Java ThreadPoolExecutor创建重复线程
我需要读取一个大的csv文件(328MB)并对其进行处理。每行的处理还包括调用Web服务 我第一次使用ThreadPoolExecutor。我的逻辑是,我将从csv中每100行吐出一个线程,该线程将运行和处理每一行,并将结果写入templ文件。完成所有线程后,我将读取临时文件并创建一个comined输出文件 我的分割文件并创建线程的方法Java ThreadPoolExecutor创建重复线程,java,multithreading,threadpool,Java,Multithreading,Threadpool,我需要读取一个大的csv文件(328MB)并对其进行处理。每行的处理还包括调用Web服务 我第一次使用ThreadPoolExecutor。我的逻辑是,我将从csv中每100行吐出一个线程,该线程将运行和处理每一行,并将结果写入templ文件。完成所有线程后,我将读取临时文件并创建一个comined输出文件 我的分割文件并创建线程的方法 private List<Thread> invokeWS(String csvFilename, String tempFolder) {
private List<Thread> invokeWS(String csvFilename, String tempFolder) {
List<Thread> processCsvThreadList = new ArrayList<Thread>();
//Thread Pool Executer
int corePoolSize = 3;
int maximumPoolSize = 6;
long keepAliveTime = 10;
ThreadFactory threadFactory = Executors.defaultThreadFactory();
ThreadPoolExecutor thrdPoolEx = new ThreadPoolExecutor(corePoolSize,
maximumPoolSize, keepAliveTime, TimeUnit.SECONDS,
new ArrayBlockingQueue<Runnable>(2));
try {
BufferedReader bfr = new BufferedReader(new FileReader(csvFilename));
String line = "";
int i = 0;
line = bfr.readLine();
Thread csvThread;
List<String> rowList = new ArrayList<String>();
do {
line = bfr.readLine();
if (line != null) {
rowList.add(line);
i++;
if (i % 100 == 0) {
csvThread = new Thread(new ProcessCsvRow(rowList,
tempFolder));
csvThread.start();
thrdPoolEx.execute(csvThread);
rowList = new ArrayList<String>();
processCsvThreadList.add(csvThread);
}
} else {
if (null != rowList && !rowList.isEmpty()) {
csvThread = new Thread(new ProcessCsvRow(rowList,
tempFolder));
csvThread.start();
thrdPoolEx.execute(csvThread);
processCsvThreadList.add(csvThread);
}
break;
}
} while (true);
} catch (FileNotFoundException fnf) {
fnf.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
finally{
thrdPoolEx.shutdown();
}
return processCsvThreadList;
}
private List invokeWS(字符串csvFilename,字符串tempFolder){
List processCsvThreadList=新建ArrayList();
//线程池执行器
int corePoolSize=3;
int maximumPoolSize=6;
长keepAliveTime=10;
ThreadFactory ThreadFactory=Executors.defaultThreadFactory();
ThreadPoolExecutor thrdPoolEx=新的ThreadPoolExecutor(corePoolSize,
maximumPoolSize、keepAliveTime、TimeUnit.s、,
新的ArrayBlockingQueue(2));
试一试{
BufferedReader bfr=新的BufferedReader(新文件读取器(csvFilename));
字符串行=”;
int i=0;
line=bfr.readLine();
线程csvThread;
List rowList=new ArrayList();
做{
line=bfr.readLine();
如果(行!=null){
行列表。添加(行);
i++;
如果(i%100==0){
csvThread=新线程(新进程)CSVROW(行列表,
临时文件夹);
csvThread.start();
execute(csvThread);
行列表=新的ArrayList();
processCsvThreadList.add(csvThread);
}
}否则{
if(null!=rowList&!rowList.isEmpty()){
csvThread=新线程(新进程)CSVROW(行列表,
临时文件夹);
csvThread.start();
execute(csvThread);
processCsvThreadList.add(csvThread);
}
打破
}
}虽然(正确);
}捕获(FileNotFoundException fnf){
fnf.printStackTrace();
}捕获(IOE异常){
e、 printStackTrace();
}
最后{
thrdPoolEx.shutdown();
}
返回进程csvthreadlist;
}
我的课程
public class ProcessCsvRow implements Runnable {
