小编use*_*234的帖子

在JMS API文档中,它说:

public Message receive() throws JMSException

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接收为此消息使用者生成的下一条消息.此调用将无限期地阻塞,直到生成消息或此消息使用者关闭为止.

如果此接收在事务中完成,则使用者会保留该消息,直到事务提交为止.

这里我有三个问题:1.在代码中,我们需要while循环来接收消息吗？喜欢:

while(true){
    Message msg = queue.receive();
    ....
}

2. 什么是交易设置？如何提交交易？像这样:

   boolean transacted = false;
   session = connection.createQueueSession(transacted, Session.AUTO_ACKNOWLEDGE);
   

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3. receiveNoWait()有事务支持吗？如何使用它 ？

谢谢

我正在学习NHibernate,但失败了.我感觉错误消息不准确.

请帮忙 .

错误信息是

The following types may not be used as proxies:
SecondSolution.Domain.Product: method get_Id should be 'public/protected virtual' or 'protected internal virtual'
SecondSolution.Domain.Product: method set_Id should be 'public/protected virtual' or 'protected internal virtual'
SecondSolution.Domain.Product: method get_Name should be 'public/protected virtual' or 'protected internal virtual'
SecondSolution.Domain.Product: method set_Name should be 'public/protected virtual' or 'protected internal virtual'
SecondSolution.Domain.Product: method get_Category should be 'public/protected virtual' or 'protected internal virtual'
SecondSolution.Domain.Product: method set_Category should be 'public/protected virtual' or 'protected internal virtual'
SecondSolution.Domain.Product: …

在ExtJS 3.3.1中,我尝试将comboBox设置为多选,但它不起作用.

请帮忙.

 var mArray = new Array("ALL", "AAA", "BBB");
        var mCombo = new Ext.form.ComboBox({ id: 'ID', fieldLabel: 'ID',
            triggerAction: 'all',
            height: 100, width: 163,
            multiSelect: true,
            store: mArray
        });
        Ext.getCmp('mCombo').setValue("ALL");

在PL/SQL中,下面的代码将失败.它不允许定义varchar2参数的大小.你知道为什么吗？我如何解决它？

create or replace function logMessage(msg varchar2(2000))
return number as
begin
    null;    
    return 1;
end logMessage;
/

错误信息是

1/33 PLS-00103:遇到以下其中一项时遇到符号"("):

:=.),@%default character符号":="代替"("继续.

学习GridBagLayout,这里的问题是,名称标签和combox没有显示在面板的顶部,但我已将其锚点设置为NORTH.为什么？

import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.GridLayout;

import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.WindowConstants;

public class Test2 {    
    public Test2() {
        JFrame frame = new JFrame();
        frame.setTitle("test");
        frame.getContentPane().setLayout(new GridLayout(1,2));
        frame.setSize(800, 600);

        JPanel panel1 = new JPanel();
        panel1.setLayout(new GridBagLayout());

        JLabel label = new JLabel("name");
        GridBagConstraints gridBagConstraints = new GridBagConstraints();   
        gridBagConstraints.anchor = GridBagConstraints.NORTH;
        gridBagConstraints.weightx = 0.0;
        gridBagConstraints.weighty = 0.0;
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 0;
        panel1.add(label, gridBagConstraints);

        String[] petStrings = { "Bird", "Cat", "Dog", "Rabbit", "Pig" };
        JComboBox petList …

在JPA中,我定义了一个将返回String的本机sql,

@NamedNativeQuery(name = "alert", 
query = " select distinct c.accountId from account c ", 
        resultClass = String.class)

错误信息是

org.hibernate.MappingException: Unknown entity: java.lang.String

有线索吗？谢谢

作为一名java开发人员,我需要使用C#.

我熟悉Eclipse IDE.在MS Visual Studio 2010 Ultimate中,如何做到类似？

1. 如果我使用F12查看定义,那么我该如何回到原始文件？

2. 对于接口,如何查看实现此接口或方法的所有类？在Eclipse中,我们只使用CTRL + K.

在SQL Server中,我可以像这样定义局部变量.

declare @id number := 1000

select * from tbl_A where id = @id;
select * from tbl_B where id = @id;

这很方便.我尝试做同样的事情,PL/SQL但它不起作用.

DECLARE id number;
select 1000 into id from dual;

你知道怎么做类似的事吗？最简单的方法是我的目标.

mysql -uroot -proot -e 'create database mydb;'

MySQL版本是

mysql  Ver 14.14 Distrib 5.5.14, for Win64 (x86)

当我运行命令时,它只显示帮助信息.请帮忙.

我正在使用最新的Eclipse在Glassfish 3下开发EJB 3.我在Eclipse中创建了一个新的Glassfish服务器实例,编写了一个简单的EJB,已经部署并成功完成.

现在我写了一个客户端,但它总是给我这样的错误

java.lang.RuntimeException: Orb initialization erorr
    at org.glassfish.enterprise.iiop.api.GlassFishORBHelper.getORB(GlassFishORBHelper.java:148)
    at com.sun.enterprise.naming.impl.SerialContext.getORB(SerialContext.java:365)
    at com.sun.enterprise.naming.impl.SerialContext.getProviderCacheKey(SerialContext.java:372)
    at com.sun.enterprise.naming.impl.SerialContext.getRemoteProvider(SerialContext.java:402)
    at com.sun.enterprise.naming.impl.SerialContext.getProvider(SerialContext.java:347)
    at com.sun.enterprise.naming.impl.SerialContext.lookup(SerialContext.java:504)
    at com.sun.enterprise.naming.impl.SerialContext.lookup(SerialContext.java:455)
    at javax.naming.InitialContext.lookup(InitialContext.java:392)
    at com.client.Test.main(Test.java:22)
Caused by: java.lang.NullPointerException
    at org.glassfish.enterprise.iiop.api.GlassFishORBHelper.getORB(GlassFishORBHelper.java:120)
    ... 8 more
Exception in thread "main" javax.naming.NamingException: Lookup failed for 'helloRemote' in SerialContext[myEnv={java.naming.factory.initial=com.sun.enterprise.naming.SerialInitContextFactory, java.naming.factory.state=com.sun.corba.ee.impl.presentation.rmi.JNDIStateFactoryImpl, java.naming.factory.url.pkgs=com.sun.enterprise.naming} [Root exception is javax.naming.NamingException: Unable to acquire SerialContextProvider for SerialContext[myEnv={java.naming.factory.initial=com.sun.enterprise.naming.SerialInitContextFactory, java.naming.factory.state=com.sun.corba.ee.impl.presentation.rmi.JNDIStateFactoryImpl, java.naming.factory.url.pkgs=com.sun.enterprise.naming} [Root exception is java.lang.RuntimeException: Orb initialization erorr]]
    at com.sun.enterprise.naming.impl.SerialContext.lookup(SerialContext.java:518)
    at com.sun.enterprise.naming.impl.SerialContext.lookup(SerialContext.java:455)
    at javax.naming.InitialContext.lookup(InitialContext.java:392)
    at com.client.Test.main(Test.java:22)
Caused by: javax.naming.NamingException: Unable to acquire …