Package org.apache.bcel.classfile

Source Code of org.apache.bcel.classfile.FieldOrMethod

/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements.  See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.bcel.classfile;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.bcel.Constants;
import org.apache.bcel.classfile.Attribute;
import org.apache.bcel.classfile.Signature;

/**
* Abstract super class for fields and methods.
*
* @version $Id: FieldOrMethod.java 1149459 2011-07-22 04:34:27Z dbrosius $
* @author  <A HREF="mailto:m.dahm@gmx.de">M. Dahm</A>
*/
public abstract class FieldOrMethod extends AccessFlags implements Cloneable, Node {

    private static final long serialVersionUID = -1833306330869469714L;
    protected int name_index; // Points to field name in constant pool
    protected int signature_index; // Points to encoded signature
    protected int attributes_count; // No. of attributes
    protected Attribute[] attributes; // Collection of attributes
    protected AnnotationEntry[] annotationEntries; // annotations defined on the field or method
    protected ConstantPool constant_pool;

    private String signatureAttributeString = null;
    private boolean searchedForSignatureAttribute = false;
   

    // Annotations are collected from certain attributes, don't do it more than necessary!
    private boolean annotationsOutOfDate = true;

    FieldOrMethod() {
    }


    /**
     * Initialize from another object. Note that both objects use the same
     * references (shallow copy). Use clone() for a physical copy.
     */
    protected FieldOrMethod(FieldOrMethod c) {
        this(c.getAccessFlags(), c.getNameIndex(), c.getSignatureIndex(), c.getAttributes(), c
                .getConstantPool());
    }


    /**
     * Construct object from file stream.
     * @param file Input stream
     * @throws IOException
     * @throws ClassFormatException
     */
    protected FieldOrMethod(DataInputStream file, ConstantPool constant_pool) throws IOException,
            ClassFormatException {
        this(file.readUnsignedShort(), file.readUnsignedShort(), file.readUnsignedShort(), null,
                constant_pool);
        attributes_count = file.readUnsignedShort();
        attributes = new Attribute[attributes_count];
        for (int i = 0; i < attributes_count; i++) {
            attributes[i] = Attribute.readAttribute(file, constant_pool);
        }
    }


    /**
     * @param access_flags Access rights of method
     * @param name_index Points to field name in constant pool
     * @param signature_index Points to encoded signature
     * @param attributes Collection of attributes
     * @param constant_pool Array of constants
     */
    protected FieldOrMethod(int access_flags, int name_index, int signature_index,
            Attribute[] attributes, ConstantPool constant_pool) {
        this.access_flags = access_flags;
        this.name_index = name_index;
        this.signature_index = signature_index;
        this.constant_pool = constant_pool;
        setAttributes(attributes);
    }


    /**
     * Dump object to file stream on binary format.
     *
     * @param file Output file stream
     * @throws IOException
     */
    public final void dump( DataOutputStream file ) throws IOException {
        file.writeShort(access_flags);
        file.writeShort(name_index);
        file.writeShort(signature_index);
        file.writeShort(attributes_count);
        for (int i = 0; i < attributes_count; i++) {
            attributes[i].dump(file);
        }
    }


    /**
     * @return Collection of object attributes.
     */
    public final Attribute[] getAttributes() {
        return attributes;
    }


    /**
     * @param attributes Collection of object attributes.
     */
    public final void setAttributes( Attribute[] attributes ) {
        this.attributes = attributes;
        attributes_count = (attributes == null) ? 0 : attributes.length;
    }


    /**
     * @return Constant pool used by this object.
     */
    public final ConstantPool getConstantPool() {
        return constant_pool;
    }


    /**
     * @param constant_pool Constant pool to be used for this object.
     */
    public final void setConstantPool( ConstantPool constant_pool ) {
        this.constant_pool = constant_pool;
    }


    /**
     * @return Index in constant pool of object's name.
     */
    public final int getNameIndex() {
        return name_index;
    }


    /**
     * @param name_index Index in constant pool of object's name.
     */
    public final void setNameIndex( int name_index ) {
        this.name_index = name_index;
    }


