File	Doc	Category	Size	Date	Package
LineNumberTableAttribute.java	API Doc	J2ME CLDC 1.1	9004	Wed Feb 05 15:56:04 GMT 2003	kdp.classparser.attributes

LineNumberTableAttribute

• java.lang.Object
  • Attribute

Fields Summary
private int	attributeNameIndex index into the constant pool table containing the name of this class
private int	attributeLength length of this attribute in bytes
private int	lineNumberTableLength number of elements in the line number table array
private LineNumberTable[]	lineNumberTable each entry indicates that the line number in the original source file changes at a given point in the code array.

Constructors Summary

public LineNumberTableAttribute(DataInputStream iStream, int attributeNameIndex, int attributeLength) Constructor. Reads the LineNumberTableAttribute attribute from the class file. param iStream the input stream on which to read the class file param attributeNameIndex attributeNameIndex member of attribute structure. param attributeLength attributeLength member of attribute structure. exception IOException pass IOExceptions up this.attributeNameIndex = attributeNameIndex; this.attributeLength = attributeLength; //read in the length of the LineNumberTable array lineNumberTableLength = iStream.readUnsignedShort (); //allocate space for the LineNumberTable array and read in the data lineNumberTable = new LineNumberTable[lineNumberTableLength]; for (int lcv = 0; lcv < lineNumberTableLength; ++lcv) { lineNumberTable[lcv] = new LineNumberTable (); lineNumberTable[lcv].startPC = iStream.readUnsignedShort (); lineNumberTable[lcv].lineNumber = iStream.readUnsignedShort (); }

Methods Summary
public boolean	containsLine(int lineNumber) Determine if this lineNumber table contains the specified source file line number. param lineNumber source file line number return boolean true if line number was found, false otherwise boolean found = false; int index = 0; //loop through each entry in the line number table until //the specified line number is found or there are no //entries left while ((!found) && (index < lineNumberTableLength)) { if (lineNumber == lineNumberTable[index].lineNumber) found = true; else ++index; } return found;
public int	getCodeIndexBySourceLineNumber(int lineNumber) Returns the first code index associated with the specified source file line number. param lineNumber source file line number return int index into code array of first bytecode of this instruction If the line number does not map to a code array index then return -1 boolean found = false; int index = 0; //loop through line number table until we find an entry with the //specified source file line number or run out of entries while ((!found) && (index < lineNumberTableLength)) { if (lineNumber == lineNumberTable[index].lineNumber) found = true; else ++index; } //if an entry was found return the code array index associated with it if (found) return (lineNumberTable[index].startPC); else return -1; //no entry found so return -1
public int	getCurrentLineCodeIndex(long offset) int currentIndex = getIndexThatContainsOpcode(offset); Log.LOGN(3, "getCurrent: index=" + currentIndex); return currentIndex;
public int	getDupCurrentExecutableLineCodeIndex(long offset) int firstIndex = getNextExecutableLineCodeIndex(offset, false); if (firstIndex == -1) return -1; firstIndex--; return getOtherLineIndex(firstIndex);
private int	getIndexThatContainsOpcode(long offset) Returns the line that this opcode offset lies on for (int i=0; i < lineNumberTableLength - 1; i++) { if (offset >= lineNumberTable[ i ].startPC && offset < lineNumberTable[ i + 1 ].startPC) { return i; } } if (offset >= lineNumberTable[ lineNumberTableLength - 1 ].startPC) return lineNumberTableLength - 1; return -1; // lineNumberTable[ 0 ].lineNumber;
public int	getLineNumberFromIndex(int index) if (index == -1 || index == lineNumberTableLength - 1) return (-1); return lineNumberTable[index].lineNumber;
public int[][]	getLineNumbersAndIndicesAsArray() int lineArray[][] = new int[lineNumberTableLength][2]; for (int lcv = 0; lcv < lineNumberTableLength; ++lcv) { lineArray[lcv][0] = lineNumberTable[lcv].lineNumber; lineArray[lcv][1] = lineNumberTable[lcv].startPC; } return lineArray;
public int	getNextExecutableLineCodeIndex(long offset) return getNextExecutableLineCodeIndex(offset, true);
private int	getNextExecutableLineCodeIndex(long offset, boolean logging) int firstIndex = getIndexThatContainsOpcode(offset); if (logging) Log.LOGN(3, "getNext: firstIndex=" + firstIndex); int otherIndex; if ((otherIndex = getOtherLineIndex(firstIndex)) != -1) { if (logging) Log.LOGN(3, "getNext: otherIndex=" + otherIndex); if (otherIndex < firstIndex) { if (logging) Log.LOGN(3, "getNext: otherIndex < firstIndex"); return otherIndex + 1; } else { if (logging) Log.LOGN(3, "getNext: otherIndex > firstIndex"); return firstIndex + 1; } } if (firstIndex+1 < lineNumberTableLength) return firstIndex + 1; else return -1;
public long	getOffsetofDupNextLine(int index) if (index == -1 || index == lineNumberTableLength - 1) return -1; return lineNumberTable[index + 1].startPC;
private int	getOtherLineIndex(int index) for (int i=0; i < lineNumberTableLength; i++) { if (i == index) continue; if (lineNumberTable[ i ].lineNumber == lineNumberTable[ index ].lineNumber) { return i; } } return -1;
public long	getStartPCFromIndex(int index) if (index == -1) return -1; return lineNumberTable[index].startPC;
public java.lang.String	toString(ConstantPoolInfo[] constantPool) Returns the LineNumberTableAttribute attribute in a nice easy to read format as a string. param constantPool constant pool of the class file return String the attribute as a nice easy to read String ConstantUtf8Info utf8Info; String s = new String (""); utf8Info = (ConstantUtf8Info) constantPool[attributeNameIndex]; s = s + "\t" + utf8Info.toString (); /* for (int lcv = 0; lcv < lineNumberTableLength; ++lcv) { s = s + "\n\t\t\t\tStart PC= " + lineNumberTable[lcv].startPC; s = s + "\tLine Number= " + lineNumberTable[lcv].lineNumber; } */ return s;