小编Kau*_*ain的帖子

我想通过progamatically获得已经放置的面板的网格袋约束.我怎么做？？

我有一个JTable表格模型.但是在将列名传递给表模型时,它不会更新列名.有人可以告诉我为什么吗？

class MyTableModelTwo extends AbstractTableModel {

    private Object[][] data;
    private String[] columnNames = {"Name", "ID Number", "CGPA"};

    public MyTableModelTwo(Object[][] data) {
        this.data = data;

    }

    @Override
    public int getRowCount() {
        return data.length;
    }

    @Override
    public int getColumnCount() {
        return columnNames.length;
    }

    @Override
    public Object getValueAt(int rowIndex, int columnIndex) {
        return data[rowIndex][columnIndex];
    }

    @Override
    public Class getColumnClass(int c) {
        return getValueAt(0, c).getClass();
    }

    @Override
    public boolean isCellEditable(int rowIndes, int columnIndex) {
        return false;
        }

    @Override
    public void setValueAt(Object value, …

我有一个JPanel设置为BorderLayout.我JPanels在这个面板中添加了2个,一个是南,一个是中心.在中心面板,我添加了一个LowerBevelBorder.我发现我无法在主框架和边框之间留下间隙.我怎么做？这是我的panel1.setBorder(BorderFactory.createLoweredBevelBorder());

我有2个面板.第一个面板有一个组合框.根据所选组合框中项目的值,它下面的面板必须更改.在组合框的动作侦听器中,当我尝试更改面板时,它不会更改.为什么是这样？

cb1.addActionListener(new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            String s = (String) cb1.getSelectedItem();
            if (s.equals("Invoice")) {
                panel3Customizera();
                g.gridy = 2;
                remove(panel3);
                add(panel3, g);
            } else {
                panel3Customizerb();
                g.gridy = 2;
                add(panel3, g);
            }

        }
    });

panel3customizer将元素添加到panel3.panel 3中添加到jframe中.可在此处找到指向整个代码的链接

我正在尝试制作一个基本的spring mvc 3.0应用程序.但是当我启动我的服务器时,我收到以下错误

java.lang.NoSuchMethodError: org.springframework.beans.factory.annotation.InjectionMetadata.<init>(Ljava/lang/Class;)V
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findPersistenceMetadata(PersistenceAnnotationBeanPostProcessor.java:350)
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessMergedBeanDefinition(PersistenceAnnotationBeanPostProcessor.java:296)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyMergedBeanDefinitionPostProcessors(AbstractAutowireCapableBeanFactory.java:830)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:493)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:294)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:585)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:913)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:464)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:631)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:588)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:645)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:508)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:449)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:133)
at javax.servlet.GenericServlet.init(GenericServlet.java:160)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1266)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1185)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:857)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:135)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:987)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:579)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:309)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:679)

有人可以告诉我为什么吗？

我正在开发一个使用spring框架和Hibernate作为ORM的Web应用程序.我想创建一个注册和登录页面.登录时,应为特定用户创建会话(如发送cookie等).由于我刚接触春天,我不知道如何完成这项工作.有人可以给我一个很好的教程吗？谢谢!

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