java - 定期检查文件状态是否更改 RCP

Question

定期检查 XML 文件中的书籍状态的方法的概念是什么，如果状态发生变化，它将通过 RCP 发出警报？我想创建可以执行此操作的任务。我在 JFrame 中有主类。

这是 XmlFile 和 POJO。

 package net.kxyz;

 import java.io.File;
 import java.io.FileWriter;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.parsers.ParserConfigurationException;
 import javax.xml.transform.Transformer;
 import javax.xml.transform.TransformerConfigurationException;
 import javax.xml.transform.TransformerException;
 import javax.xml.transform.TransformerFactory;
 import javax.xml.transform.dom.DOMSource;
 import javax.xml.transform.stream.StreamResult;
 import org.w3c.dom.Document;
 import org.w3c.dom.Element;
 import org.w3c.dom.Node;
 import org.w3c.dom.NodeList;
 import org.xml.sax.SAXException;
 import xyz.libary.Book;
 import xyz.libary.DataInterface;

 /**
  *
  * @author kuman
  */
 public class XmlDataInterfaceImpl implements DataInterface {

File fXmlFile = new File("baza.xml");
ArrayList<Book> book = new ArrayList<>();

@Override
public void updateBook(Book book2) {

    int index = book2.getId();
    this.book.get(index).setTitle(book2.getTitle());
    this.book.get(index).setAuthor(book2.getAuthor());
    this.book.get(index).setYear(book2.getYear());
    this.book.get(index).setState(book2.isState());

}

@Override
public ArrayList<Book> getAllBooks() {
    //code
    return book;
}

public void addBook(Book book2) {
    //code
}

@Override
public void deleteBook(Book book) {
    //code
}

private void toFile() {

    //code

}

 }

POJO

 /*
  * To change this template, choose Tools | Templates
  * and open the template in the editor.
  */
 package xyz.libary;

 /**
  *
  * @author kuman
  */
 public class Book {
int id;
String title;
String author;
int year;
Boolean state;

public Book() {};
public Book(int id, String title, String author, int year) {
    this.id = id ;
    this.title = title;
    this.author = author;
    this.year = year;
    this.state = true;
}

public int getId() {
    return id;
}

public void setId(int id) {
    this.id = id;
}


public String getAuthor() {
    return author;
}

public void setAuthor(String author) {
    this.author = author;
}

public Boolean isState() {
    return state;
}

public void setState(Boolean state) {
    this.state = state;
}

public String getTitle() {
    return title;
}

public void setTitle(String title) {
    this.title = title;
}

public int getYear() {
    return year;
}

public void setYear(int year) {
    this.year = year;
}

public void setState(Object value) {
    this.state=(Boolean)(value);
}



}

Answer 1

您可以创建一个在 xyz 时间后重复的作业。

final Job job = new Job("Name")
{

  @Override
  protected IStatus run( final IProgressMonitor monitor )
  {
  // do something
    schedule( delay ) // schedule again after "delay" mili seconds
    return status;
  }
};
job.schedule();

参见https://www.eclipse.org/articles/Article-Concurrency/jobs-api.html或

和 http://help.eclipse.org/kepler/index.jsp?topic=%2Forg.eclipse.platform.doc.isv%2Freference%2Fapi%2Forg%2Feclipse%2Fcore%2Fruntime%2Fjobs%2FJob.html