Entity Bean的开发 和 Jboss 数据源的配置

//-------------- 实体bean 的开发

1:实体bean 属于Java持久化规范 (简称JPA)里的技术,实体bean通过元数据在javabean和数据库表之间建立映射关系,然后java程序员就可以随性所欲 使用面向对象的编程思想来操作数据了.

2:JPA的出现主要是为了简化现有的持久化开发工作和整合ORM技术.

3:目前实现了JPA规范过的主流产品有Hibernate TopLink OpenJPA ibatis mybatis . 

4:在 jboss中采用HIbernate 最为其持久化实现产品.

------配置 jboss 的数据源

1.数据库连接对象的创建是很耗性能的,配置数据源后可以提升性能..

jboss5.0  和 jboss  6.0 一样 

EBJ 提供了模版啦!!
 E:\jboss-5.0.0.GA\docs\examples\jca 里面就可以看到很多数据的配置模版 
   比如mysql 的配置模版  mysql-ds.xml

然后修改
比如
    <jndi-name>MySqlDS</jndi-name>
    <connection-url>jdbc:mysql://mysql-hostname:3306/jbossdb</connection-url>
    <driver-class>com.mysql.jdbc.Driver</driver-class>
    <user-name>x</user-name>
    <password>y</password>

第一个:修改 jndi名称
第二个Ip地址: localhost:3306 
第三个数据名称:  jbossdb---> spdb1 (创建数据库的时候一般使用 UTF-8编码)
第四个用户名:x--->root
第五个密码y:123456

注意:
数据源的文件的取名:必须要以 -ds 结尾

发布之前 还要注意 "数据库的驱动类" 
复制到  E:\jboss-5.0.0.GA\server\default\lib

完成后 将修改好的 mysql-ds.xml 拷贝到 
E:\jboss-5.0.0.GA\server\default\deploy

此时就会看到 数据源的jndi名称为: java:MySqlDS

到jboss控制后台 查看 数据源 
http://localhost:8080/jmx-console/  --->jboss.jca---name:java:MySqlDS;

然后要注意的一个 就是 查看数据源一些属性的配置
查看 连接池的 属性 点击进去
name=JbossOracleDS,service=ManagedConnectionPool

MaxSize :最大可以数量 默认 20 条
InUseConnectionCount :正在使用的连接统计.
MinSize :最小的连接数量
BlockingTimeoutMillis:最大等待时间  30秒

修改后 点击  Apply Changes    只用在jboss 运行时候就生效  关闭 就会丢失修改后的值  要永久的修改 就要修改数据源文件   mysql-ds.xml 添加参数

<min-pool-size>1</min-pool-size>
<min-pool-size>50</min-pool-size>

注意 
正在使用人数 和 数据源的最大连接数 如果数量 一直是满的 就要考虑 是否扩大连接数了

--给出一个 oralce的配置  oracle-ds.xml

<?xml version="1.0" encoding="UTF-8"?>

<!-- ===================================================================== -->
<!--                                                                       -->
<!--  JBoss Server Configuration                                           -->
<!--                                                                       -->
<!-- ===================================================================== -->

<!-- $Id: oracle-ds.xml 23720 2004-09-15 14:37:40Z loubyansky $ -->
<!-- ==================================================================== -->
<!--  Datasource config for Oracle originally from Steven Coy             -->
<!-- ==================================================================== -->


<datasources>
  <local-tx-datasource>
    <jndi-name>JbossOracleDS</jndi-name>
    <connection-url>jdbc:oracle:thin:@192.168.1.242:1521:ora11g</connection-url>
	<!--

		Here are a couple of the possible OCI configurations.
		For more information, see http://otn.oracle.com/docs/products/oracle9i/doc_library/release2/java.920/a96654/toc.htm

	<connection-url>jdbc:oracle:oci:@youroracle-tns-name</connection-url>
		or
	<connection-url>jdbc:oracle:oci:@(description=(address=(host=youroraclehost)(protocol=tcp)(port=1521))(connect_data=(SERVICE_NAME=yourservicename)))</connection-url>

		Clearly, its better to have TNS set up properly.
	 -->
    <driver-class>oracle.jdbc.driver.OracleDriver</driver-class>
    <user-name>bjdata</user-name>
    <password>bjdata</password>
    <!-- Uses the pingDatabase method to check a connection is still valid before handing it out from the pool -->
    <!--valid-connection-checker-class-name>org.jboss.resource.adapter.jdbc.vendor.OracleValidConnectionChecker</valid-connection-checker-class-name-->
    <!-- Checks the Oracle error codes and messages for fatal errors -->
    <exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.OracleExceptionSorter</exception-sorter-class-name>
        <!-- sql to call when connection is created
        <new-connection-sql>some arbitrary sql</new-connection-sql>
        -->

        <!-- sql to call on an existing pooled connection when it is obtained from pool - the OracleValidConnectionChecker is prefered
        <check-valid-connection-sql>some arbitrary sql</check-valid-connection-sql>
        -->

