1 /*

     2  * Copyright (c) 2009, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 package com.sun.tools.javap;

    27 

    28 import com.sun.tools.classfile.Code_attribute;

    29 import com.sun.tools.classfile.Code_attribute.Exception_data;

    30 import com.sun.tools.classfile.Instruction;

    31 import java.util.ArrayList;

    32 import java.util.HashMap;

    33 import java.util.List;

    34 import java.util.ListIterator;

    35 import java.util.Map;

    36 

    37 /**

    38  * Annotate instructions with details about try blocks.

    39  *

    40  *  <p><b>This is NOT part of any supported API.

    41  *  If you write code that depends on this, you do so at your own risk.

    42  *  This code and its internal interfaces are subject to change or

    43  *  deletion without notice.</b>

    44  */

    45 public class TryBlockWriter extends InstructionDetailWriter {

    46     public enum NoteKind {

    47         START("try") {

    48             public boolean match(Exception_data entry, int pc) {

    49                 return (pc == entry.start_pc);

    50             }

    51         },

    52         END("end try") {

    53             public boolean match(Exception_data entry, int pc) {

    54                 return (pc == entry.end_pc);

    55             }

    56         },

    57         HANDLER("catch") {

    58             public boolean match(Exception_data entry, int pc) {

    59                 return (pc == entry.handler_pc);

    60             }

    61         };

    62         NoteKind(String text) {

    63             this.text = text;

    64         }

    65         public abstract boolean match(Exception_data entry, int pc);

    66         public final String text;

    67     }

    68 

    69     static TryBlockWriter instance(Context context) {

    70         TryBlockWriter instance = context.get(TryBlockWriter.class);

    71         if (instance == null)

    72             instance = new TryBlockWriter(context);

    73         return instance;

    74     }

    75 

    76     protected TryBlockWriter(Context context) {

    77         super(context);

    78         context.put(TryBlockWriter.class, this);

    79         constantWriter = ConstantWriter.instance(context);

    80     }

    81 

    82     public void reset(Code_attribute attr) {

    83         indexMap = new HashMap<>();

    84         pcMap = new HashMap<>();

    85         for (int i = 0; i < attr.exception_table.length; i++) {

    86             Exception_data entry = attr.exception_table[i];

    87             indexMap.put(entry, i);

    88             put(entry.start_pc, entry);

    89             put(entry.end_pc, entry);

    90             put(entry.handler_pc, entry);

    91         }

    92     }

    93 

    94     public void writeDetails(Instruction instr) {

    95         writeTrys(instr, NoteKind.END);

    96         writeTrys(instr, NoteKind.START);

    97         writeTrys(instr, NoteKind.HANDLER);

    98     }

    99 

   100     public void writeTrys(Instruction instr, NoteKind kind) {

   101         String indent = space(2); // get from Options?

   102         int pc = instr.getPC();

   103         List<Exception_data> entries = pcMap.get(pc);

   104         if (entries != null) {

   105             for (ListIterator<Exception_data> iter =

   106                     entries.listIterator(kind == NoteKind.END ? entries.size() : 0);

   107                     kind == NoteKind.END ? iter.hasPrevious() : iter.hasNext() ; ) {

   108                 Exception_data entry =

   109                         kind == NoteKind.END ? iter.previous() : iter.next();

   110                 if (kind.match(entry, pc)) {

   111                     print(indent);

   112                     print(kind.text);

   113                     print("[");

   114                     print(indexMap.get(entry));

   115                     print("] ");

   116                     if (entry.catch_type == 0)

   117                         print("finally");

   118                     else {

   119                         print("#" + entry.catch_type);

   120                         print(" // ");

   121                         constantWriter.write(entry.catch_type);

   122                     }

   123                     println();

   124                 }

   125             }

   126         }

   127     }

   128 

   129     private void put(int pc, Exception_data entry) {

   130         List<Exception_data> list = pcMap.get(pc);

   131         if (list == null) {

   132             list = new ArrayList<>();

   133             pcMap.put(pc, list);

   134         }

   135         if (!list.contains(entry))

   136             list.add(entry);

   137     }

   138 

   139     private Map<Integer, List<Exception_data>> pcMap;

   140     private Map<Exception_data, Integer> indexMap;

   141     private ConstantWriter constantWriter;

   142 }