那些遇到过的问题

小编use*_*483的帖子

Netty 4多个客户端

我需要让客户端能够建立许多连接.我使用Netty 4.0.不幸的是,所有现有示例都没有显示如何创建大量连接.

public class TelnetClient {
    private Bootstrap b;
    public TelnetClient() {
        b = new Bootstrap();
    }
    public void connect(String host, int port) throws Exception {
        try {
            b.group(new NioEventLoopGroup()).channel(NioSocketChannel.class).remoteAddress(host, port).handler(new TelnetClientInitializer());
            Channel ch = b.connect().sync().channel();
            ChannelFuture lastWriteFuture = null;
            BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
            for (;;) {
                String line = in.readLine();
                if (line == null) break;
                lastWriteFuture = ch.write(line + "\r\n");
                if (line.toLowerCase().equals("bye")) {
                    ch.closeFuture().sync();
                    break;
                }
            }
            if (lastWriteFuture != null) lastWriteFuture.sync();
        } finally {
            b.shutdown();
        } …
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java connection client netty

use*_*483
lucky-day
11
推荐指数
1
解决办法
8840
查看次数

Java获取边框颜色和大小 

JTextField tf = new JTextField();
tf.setBorder(new LineBorder(Color.red, 2));
Border border = tf.getBorder();
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如何获得边框颜色和大小？

size swing border colors

use*_*483
2016 08-26
8
推荐指数
2
解决办法
6002
查看次数

JEdi​​torPane 中的 JButton

http://weblogs.java.net/blog/aim/archive/2007/07/embedding_swing.html
http://docs.oracle.com/javase/1.5.0/docs/api/index.html?javax/swing /text/html/ObjectView.html

我将 html 代码添加到 JEditorPane：

    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
    <html>
      <body>
          <table width="90%" height="90%" align="center">
              <tr align="center">
                  <td align="center">
                      <object classid="javax.swing.JButton" label="just do it">
                      </object>
                  </td>
              </tr>
          </table>
      </body>
    </html>
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图像

我怎样才能控制这个按钮呢？（更改大小、颜色、添加监听器等）

我解决了这个问题，一个工作示例：

    import java.awt.*;
    import javax.swing.*;
    import javax.swing.text.html.HTMLEditorKit;
    import javax.swing.text.ViewFactory;
    import javax.swing.text.AttributeSet;
    import javax.swing.text.Element;
    import javax.swing.text.html.ObjectView;
    import javax.swing.text.AbstractDocument;
    import javax.swing.text.View;
    import javax.swing.text.StyleConstants;

    import javax.swing.text.*;
    import javax.swing.text.html.HTML;
    import javax.swing.text.html.HTMLEditorKit;
    import java.net.URL;

    public class EditorPaneTest extends JFrame
    {
public EditorPaneTest()
{
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setLocationByPlatform(true);        

    JEditorPane editPane = new …
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java swing object jeditorpane jbutton

use*_*483
2020 06-20
3
推荐指数
1
解决办法
2585
查看次数

JPopupMenu删除背景和边框

JPopupMenu http://s010.radikal.ru/i313/1209/25/2213e2145879.gif

我需要删除的背景和Border在JPopupMenu.JPopupMenu应该是完全透明的.覆盖paintComponent不会给出积极的结果.我也尝试在BasicMenuItemUI/ PopupMenuUI和MenuItemUI/中找到解决方案,BasicPopupMenuUI但发现渲染背景和边框不在其中.

public class CustomMenuItemUI extends BasicMenuItemUI {
    protected MouseInputListener mouseInputListener;
    protected MenuDragMouseListener menuDragMouseListener;
    public static ComponentUI createUI(JComponent c) {
        return new CustomMenuItemUI();
    }

    private static float alpha = 0.0f;
    private static float selectionAlpha = 0.0f;

    public static float getAlpha() {
        return alpha;
    }

    public static void setAlpha(float _alpha) {
        alpha = _alpha;
    }

    @Override
    public void installUI(JComponent c) {
        super.installUI(c);
        menuItem.setOpaque(false);
    } …
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java swing background border jpopupmenu

use*_*483
2019 08-25
2
推荐指数
1
解决办法
2013
查看次数

访问Java的私有字段

javax.swing.text.html.ImageView中; 第111和258-267行
http://javasourcecode.org/html/open-source/jdk/jdk-6u23/javax/swing/text/html/ImageView.java.html

public class ImageView extends View {
    ....
    private float vAlign;
    ....
}
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我的节目:

.....
ImageView layeredPane = (ImageView) view;
Field privateStringField = layeredPane.getClass().getDeclaredField("vAlign");
privateStringField.setAccessible(true);
layeredPane.vAlign = 2.0;
.....
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我明白了:

Test.java:80:错误:vAlign在ImageView中具有私有访问权限layeredPane.vAlign = 2.0;

我如何解决它？我需要设置一个2.0的值

java private-members imageview

use*_*483
2012 05-03
0
推荐指数
1
解决办法
276
查看次数

NullPointerException没有真正的原因 

    Character c = null;
    if (c != 'P') c = 'G';
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这是一个简单的代码,它会让我对结果感到伤心.而不是条件,我得到一个错误NullPointerException.虽然无效!='P'并且必须满足条件.我很难解决额外的验证问题c!在条件"if"中为null.它应该是吗？有没有办法进行比较而不是错误？事实证明,所有代码都充满了这些不必要的检查.

java nullpointerexception

use*_*483
lucky-day
0
推荐指数
2
解决办法
123
查看次数

标签 统计

java ×5

swing ×3

border ×2

background ×1

client ×1

colors ×1

connection ×1

imageview ×1

jbutton ×1

jeditorpane ×1

jpopupmenu ×1

netty ×1

nullpointerexception ×1

object ×1

private-members ×1

size ×1