      <!-- corresponding type-mapping in the standardjbosscmp-jdbc.xml (optional) -->
      <metadata>
         <type-mapping>Oracle10g</type-mapping>
      </metadata>
  </local-tx-datasource>

</datasources>

添加JPA的持久化配置文件 persistence.xml 类是 hibernate

<!--根据JPA的规范的要求,在实体bean的应用中,我们需要在应用的类路径下的META-INF目录加入持久化配置文件 persistence.xml-->

<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/persistence 
    http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd" 
    version="1.0">
<!-- 持久化单元  (可以配置多个) 
	JTA: 全局事物 ejb默认的事务类型 可以不用设置
	RESOURCE_LOCAL:本地事务
	添加数据源 :提高性能
-->
<persistence-unit name="mytest" transaction-type="JTA" >
	<!-- 配置的jboss 数据源jndi名称  -->
	<jta-data-source>java:JbossOracleDS</jta-data-source>
	
	<properties>
		<property name="hibernate.dialect" value="org.hibernate.dialect.Oracle10gDialect"/>
		<!-- 自动生存表接口 
		create-drop:启动创建表,程序 卸载的时候会删除表结构  测试的有用
		create:启动创建,  卸载的时候不会删除
		update:保留数据库的数据,如果添加新的字段后,会同步到数据库中.
		<property name="hibernate.hbm2ddl.auto" value="create-drop"/>
		-->
		<!-- 打印 sql语句 -->
		<property name="hibernate.show_sql" value="true"/>
		<!--格式化sql语句 -->
		<property name="hibernate.format_sql" value="true"/>
	</properties>
</persistence-unit>   

</persistence>

jndi.properties

java.naming.factory.initial=org.jnp.interfaces.NamingContextFactory
java.naming.provider.url=localhost:1099	

---编写 实体bean
采用注解 配置 ORM　映射关系


BiAnswer.java

package com.sh.ejb3.bean;

import java.io.Serializable;
import java.util.Date;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity //@Entity(name="xxx") 可以修改
@Table(name="bi_answer")
public class BiAnswer implements Serializable{

 private static final long serialVersionUID = 5687494436224059560L;
 
 private Integer id;
 @Column(name="answer",length=300,nullable=true)
 private String answer;
 private String correct;
 private Integer sortid;
 private Integer qid;
 private Date createtime;
 
public BiAnswer() {
}
public BiAnswer(Integer id,String answer,Integer qid) {
	this.id=id;
	this.answer=answer;
	this.qid=qid;
}

@Id @Column(name="id")  //这些注解 只能标注在 get() 方法上 不能在set 上  还可以标注 字段上
public Integer getId() {
	return id;
}
public void setId(Integer id) {
	this.id = id;
}

public String getAnswer() {
	return answer;
}
public void setAnswer(String answer) {
	this.answer = answer;
}
@Column(name="correct",length=1,nullable=true)
public String getCorrect() {
	return correct;
}
public void setCorrect(String correct) {
	this.correct = correct;
}
@Column(name="sortid",length=10,nullable=true)
public Integer getSortid() {
	return sortid;
}
public void setSortid(Integer sortid) {
	this.sortid = sortid;
}
@Column(name="qid",length=10,nullable=true)
public Integer getQid() {
	return qid;
}
public void setQid(Integer qid) {
	this.qid = qid;
}
@Column(name="createtime",nullable=true)
public Date getCreatetime() {
	return createtime;
}
public void setCreatetime(Date createtime) {
	this.createtime = createtime;
}

@Override
public int hashCode() {
	final int prime = 31;
	int result = 1;
	result = prime * result + ((id == null) ? 0 : id.hashCode());
	return result;
}
@Override
public boolean equals(Object obj) {
	if (this == obj)
		return true;
	if (obj == null)
		return false;
	if (getClass() != obj.getClass())
		return false;
	BiAnswer other = (BiAnswer) obj;
	if (id == null) {
		if (other.id != null)
			return false;
	} else if (!id.equals(other.id))
		return false;
	return true;
}
}

BiAnswerService.java

package com.sh.ejb3.service;

import java.util.List;

import com.sh.ejb3.bean.BiAnswer;

public interface BiAnswerService {

	public void save (BiAnswer answer);
	public void update(BiAnswer answer);
	public void delete(Integer answerid);
	public BiAnswer getAnswer(Integer answerid);
	public List<BiAnswer> getAnswers();
}

BiAnswerServiceBean.java

package com.sh.ejb3.service.impl;

import java.util.List;

import javax.ejb.Remote;
import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.PersistenceContextType;

import com.sh.ejb3.bean.BiAnswer;
import com.sh.ejb3.service.BiAnswerService;
@Stateless
@Remote(BiAnswerService.class)
public class BiAnswerServiceBean implements BiAnswerService {
	
	//使用实体管理器 如果只有一个 持久化单元 unitName可以不用配置 否则有多个的话 就需要配置
	@PersistenceContext(unitName="mytest") EntityManager em;
	
