一道线程交替读取的面试题
有两个单词的txt文本a.txt和b.txt，a是以换行区分单词，b是 换行或者空格符。写一个程序，交替读取a和b文件中的单词保存在文件c中。
代码如下：

package com.kaiying.face;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.io.InputStream;import java.io.OutputStream;import java.util.concurrent.locks.Condition;import java.util.concurrent.locks.Lock;import java.util.concurrent.locks.ReentrantLock;public class FileWriteAndReadTest {private Lock lock = new ReentrantLock();private Condition condition = lock.newCondition();private Condition otherCondition = lock.newCondition();private OutputStream out;private boolean turnA = true;//读A  false 读B文件private boolean empty = false;//判断有一个文件的单词全部读完public FileWriteAndReadTest() {try {out = new FileOutputStream("d.txt");} catch (FileNotFoundException e) {e.printStackTrace();}}class ReadFileA implements Runnable {public void run() {try {lock.lock();InputStream in = new FileInputStream("a.txt");int r = 0;while ((r = in.read()) != -1) {while (!turnA) {otherCondition.await();}writeByte(r);if (r == 10) {// 换行if (!empty) {turnA = false;System.out.println("A");condition.signal();}}}turnA = false;empty = true;} catch (Exception e) {e.printStackTrace();} finally {lock.unlock();}}}class ReadFileB implements Runnable {public void run() {try {lock.lock();InputStream in = new FileInputStream("b.txt");int r = 0;while ((r = in.read()) != -1) {while (turnA) {condition.await();}writeByte(r);if (r == 10 || r == 32) {// 换行  空格if (!empty) {System.out.println("B");turnA = true;otherCondition.signal();}}}turnA = true;empty = true;} catch (Exception e) {e.printStackTrace();} finally {lock.unlock();}}}public void writeByte(int byteWord) {try {out.write(byteWord);} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}public static void main(String[] args) {FileWriteAndReadTest test = new FileWriteAndReadTest();ReadFileA fileA = test.new ReadFileA();ReadFileB fileB = test.new ReadFileB();new Thread(fileA).start();new Thread(fileB).start();}}