private List<String> csvRowsList;
private String tempDir;
public ProcessCsvRow(List<String> csvRowsList, String tempDir) {
this.csvRowsList = csvRowsList;
this.tempDir = tempDir;
}
@Override
public void run() {
UUID idOne = UUID.randomUUID();
FileWriter fw = null;
BufferedWriter bufferedWriter = null;
try {
String res = "";
fw = new FileWriter(new File(tempDir + "\\" + idOne.toString()+FilePropConstants.FILE_NAME_EXT_TMP));
bufferedWriter = new BufferedWriter(fw);
SentimentAnalyzer sentimentAnalyzer = new SentimentAnalyzer();
for (String csvRow : csvRowsList) {
//calling webservice for each row
res = sentimentAnalyzer.invokeSentWS(csvRow);
bufferedWriter.write(res);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (bufferedWriter != null) {
bufferedWriter.flush();
bufferedWriter.close();
}
if (fw != null) {
fw.close();
}
} catch (IOException ex) {
ex.printStackTrace();
}
}
}
公共类ProcessCsvRow实现可运行{
私人名单;
私有字符串tempDir;
公共进程csvrow(列表csvRowsList,字符串tempDir){
this.csvRowsList=csvRowsList;
this.tempDir=tempDir;
}
@凌驾
公开募捐{
UUID idOne=UUID.randomuid();
FileWriter fw=null;
BufferedWriter BufferedWriter=null;
试一试{
字符串res=“”;
fw=newfilewriter(新文件(tempDir+“\\”+idOne.toString()+FilePropConstants.File\u NAME\u EXT\u TMP));
bufferedWriter=新的bufferedWriter(fw);
感伤分析器感伤分析器=新建感伤分析器();
用于(字符串csvRow:csvRowsList){
//为每行调用webservice
res=感伤分析器.invokeSentWS(csvRow);
bufferedWriter.write(res);
}
}捕获(IOE异常){
e、 printStackTrace();
}最后{
试一试{
if(bufferedWriter!=null){
bufferedWriter.flush();
bufferedWriter.close();
}
如果(fw!=null){
fw.close();
}
}捕获(IOEX异常){
例如printStackTrace();
}
}
}
}
问题是,对于5行csv,是否应该创建一个临时文件,但当我运行此程序时,生成了两个临时文件,这是错误的。我坚信这不是一个逻辑问题,而是我实现ThreadPoolExecuter的方式
非常感谢您的帮助。您不应该创建线程,也不需要直接创建线程池 试一试
顺便说一句,每个线程都必须创建自己的输出文件,或者您需要锁定一个共享文件,或者您可以提交一个可调用文件,并让它返回您想要记录到提交线程的内容。这是因为您都在自己启动线程,并要求执行者执行它 更改:
csvThread = new Thread(new ProcessCsvRow(rowList, tempFolder));
csvThread.start();
thrdPoolEx.execute(csvThread);
rowList = new ArrayList<String>();
processCsvThreadList.add(csvThread);
csvThread=新线程(新进程csvrow(行列表,tempFolder));
csvThread.start();
execute(csvThread);
行列表=新的ArrayList();
processCsvThreadList.add(csvThread);
致:
csvThread=新线程(新进程csvrow(行列表,tempFolder));
execute(csvThread);
行列表=新的ArrayList();
processCsvThreadList.add(csvThread);
@PeterLawrey-我知道,但他想知道自己做错了什么,所以我解释了。一般来说,我认为他应该对生产者/消费者模型使用完全不同的方法,然后对每个线程批处理100个调用。谢谢Peter,它成功了。我修改了我的代码,最后添加了{taskExecutor.shutdown();尝试{taskExecutor.waitTermination(Long.MAX_VALUE,TimeUnit.NANOSECONDS)}catch(InterruptedException e){}除非您真的需要等待线程池完成,否则我只调用shutdown();
csvThread = new Thread(new ProcessCsvRow(rowList, tempFolder));
csvThread.start();
thrdPoolEx.execute(csvThread);
rowList = new ArrayList<String>();
processCsvThreadList.add(csvThread);
csvThread = new Thread(new ProcessCsvRow(rowList, tempFolder));
thrdPoolEx.execute(csvThread);
rowList = new ArrayList<String>();
processCsvThreadList.add(csvThread);