throw new AssertionError("Expected name == null");
        }

        arrayValue.add(AnnotationValueMirror.forEnum(desc, value));
    }

    @Override
    public AnnotationVisitor visitAnnotation(@Nullable String name, String desc) {
        if (arrayValue == null) {
            throw new AssertionError("Calling visitAnnotation makes no sense on a non-array AnnotationValue.");
        }
        if (name != null) {
            throw new AssertionError("Expected name == null");
        }

        AnnotationMirror annotation = new AnnotationMirror(desc, true);
        arrayValue.add(AnnotationValueMirror.forAnnotation(annotation));
        return annotation; // Caller will call visit methods on this to provide the annotation args
    }
}