diff src/com/go/trove/classfile/LineNumberTableAttr.java @ 0:3dc0c5604566

Initial checkin of blitz 2.0 fcs - no installer yet.
author Dan Creswell <dan.creswell@gmail.com>
date Sat, 21 Mar 2009 11:00:06 +0000
parents
children
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/com/go/trove/classfile/LineNumberTableAttr.java	Sat Mar 21 11:00:06 2009 +0000
@@ -0,0 +1,193 @@
+/* ====================================================================
+ * Trove - Copyright (c) 1997-2000 Walt Disney Internet Group
+ * ====================================================================
+ * The Tea Software License, Version 1.1
+ *
+ * Copyright (c) 2000 Walt Disney Internet Group. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. The end-user documentation included with the redistribution,
+ *    if any, must include the following acknowledgment:
+ *       "This product includes software developed by the
+ *        Walt Disney Internet Group (http://opensource.go.com/)."
+ *    Alternately, this acknowledgment may appear in the software itself,
+ *    if and wherever such third-party acknowledgments normally appear.
+ *
+ * 4. The names "Tea", "TeaServlet", "Kettle", "Trove" and "BeanDoc" must
+ *    not be used to endorse or promote products derived from this
+ *    software without prior written permission. For written
+ *    permission, please contact opensource@dig.com.
+ *
+ * 5. Products derived from this software may not be called "Tea",
+ *    "TeaServlet", "Kettle" or "Trove", nor may "Tea", "TeaServlet",
+ *    "Kettle", "Trove" or "BeanDoc" appear in their name, without prior
+ *    written permission of the Walt Disney Internet Group.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE WALT DISNEY INTERNET GROUP OR ITS
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ * For more information about Tea, please see http://opensource.go.com/.
+ */
+
+package com.go.trove.classfile;
+
+import java.util.*;
+import java.io.*;
+
+/******************************************************************************
+ * This class corresponds to the LineNumberTable_attribute structure as
+ * defined  in section 4.7.6 of <i>The Java Virtual Machine Specification</i>.
+ * 
+ * @author Brian S O'Neill
+ * @version
+ * <!--$$Revision: 1.1 $-->, <!--$$JustDate:--> 00/11/27 <!-- $-->
+ */
+class LineNumberTableAttr extends Attribute {
+    private List mEntries = new ArrayList();
+    private boolean mClean = false;
+    
+    public LineNumberTableAttr(ConstantPool cp) {
+        super(cp, LINE_NUMBER_TABLE);
+    }
+    
+    public int getLineNumber(Location start) {
+        clean();
+        int index = Collections.binarySearch(mEntries, new Entry(start, 0));
+        if (index < 0) {
+            if ((index = -index - 2) < 0) {
+                return -1;
+            }
+        }
+        return ((Entry)mEntries.get(index)).mLineNumber;
+    }
+
+    public void addEntry(Location start, int line_number) {
+        check("line number", line_number);
+        mEntries.add(new Entry(start, line_number));
+        mClean = false;
+    }
+    
+    public int getLength() {
+        clean();
+        return 2 + 4 * mEntries.size();
+    }
+    
+    public void writeDataTo(DataOutput dout) throws IOException {
+        int size = mEntries.size();
+        dout.writeShort(size);
+        for (int i=0; i<size; i++) {
+            Entry entry = (Entry)mEntries.get(i);
+            
+            int start_pc = entry.mStart.getLocation();
+
+            check("line number table entry start PC", start_pc);
+
+            dout.writeShort(start_pc);
+            dout.writeShort(entry.mLineNumber);
+        }
+    }
+
+    private void check(String type, int addr) throws RuntimeException {
+        if (addr < 0 || addr > 65535) {
+            throw new RuntimeException("Value for " + type + " out of " +
+                                       "valid range: " + addr);
+
+        }
+    }
+
+    private void clean() {
+        if (!mClean) {
+            mClean = true;
+
+            // Clean things up by removing multiple mappings of the same
+            // start_pc to line numbers. Only keep the last one.
+            // This has to be performed now because the Labels should have
+            // a pc location, but before they did not. Since entries must be
+            // sorted ascending by start_pc, use a sorted set.
+
+            Set reduced = new TreeSet();
+            for (int i = mEntries.size(); --i >= 0; ) {
+                reduced.add(mEntries.get(i));
+            }
+
+            mEntries = new ArrayList(reduced);
+        }
+    }
+
+    static Attribute define(ConstantPool cp,
+                            String name,
+                            int length,
+                            DataInput din) throws IOException {
+
+        LineNumberTableAttr lineNumbers = new LineNumberTableAttr(cp);
+
+        int size = din.readUnsignedShort();
+        for (int i=0; i<size; i++) {
+            int start_pc = din.readUnsignedShort();
+            int line_number = din.readUnsignedShort();
+
+            lineNumbers.addEntry(new FixedLocation(start_pc), line_number);
+        }
+
+        return lineNumbers;
+    }
+
+    private static class Entry implements Comparable {
+        public final Location mStart;
+        public final int mLineNumber;
+        
+        public Entry(Location start, int line_number) {
+            mStart = start;
+            mLineNumber = line_number;
+        }
+
+        public int compareTo(Object other) {
+            int thisLoc = mStart.getLocation();
+            int thatLoc = ((Entry)other).mStart.getLocation();
+            
+            if (thisLoc < thatLoc) {
+                return -1;
+            }
+            else if (thisLoc > thatLoc) {
+                return 1;
+            }
+            else {
+                return 0;
+            }
+        }
+
+        public boolean equals(Object other) {
+            if (other instanceof Entry) {
+                return mStart.getLocation() == 
+                    ((Entry)other).mStart.getLocation();
+            }
+            return false;
+        }
+
+        public String toString() {
+            return "start_pc=" + mStart.getLocation() + " => " +
+                "line_number=" + mLineNumber;
+        }
+    }
+}