binthread.java

Huffman编码的java实现。含实验报告。

package gilyou;


import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.RandomAccessFile;

public class BinThread extends Thread {
	private File file = null;
	private HuffmanNode[] symbols;
	public BinThread(String fileName,HuffmanNode[] symbols){
		this.file = new File(fileName);
		this.symbols = symbols;
	}
	public void run(){
		Main.binCheckBox.setEnabled(false);
		RandomAccessFile binReader = null;
		BufferedWriter binWriter = null;
		byte firstSymbol;
		byte nextSymbol;
		int symbolLen = 0;
		int label = 1;
		label <<= 31;
		int buffer = 0;
		int size = 0;
		HuffmanNode pointer;
		try{
			binReader = new RandomAccessFile(file.getName(),"r");
			binWriter = new BufferedWriter(new FileWriter(new File(file.getName() + ".bin"),true));
			for (firstSymbol = binReader.readByte(); firstSymbol != -1;firstSymbol = nextSymbol ) {
				for (symbolLen = 1, nextSymbol = binReader.readByte(); nextSymbol == firstSymbol && nextSymbol != -1; symbolLen++)
					nextSymbol = binReader.readByte();
				for (pointer = symbols[(byte)firstSymbol+128]; pointer != null && symbolLen != pointer.symbolLen; pointer = pointer.right);
				size = pointer.codeWordLen;
				buffer = pointer.codeWord;
				int i;
				for( i = 0; i < 32 - size; i++);
				buffer <<= i;
				for(int j = 0; j < size; j++){
					if((buffer & label) == 0)
						binWriter.write("0");
					else 
						binWriter.write("1");
					buffer <<= 1;
				}
			}
		}catch(Exception e){
			e.printStackTrace();
		}finally{
			try{
				Main.binCheckBox.setEnabled(true);
				binReader.close();
				binWriter.close();
				this.interrupt();
			}catch(Exception e){	
			}
		}
	}
			
	}