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ProGuardCORE is a free library to read, analyze, modify, and write Java class files.

There is a newer version: 9.1.6

/*
 * ProGuardCORE -- library to process Java bytecode.
 *
 * Copyright (c) 2002-2020 Guardsquare NV
 *
 * 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 proguard.classfile.util;

import proguard.classfile.*;
import proguard.classfile.constant.*;
import proguard.classfile.constant.visitor.ConstantVisitor;

/**
 * This {@link ConstantVisitor} initializes any class references of all string constants it visits.
 * More specifically, it fills out the references of string constant pool entries that happen to
 * refer to a class in the program class pool or in the library class pool.
 *
 * @author Eric Lafortune
 */
public class StringReferenceInitializer implements ConstantVisitor {
  private final ClassPool programClassPool;
  private final ClassPool libraryClassPool;

  /** Creates a new StringReferenceInitializer. */
  public StringReferenceInitializer(ClassPool programClassPool, ClassPool libraryClassPool) {
    this.programClassPool = programClassPool;
    this.libraryClassPool = libraryClassPool;
  }

  // Implementations for ConstantVisitor.

  public void visitAnyConstant(Clazz clazz, Constant constant) {}

  public void visitStringConstant(Clazz clazz, StringConstant stringConstant) {
    if (stringConstant.referencedClass == null) {
      // See if we can find the referenced class.
      stringConstant.referencedClass =
          findClass(
              ClassUtil.internalClassName(
                  ClassUtil.externalBaseType(stringConstant.getString(clazz))));
    }
  }

  // Small utility methods.

  /**
   * Returns the class with the given name, either for the program class pool or from the library
   * class pool, or null if it can't be found.
   */
  private Clazz findClass(String name) {
    // First look for the class in the program class pool.
    Clazz clazz = programClassPool.getClass(name);

    // Otherwise look for the class in the library class pool.
    if (clazz == null) {
      clazz = libraryClassPool.getClass(name);
    }

    return clazz;
  }
}