instanceof()的源码在哪,我找半天没找到

Question

1.我在源文件src和api里面都找不到,这是怎么回事呢,还是说他属于哪个类呢?
2.一般api有两种搜索,一种是index,另一种是find 这两种分别是搜索什么呢?

Answer 1

/*

• Javassist, a Java-bytecode translator toolkit.
• Copyright (C) 1999- Shigeru Chiba. All Rights Reserved. *
• The contents of this file are subject to the Mozilla Public License Version
• 1.1 (the "License"); you may not use this file except in compliance with
• the License. Alternatively, the contents of this file may be used under
• the terms of the GNU Lesser General Public License Version 2.1 or later,
• or the Apache License Version 2.0. *
• Software distributed under the License is distributed on an "AS IS" basis,
• WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
• for the specific language governing rights and limitations under the
• License. */

package javassist.expr;

import javassist.*;
import javassist.bytecode.*;
import javassist.compiler.*;
import javassist.compiler.ast.ASTList;

/**

• Instanceof operator.
  /
  public class Instanceof extends Expr {
  /*

  • Undocumented constructor. Do not use; internal-use only. */ protected Instanceof(int pos, CodeIterator i, CtClass declaring, MethodInfo m) { super(pos, i, declaring, m); }

  /**

  • Returns the method or constructor containing the instanceof
  • expression represented by this object. */ public CtBehavior where() { return super.where(); }

  /**

  • Returns the line number of the source line containing the
  • instanceof expression. *
  • @return -1 if this information is not available. */ public int getLineNumber() { return super.getLineNumber(); }

  /**

  • Returns the source file containing the
  • instanceof expression. *
  • @return null if this information is not available. */ public String getFileName() { return super.getFileName(); }

  /**

  • Returns the CtClass object representing
  • the type name on the right hand side
  • of the instanceof operator. */ public CtClass getType() throws NotFoundException { ConstPool cp = getConstPool(); int pos = currentPos; int index = iterator.u16bitAt(pos + 1); String name = cp.getClassInfo(index); return thisClass.getClassPool().getCtClass(name); }

  /**

  • Returns the list of exceptions that the expression may throw.
  • This list includes both the exceptions that the try-catch statements
  • including the expression can catch and the exceptions that
  • the throws declaration allows the method to throw. */ public CtClass[] mayThrow() { return super.mayThrow(); }

  /**

  • Replaces the instanceof operator with the bytecode derived from
  • the given source text. *

  • $0 is available but the value is null. *

  • @param statement a Java statement except try-catch.
    */
    public void replace(String statement) throws CannotCompileException {
    thisClass.getClassFile(); // to call checkModify().
    ConstPool constPool = getConstPool();
    int pos = currentPos;
    int index = iterator.u16bitAt(pos + 1);

    Javac jc = new Javac(thisClass);
    ClassPool cp = thisClass.getClassPool();
    CodeAttribute ca = iterator.get();

    try {
    CtClass[] params
    = new CtClass[] { cp.get(javaLangObject) };
    CtClass retType = CtClass.booleanType;

    int paramVar = ca.getMaxLocals();
    jc.recordParams(javaLangObject, params, true, paramVar,
                    withinStatic());
    int retVar = jc.recordReturnType(retType, true);
    jc.recordProceed(new ProceedForInstanceof(index));
    
    // because $type is not the return type...
    jc.recordType(getType());
    
    /* Is $_ included in the source code?
     */
    checkResultValue(retType, statement);
    
    Bytecode bytecode = jc.getBytecode();
    storeStack(params, true, paramVar, bytecode);
    jc.recordLocalVariables(ca, pos);
    
    bytecode.addConstZero(retType);
    bytecode.addStore(retVar, retType);     // initialize $_
    
    jc.compileStmnt(statement);
    bytecode.addLoad(retVar, retType);
    
    replace0(pos, bytecode, 3);
    

    }
    catch (CompileError e) { throw new CannotCompileException(e); }
    catch (NotFoundException e) { throw new CannotCompileException(e); }
    catch (BadBytecode e) {
    throw new CannotCompileException("broken method");
    }
    }

  /* boolean $proceed(Object obj)
  */
  static class ProceedForInstanceof implements ProceedHandler {
  int index;

  ProceedForInstanceof(int i) {
      index = i;
  }
  
  public void doit(JvstCodeGen gen, Bytecode bytecode, ASTList args)
      throws CompileError
  {
      if (gen.getMethodArgsLength(args) != 1)
          throw new CompileError(Javac.proceedName
                  + "() cannot take more than one parameter "
                  + "for instanceof");
  
      gen.atMethodArgs(args, new int[1], new int[1], new String[1]);
      bytecode.addOpcode(Opcode.INSTANCEOF);
      bytecode.addIndex(index);
      gen.setType(CtClass.booleanType);
  }
  
  public void setReturnType(JvstTypeChecker c, ASTList args)
      throws CompileError
  {
      c.atMethodArgs(args, new int[1], new int[1], new String[1]);
      c.setType(CtClass.booleanType);
  }
  

  }
  }