view agent/src/share/classes/sun/jvm/hotspot/oops/FieldType.java @ 6169:cfa2c82f4c04

7175133: jinfo failed to get system properties after 6924259 Summary: String offset and count fields as fix of 6924259 were removed, and become optional. SA still use offset and count fields to read String contents and failed. Fix if they exist, use them other then use value field only to read, this keeps consistent with the changes in 6924259. Reviewed-by: dholmes, mikael Contributed-by: yumin.qi@oracle.com
author minqi
date Fri, 22 Jun 2012 15:35:30 -0700
parents f6f3bb0ee072
children
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/*
 * Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

package sun.jvm.hotspot.oops;

import java.io.*;
import sun.jvm.hotspot.runtime.BasicType;
import sun.jvm.hotspot.utilities.*;

public class FieldType {

  private Symbol signature;
  private char   first;

  public FieldType(Symbol signature) {
    this.signature = signature;
    this.first     = (char) signature.getByteAt(0);
    if (Assert.ASSERTS_ENABLED) {
       switch (this.first) {
       case 'B':
       case 'C':
       case 'D':
       case 'F':
       case 'I':
       case 'J':
       case 'S':
       case 'Z':
       case 'L':
       case '[':
           break;   // Ok. signature char known
       default:
         Assert.that(false, "Unknown char in field signature \"" + signature.asString() + "\": " + this.first);
       }
    }
  }

  public boolean isOop()     { return isObject() || isArray(); }
  public boolean isByte()    { return first == 'B'; }
  public boolean isChar()    { return first == 'C'; }
  public boolean isDouble()  { return first == 'D'; }
  public boolean isFloat()   { return first == 'F'; }
  public boolean isInt()     { return first == 'I'; }
  public boolean isLong()    { return first == 'J'; }
  public boolean isShort()   { return first == 'S'; }
  public boolean isBoolean() { return first == 'Z'; }
  public boolean isObject()  { return first == 'L'; }
  public boolean isArray()   { return first == '['; }

  public Symbol getSignature() { return signature; }

  public static class ArrayInfo {
    private int dimension;
    private int elementBasicType; // See BasicType.java
    // FIXME: consider adding name of element class

    public ArrayInfo(int dimension, int elementBasicType) {
      this.dimension = dimension;
      this.elementBasicType = elementBasicType;
    }

    public int dimension()        { return dimension; }
    /** See BasicType.java */
    public int elementBasicType() { return elementBasicType; }
  }

  /** Only valid for T_ARRAY; throws unspecified exception otherwise */
  public ArrayInfo getArrayInfo() {
    int index = 1;
    int dim   = 1;
    index = skipOptionalSize(signature, index);
    while (signature.getByteAt(index) == '[') {
      index++;
      dim++;
      skipOptionalSize(signature, index);
    }
    int elementType = BasicType.charToType((char) signature.getByteAt(index));
    return new ArrayInfo(dim, elementType);
  }

  private int skipOptionalSize(Symbol sig, int index) {
    byte c = sig.getByteAt(index);
    while (c >= '0' && c <= '9') {
      ++index;
      c = sig.getByteAt(index);
    }
    return index;
  }
}