FieldOrMethod xref

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    1   /*
    2    * Copyright  2000-2004 The Apache Software Foundation
    3    *
    4    *  Licensed under the Apache License, Version 2.0 (the "License");
    5    *  you may not use this file except in compliance with the License.
    6    *  You may obtain a copy of the License at
    7    *
    8    *      http://www.apache.org/licenses/LICENSE-2.0
    9    *
    10   *  Unless required by applicable law or agreed to in writing, software
    11   *  distributed under the License is distributed on an "AS IS" BASIS,
    12   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   *  See the License for the specific language governing permissions and
    14   *  limitations under the License.
    15   *
    16   */
    17  package org.apache.bcel.generic;
    18
    19  import org.apache.bcel.classfile.ConstantCP;
    20  import org.apache.bcel.classfile.ConstantNameAndType;
    21  import org.apache.bcel.classfile.ConstantPool;
    22  import org.apache.bcel.classfile.ConstantUtf8;
    23
    24  /***
    25   * Super class for InvokeInstruction and FieldInstruction, since they have
    26   * some methods in common!
    27   *
    28   * @version $Id: FieldOrMethod.java 386056 2006-03-15 11:31:56Z tcurdt $
    29   * @author  <A HREF="mailto:m.dahm@gmx.de">M. Dahm</A>
    30   */
    31  public abstract class FieldOrMethod extends CPInstruction implements LoadClass {
    32
    33      /***
    34       * Empty constructor needed for the Class.newInstance() statement in
    35       * Instruction.readInstruction(). Not to be used otherwise.
    36       */
    37      FieldOrMethod() {
    38      }
    39
    40
    41      /***
    42       * @param index to constant pool
    43       */
    44      protected FieldOrMethod(short opcode, int index) {
    45          super(opcode, index);
    46      }
    47
    48
    49      /*** @return signature of referenced method/field.
    50       */
    51      public String getSignature( ConstantPoolGen cpg ) {
    52          ConstantPool cp = cpg.getConstantPool();
    53          ConstantCP cmr = (ConstantCP) cp.getConstant(index);
    54          ConstantNameAndType cnat = (ConstantNameAndType) cp.getConstant(cmr.getNameAndTypeIndex());
    55          return ((ConstantUtf8) cp.getConstant(cnat.getSignatureIndex())).getBytes();
    56      }
    57
    58
    59      /*** @return name of referenced method/field.
    60       */
    61      public String getName( ConstantPoolGen cpg ) {
    62          ConstantPool cp = cpg.getConstantPool();
    63          ConstantCP cmr = (ConstantCP) cp.getConstant(index);
    64          ConstantNameAndType cnat = (ConstantNameAndType) cp.getConstant(cmr.getNameAndTypeIndex());
    65          return ((ConstantUtf8) cp.getConstant(cnat.getNameIndex())).getBytes();
    66      }
    67
    68
    69      /*** @return name of the referenced class/interface
    70       *  @deprecated If the instruction references an array class,
    71       *    this method will return "java.lang.Object".
    72       *    For code generated by Java 1.5, this answer is
    73       *    sometimes wrong (e.g., if the "clone()" method is
    74       *    called on an array).  A better idea is to use
    75       *    the getReferenceType() method, which correctly distinguishes
    76       *    between class types and array types.
    77       */
    78      public String getClassName( ConstantPoolGen cpg ) {
    79          ConstantPool cp = cpg.getConstantPool();
    80          ConstantCP cmr = (ConstantCP) cp.getConstant(index);
    81          String className = cp.getConstantString(cmr.getClassIndex(),
    82                  org.apache.bcel.Constants.CONSTANT_Class);
    83          if (className.startsWith("[")) {
    84              // Turn array classes into java.lang.Object.
    85              return "java.lang.Object";
    86          }
    87          return className.replace('/', '.');
    88      }
    89
    90
    91      /*** @return type of the referenced class/interface
    92       * @deprecated If the instruction references an array class,
    93       *    the ObjectType returned will be invalid.  Use
    94       *    getReferenceType() instead.
    95       */
    96      public ObjectType getClassType( ConstantPoolGen cpg ) {
    97          return new ObjectType(getClassName(cpg));
    98      }
    99
    100
    101     /***
    102      * Return the reference type representing the class, interface,
    103      * or array class referenced by the instruction.
    104      * @param cpg the ConstantPoolGen used to create the instruction
    105      * @return an ObjectType (if the referenced class type is a class
    106      *   or interface), or an ArrayType (if the referenced class
    107      *   type is an array class)
    108      */
    109     public ReferenceType getReferenceType( ConstantPoolGen cpg ) {
    110         ConstantPool cp = cpg.getConstantPool();
    111         ConstantCP cmr = (ConstantCP) cp.getConstant(index);
    112         String className = cp.getConstantString(cmr.getClassIndex(),
    113                 org.apache.bcel.Constants.CONSTANT_Class);
    114         if (className.startsWith("[")) {
    115             return (ArrayType) Type.getType(className);
    116         } else {
    117             className = className.replace('/', '.');
    118             return new ObjectType(className);
    119         }
    120     }
    121
    122
    123     /*** @return type of the referenced class/interface
    124      */
    125     public ObjectType getLoadClassType( ConstantPoolGen cpg ) {
    126         return getClassType(cpg);
    127     }
    128 }