pooledweblog.java

char44-2 处理web服务器的记录文件 提供了本书第4章的处理web服务器的记录文件实例的源程序；

//PooledWeblog.java
import java.io.*;
import java.util.*;
import com.macfaq.io.SafeBufferedReader;
public class PooledWeblog {
	private BufferedReader in;
	private BufferedWriter out;
	private int numberOfThreads;
	private List entries = Collections.synchronizedList(new
		LinkedList( ));
	private boolean finished = false;
	private int test = 0;
	public PooledWeblog(InputStream in, OutputStream out,
		int numberOfThreads) {
		this.in = new BufferedReader(new InputStreamReader(in));
		this.out = new BufferedWriter(new OutputStreamWriter(out));
		this.numberOfThreads = numberOfThreads;
	}
	public boolean isFinished( ) {
		//当结束时返回
		return this.finished;
	}
	public int getNumberOfThreads( ) {
		return numberOfThreads;
	}
	public void processLogFile( ) {
		for (int i = 0; i < numberOfThreads; i++) {
			//去创建新的线程
			Thread t = new LookupThread(entries, this);
			t.start( );
		}
		try {
			String entry = null;
			while ((entry = in.readLine( )) != null) {
				if (entries.size( ) > numberOfThreads) {
					try {
						Thread.sleep((long) (1000.0/numberOfThreads));
					}
					catch (InterruptedException e) {}
					continue;
				}
				synchronized (entries) {
					entries.add(0, entry);
					entries.notifyAll( );
				}
				Thread.yield( );
			} // 循环终止
		}
		catch (IOException e) {
			System.out.println("Exception: " + e);
		}
		this.finished = true;
		// 结束那些仍然等待的线程
		synchronized (entries) {
			entries.notifyAll( );
		}
	}
	public void log(String entry) throws IOException {
		out.write(entry + System.getProperty("line.separator", "\r\n"));
		out.flush( );
	}
	public static void main(String[] args) {
		try {
			PooledWeblog tw = new PooledWeblog(new FileInputStream(args[0]),
				System.out, 100);
			tw.processLogFile( );
		}
		catch (FileNotFoundException e) {
			System.err.println("Usage: java PooledWeblog logfile_name");
		}
		catch (ArrayIndexOutOfBoundsException e) {
			System.err.println("Usage: java PooledWeblog logfile_name");
		}
		catch (Exception e) {
			System.err.println(e);
			e.printStackTrace( );
		}
	} 
}