    /**
     * @return Index in constant pool of field signature.
     */
    public final int getSignatureIndex() {
        return signature_index;
    }


    /**
     * @param signature_index Index in constant pool of field signature.
     */
    public final void setSignatureIndex( int signature_index ) {
        this.signature_index = signature_index;
    }


    /**
     * @return Name of object, i.e., method name or field name
     */
    public final String getName() {
        ConstantUtf8 c;
        c = (ConstantUtf8) constant_pool.getConstant(name_index, Constants.CONSTANT_Utf8);
        return c.getBytes();
    }


    /**
     * @return String representation of object's type signature (java style)
     */
    public final String getSignature() {
        ConstantUtf8 c;
        c = (ConstantUtf8) constant_pool.getConstant(signature_index, Constants.CONSTANT_Utf8);
        return c.getBytes();
    }


    /**
     * @return deep copy of this field
     */
    protected FieldOrMethod copy_( ConstantPool _constant_pool ) {
      FieldOrMethod c = null;

        try {
          c = (FieldOrMethod)clone();
        } catch(CloneNotSupportedException e) {}

        c.constant_pool    = constant_pool;
        c.attributes       = new Attribute[attributes_count];

        for(int i=0; i < attributes_count; i++)
          c.attributes[i] = attributes[i].copy(constant_pool);

        return c;
    }
   
    /**
   * Ensure we have unpacked any attributes that contain annotations.
   * We don't remove these annotation attributes from the attributes list, they
   * remain there.
   */
  private void ensureAnnotationsUpToDate()
  {
    if (annotationsOutOfDate)
    {
      // Find attributes that contain annotation data
      Attribute[] attrs = getAttributes();
      List<AnnotationEntry> accumulatedAnnotations = new ArrayList<AnnotationEntry>();
      for (int i = 0; i < attrs.length; i++)
      {
        Attribute attribute = attrs[i];
        if (attribute instanceof Annotations)
        {
          Annotations annotations = (Annotations) attribute;
          for (int j = 0; j < annotations.getAnnotationEntries().length; j++)
          {
            accumulatedAnnotations.add(annotations
                .getAnnotationEntries()[j]);
          }
        }
      }
      annotationEntries = accumulatedAnnotations
          .toArray(new AnnotationEntry[accumulatedAnnotations.size()]);
      annotationsOutOfDate = false;
    }
  }

  public AnnotationEntry[] getAnnotationEntries()
  {
    ensureAnnotationsUpToDate();
    return annotationEntries;
  }

  public void addAnnotationEntry(AnnotationEntry a)
  {
    ensureAnnotationsUpToDate();
    int len = annotationEntries.length;
    AnnotationEntry[] newAnnotations = new AnnotationEntry[len + 1];
    System.arraycopy(annotationEntries, 0, newAnnotations, 0, len);
    newAnnotations[len] = a;
    annotationEntries = newAnnotations;
  }

  /**
   * Hunts for a signature attribute on the member and returns its contents.  So where the 'regular' signature
   * may be (Ljava/util/Vector;)V the signature attribute may in fact say 'Ljava/lang/Vector<Ljava/lang/String>;'
   * Coded for performance - searches for the attribute only when requested - only searches for it once.
   */
  public final String getGenericSignature()
  {
    if (!searchedForSignatureAttribute)
    {
      boolean found = false;
      for (int i = 0; !found && i < attributes_count; i++)
      {
        if (attributes[i] instanceof Signature)
        {
          signatureAttributeString = ((Signature) attributes[i])
              .getSignature();
          found = true;
        }
      }
      searchedForSignatureAttribute = true;
    }
    return signatureAttributeString;
  }
}
TOP

Related Classes of org.apache.bcel.classfile.FieldOrMethod

TOP
Copyright © 2018 www.massapi.com. All rights reserved.
All source code are property of their respective owners. Java is a trademark of Sun Microsystems, Inc and owned by ORACLE Inc. Contact coftware#gmail.com.