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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package org.apache.bcel.classfile;
import java.io.DataInput;
import java.io.DataOutputStream;
import java.io.IOException;
/**
* This class represents a (PC offset, line number) pair, i.e., a line number in
* the source that corresponds to a relative address in the byte code. This
* is used for debugging purposes.
*
* @version $Id$
* @see LineNumberTable
*/
public final class LineNumber implements Cloneable, Node {
/** Program Counter (PC) corresponds to line */
private short start_pc;
/** number in source file */
private short line_number;
/**
* Initialize from another object.
*
* @param c the object to copy
*/
public LineNumber(final LineNumber c) {
this(c.getStartPC(), c.getLineNumber());
}
/**
* Construct object from file stream.
*
* @param file Input stream
* @throws IOEXception if an I/O Exception occurs in readUnsignedShort
*/
LineNumber(final DataInput file) throws IOException {
this(file.readUnsignedShort(), file.readUnsignedShort());
}
/**
* @param start_pc Program Counter (PC) corresponds to
* @param line_number line number in source file
*/
public LineNumber(final int start_pc, final int line_number) {
this.start_pc = (short) start_pc;
this.line_number = (short)line_number;
}
/**
* Called by objects that are traversing the nodes of the tree implicitely
* defined by the contents of a Java class. I.e., the hierarchy of methods,
* fields, attributes, etc. spawns a tree of objects.
*
* @param v Visitor object
*/
@Override
public void accept( final Visitor v ) {
v.visitLineNumber(this);
}
/**
* Dump line number/pc pair to file stream in binary format.
*
* @param file Output file stream
* @throws IOEXception if an I/O Exception occurs in writeShort
*/
public final void dump( final DataOutputStream file ) throws IOException {
file.writeShort(start_pc);
file.writeShort(line_number);
}
/**
* @return Corresponding source line
*/
public final int getLineNumber() {
return 0xffff & line_number;
}
/**
* @return PC in code
*/
public final int getStartPC() {
return 0xffff & start_pc;
}
/**
* @param line_number the source line number
*/
public final void setLineNumber( final int line_number ) {
this.line_number = (short) line_number;
}
/**
* @param start_pc the pc for this line number
*/
public final void setStartPC( final int start_pc ) {
this.start_pc = (short) start_pc;
}
/**
* @return String representation
*/
@Override
public final String toString() {
return "LineNumber(" + start_pc + ", " + line_number + ")";
}
/**
* @return deep copy of this object
*/
public LineNumber copy() {
try {
return (LineNumber) clone();
} catch (final CloneNotSupportedException e) {
// TODO should this throw?
}
return null;
}
}
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