小编You*_*ans的帖子

开发模式出错

[ERROR] [cbd] - Line 15: The import com.google.appengine.api.datastore cannot be resolved

User.java

@Entity
public class User implements Serializable {

    private static final long serialVersionUID = 1L;

    @Id
    @Column(name="id")
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Key id;

    private String googleID;

    private String firstName;

    private String lastName;

    private String password;

    private String gender;

    private String email;


    @OneToOne(cascade=CascadeType.ALL)
    @JoinColumn(name="key")
    private AuthenticationToken token= AuthenticationToken();
    ......}

AuthenticationToken.java

public class AuthenticationToken implements Serializable {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    @Id
    @Column(name="key")
    @GeneratedValue(strategy …

我有这种情况

. . . 公共无效onClick（小部件发送者）{

. . . . PreferencesWidget.this.callback.onSuccess(feed.getText());

. . . . 隐藏（）;

}

如何仅删除此点

注意*点之间有空格

我知道第一个是类,第二个是接口但重点是,为什么客户端服务扩展了RemoteService,而ServiceImpl类扩展了RemoteServiceServlet

那么幕后真的是什么？!

考虑如下 Java 对象：

class User {

  String name;

  int age;

  String locationJson; // this is a json already

  //allArgsConstructor, getters & setters
}

所以当我们这样做时

import com.fasterxml.jackson.databind.ObjectMapper;
....

User user = new User("Max", 13, "{\"latitude\":30.0000,\"longitude\":32.0000}");

new ObjectMapper().writeValueAsString(user)), String.class);

我期待类似的事情：

{
  "name": "Max",
  "age": "13",
  "locationJson": {"latitude":30.0000, "longitude":32.0000}
}

相反，我将它作为一个 json 值包裹在双引号中，并用反斜杠跳过，因为它是双 json 化的- 如果这实际上是一个动词 -

{
  "name": "Max",
  "age": "13",
  "locationJson": "{\"latitude\":30.0000, \"longitude\":32.0000}"
}

package donut;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.geom.AffineTransform;
import java.awt.geom.Ellipse2D;

import javax.swing.JPanel;


public class Board extends JPanel{

    public void paint(Graphics g)
    {
      super.paint(g);

      Graphics2D g2 = (Graphics2D) g;

      RenderingHints rh =
            new RenderingHints(RenderingHints.KEY_ANTIALIASING,
                               RenderingHints.VALUE_ANTIALIAS_ON);

      rh.put(RenderingHints.KEY_RENDERING,
             RenderingHints.VALUE_RENDER_QUALITY);

      g2.setRenderingHints(rh);

      Dimension size = getSize();
      double w = size.getWidth();
      double h = size.getHeight();

      Ellipse2D e = new Ellipse2D.Double(0, 0, 80, 130);
      g2.setStroke(new BasicStroke(1));
      g2.setColor(Color.gray);


      for (double deg = 0; deg < 360; deg += 5) { …

我使用GWT构建了一个简单的Web应用程序并将其部署到Google App Engine现在我想构建我的数据库并将其集成到我的网站我搜索了所有我发现的Google Cloud SQL 并且我必须付费

任何免费的解决方案.我只想为1个用户构建简单的项目

*提示:数据库使用MYSQL

我有这个计时器用于Star.png通过JFrame & JPanel

移动具有计时器的星的功能:

private final static int HEIGHT = 300;
.
.//more code here
.
.
  x=y=0;
.
. 

public void downRight() {
    Timer localTimer = new Timer(100, null);
      localTimer.setRepeats(false);
    localTimer.addActionListener(new ActionListener() {
        @Override
        public void actionPerformed(ActionEvent e) {    
                x++;
                y++;
                repaint();
        }
    });
    int xTest=0;
    while (y < HEIGHT) {
        System.out.println("x "+(++xTest)+" y "+y);
        localTimer.start();
   }
    System.out.println("Reached");
}

运行计时器并测试xTest时,y值发现以下内容:

x 1 y 0

x 2 y 0

x 3 y 0

..... More Outputs here …

我试图理解线程的行为,所以我做了代码的和平:

    public class Threads extends Thread {
        private Account account = new Account();
        public static void main(String[] args) {
            Threads t = new Threads();
            t.start();
            t.interrupt();
        }
   @Override
    synchronized public void run() {
        System.out.println("Running...");
        account.func();account.func2();
    }

}
class Account {

    public synchronized void func()  {
        try {
            System.out.println("func");
            wait(1000);
            System.out.println("hi func");
        } catch (InterruptedException ex) {
            System.out.println("Ex func");
        }
    }
    public synchronized void func2()  {
        try {
            System.out.println("func2");
           wait(2000);
            System.out.println(Thread.currentThread().isInterrupted());
            System.out.println("Hi func2");
        } catch (InterruptedException ex) {
            System.out.println("Ex func2");
        } …

我正在尝试制作一个程序来格式化硬盘,现在我被困在我搜索的格式代码中,我发现SHFormatDrive()但是我发现win xp后来支持的功能以及我找不到使用它有任何帮助!