Java 这是fork-in-join的正确代码吗?
我开始在Java 这是fork-in-join的正确代码吗?,java,parallel-processing,fork-join,Java,Parallel Processing,Fork Join,我开始在Java中阅读for in-join,所以我的目标是验证JavaMail中具有附件的消息 我怀疑这是否正确。因为我看到一些教程将数组拆分为两部分,每个lopp。我把我所有的类代码放在下面来演示我做了什么 package service.forkinjoin; import java.io.IOException; import java.util.ArrayList; import java.util.Iterator; import java.util.List; import ja
Java
中阅读for in-join
,所以我的目标是验证JavaMail
中具有附件的消息
我怀疑这是否正确。因为我看到一些教程将数组拆分为两部分,每个lopp
。我把我所有的类代码放在下面来演示我做了什么
package service.forkinjoin;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.RecursiveTask;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Multipart;
import javax.mail.Part;
import javax.mail.internet.MimeBodyPart;
import service.FileUtil;
public class SepareteMessagesProcess extends RecursiveTask<List<Message>> {
private static final long serialVersionUID = 7126215365819834781L;
private List<Message> listMessages;
private static List<Message> listMessagesToDelete = new ArrayList<>();
private final int threadCount = Runtime.getRuntime().availableProcessors();
public SepareteMessagesProcess(List<Message> listMessages) {
this.listMessages = listMessages;
}
@Override
protected List<Message> compute() {
if (this.listMessages.size() <= threadCount) {
try {
this.separateMessages(this.listMessages);
} catch (MessagingException | IOException e) {
e.printStackTrace();
}
} else {
int[] arrayMaxIndex = this.generateIndexs(this.listMessages);
List<SepareteMessagesProcess> list = this.splitList(this.listMessages, arrayMaxIndex);
invokeAll(list);
}
return listMessagesToDelete;
}
private void separateMessages(List<Message> listMessages) throws MessagingException, IOException {
for (Iterator<Message> iterator = listMessages.iterator(); iterator.hasNext();) {
Message message = (Message) iterator.next();
if ((this.hasNoAttachment(message.getContentType()) || (this.hasNoXmlAttachment(message)))) {
listMessagesToDelete.add(message);
}
}
}
private List<SepareteMessagesProcess> splitList(List<Message> listMessages, int[] arrayMaxIndex) {
List<SepareteMessagesProcess> list = new ArrayList<>(this.threadCount);
int end = 0;
int start = 0;
for (int i = 0; i < this.threadCount; i++) {
end += (arrayMaxIndex[i]);
list.add(new SepareteMessagesProcess(listMessages.subList(start, end)));
start += arrayMaxIndex[i];
}
return list;
}
private int[] generateIndexs(List<Message> listMessages) {
int value = listMessages.size() / this.threadCount;
int[] arrayMaxIndex = new int[this.threadCount];
for (int i = 0; i < this.threadCount; i++) {
arrayMaxIndex[i] = value;
}
arrayMaxIndex[this.threadCount - 1] += listMessages.size() % threadCount;
return arrayMaxIndex;
}
private boolean hasNoAttachment(String content) {
return !content.contains("multipart/MIXED");
}
private boolean hasNoXmlAttachment(Message message) throws IOException, MessagingException {
Multipart multipart = (Multipart) message.getContent();
for (int i = 0; i < multipart.getCount(); i++) {
MimeBodyPart mimeBodyPart = (MimeBodyPart) multipart.getBodyPart(i);
if (Part.ATTACHMENT.equalsIgnoreCase(mimeBodyPart.getDisposition())) {
if (FileUtil.isXmlFile(mimeBodyPart.getFileName())) {
return false;
}
}
}
return true;
}
}
package service.forkinjoin;
导入java.io.IOException;
导入java.util.ArrayList;
导入java.util.Iterator;
导入java.util.List;
导入java.util.concurrent.RecursiveTask;
导入javax.mail.Message;
导入javax.mail.MessaginException;
导入javax.mail.Multipart;
导入javax.mail.Part;
导入javax.mail.internet.MimeBodyPart;
导入服务.FileUtil;
公共类SeparateMessageProcess扩展了RecursiveTask{
私有静态最终长serialVersionUID=7126215365819834781L;
私人列表信息;
private static List listMessagesToDelete=new ArrayList();
private final int threadCount=Runtime.getRuntime().availableProcessors();
公共分离消息流程(列表消息){
this.listMessages=listMessages;
}
@凌驾
受保护列表计算(){
如果(this.listMessages.size()No.)不需要在此处重写教程,只需按照它给出的示例进行操作,例如:
if (problem is small)
directly solve problem
else {
split problem into independent parts
fork new subtasks to solve each part
join all subtasks
compose result from subresults
}
我有一个疑问,如果我有一个包含电子邮件的列表,那么我想按每个发件人来分隔in文件夹,是否可以使用fork-in-join?使用hashmap来分隔?