semaphore.java

高质量Java程序设计 源代码

package net.betterjava.sample.xml.bind.test;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;

class Semaphore {
	private int READY_NUM = 5;
	private int threadCounter = 0;

	private long elapseTime = 0;

	private int round;

	private String testFileName = "data.";
	private int testFileCount = 10;

	private String[] rawData = new String[10];
	private int[] inputData;
	private int nextInputData;

	public synchronized void elapse(long time) {
		elapseTime += time;
	}

	public Semaphore(int aReadyNum, int aRound) throws IOException {
		READY_NUM = aReadyNum;
		round = aRound;
		generateInputData();

	}

	private String readTestString(String fileName) throws IOException {
		FileReader reader = new FileReader(fileName);
		BufferedReader bfReader = new BufferedReader(reader);
		StringBuffer sampleSB = new StringBuffer();
		String lineStr = bfReader.readLine();
		while (lineStr != null) {
			sampleSB.append(lineStr + "\n");
			lineStr = bfReader.readLine();
		}
		return sampleSB.toString();
	}

	private void generateInputData() throws IOException {
		for (int i = 0; i < testFileCount; i++) {
			rawData[i] = readTestString(testFileName + i);
		}

		inputData = new int[round];
		for (int i = 0; i < round; i++) {
			double d = Math.random();
			int index = ((int) (d * 10)) % testFileCount;
			//System.out.println(index);
			inputData[i] = index;
		}
	}

	public synchronized String nextInput() {
		return rawData[inputData[nextInputData++]];
	}

	public boolean hasNext() {
		return nextInputData != inputData.length;
	}

	public void waitAllReady() {
		if (threadCounter == READY_NUM) {
			return;
		}

		synchronized (this) {
			threadCounter++;
			if (threadCounter < READY_NUM) {
				try {
					wait();
				} catch (InterruptedException exp) {
					System.out.println("interrupted exception in Semaphore");
				}
			} else
				notifyAll();
			System.out.println(
				Thread.currentThread() + " start at " + System.currentTimeMillis());
		}
	}

	public long getElapseTime() {
		return elapseTime;
	}
}