	@Override
	public void save(BiAnswer answer) {
		// TODO Auto-generated method stub
		em.persist(answer); //只将持久化字段保存到数据库中对应的字段
	}

	@Override
	public void update(BiAnswer answer) {
		// TODO Auto-generated method stub
		em.merge(answer);  //answer 为 游离状态 而且 进行了修改   使用 merge 
	}

	@Override
	public void delete(Integer answerid) {
		// TODO Auto-generated method stub
		//getReference 返回的是一个 代理对象  一般都是 懒加载  和 Hibernate中  一样
		em.remove(em.getReference(BiAnswer.class, answerid));  //处于托管状态
	}

	@Override
	public BiAnswer getAnswer(Integer answerid) {
		// TODO Auto-generated method stub
		return em.find(BiAnswer.class, answerid); //如果没有找到就返回一个null
	}

	@SuppressWarnings("unchecked")  //终止警告
	@Override
	public List<BiAnswer> getAnswers() {
		// TODO Auto-generated method stub   
		//注意 采用的 HQL 语句 注意 BiAnswer 的类的简单名称  可以通过 @Entity(name="xxx") 修改
		return em.createQuery("SELECT o from BiAnswer o").getResultList();
	}

}

BiAnswerServiceTest.java

package junit.test;

import static org.junit.Assert.fail;

import java.util.List;

import javax.naming.InitialContext;

import org.junit.BeforeClass;
import org.junit.Test;

import com.sh.ejb3.bean.BiAnswer;
import com.sh.ejb3.service.BiAnswerService;

public class BiAnswerServiceTest {
	private static BiAnswerService answerService; 
	@BeforeClass
	public static void setUpBeforeClass() throws Exception {
		try {
			//不采用硬编码  就可以直接 添加 一个jndi.properties  会自动从java类路径中 去寻找  服务器的配置文件
			InitialContext ctx=new InitialContext();//InitialContext(props);
			answerService=(BiAnswerService)ctx.lookup("BiAnswerServiceBean/remote"); //测试  远程接口
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	@Test
	public void testSave() {
		answerService.save(new BiAnswer(1050,"5等南瓜多少分?",1040));
	}

	@Test
	public void testUpdate() {
		BiAnswer answer=answerService.getAnswer(1048);
		answer.setAnswer("家园被污染了!!呜呜");
		answerService.update(answer);
	}
}

--使用 Ant 进行编译
build.xml

<?xml version="1.0" encoding="UTF-8"?>
<!-- ====================================================================== 
     2013-2-25 下午1:53:33                                                        

     project    
     description
                   
     Bin                                                                
     ====================================================================== -->
<project name="EntityBean" basedir=".">
    <description> 
            description
    </description>
	<!-- 设置项目原目录 -->
	<property name="src.dir" value="${basedir}\src" />
	<!-- 获取环境变量 -->
	<property environment="env"/>
	<property name="jboss.home" value="${env.JBOSS_HOME}"/>
	<property name="jboss.server.config" value="default"/>
	<property name="build.dir" value="${basedir}\build"/>
    
	<!-- 引入 jboss client 下的 所有jar -->
	<path id="build.classpath">
		<fileset dir="${jboss.home}\client">
			<include name="*.jar"/>
		</fileset>
		<!-- 讲编译过后的路径加入到 path中去 方便   接口和实现的引用 -->
		<pathelement location="${build.dir}"/>
	</path>
	
	
    <target name="prepare" description="创建build目录">
		<delete dir="${build.dir}"/>
    	<mkdir dir="${build.dir}"/>
    </target>

    <!-- - - - - - - - - - - - - - - - - - 
          target: compile                      
         - - - - - - - - - - - - - - - - - -->
    <target name="compile" depends="prepare" description="编译">
    	<javac srcdir="${src.dir}" destdir="${build.dir}" includeantruntime="false" includes="com/**">
    		<classpath refid="build.classpath"/>
    	</javac>
    </target>
	
	<!-- ================================= 
          target: ejbjar              
         ================================= -->
    <target name="ejbjar" depends="compile" description="创建EJB发布包">
        <jar jarfile="${basedir}\${ant.project.name}.jar">
        	<fileset dir="${build.dir}">
        		<include name="**/*.class"/>
        	</fileset>
        	<!-- 将原目录下META-INF下的所有文件都打包到 jar文件的META-INF下-->
        	<metainf dir="${src.dir}\META-INF"></metainf>
        </jar>
    </target>

	<!-- ================================= 
          target: deploy              
         ================================= -->
    <target name="deploy" depends="ejbjar" description="发布EJB">
        <copy file="${basedir}\${ant.project.name}.jar" todir="${jboss.home}\server\${jboss.server.config}\deploy"/>
    </target>
	
	<!-- - - - - - - - - - - - - - - - - - 
          target: undeploy                      
         - - - - - - - - - - - - - - - - - -->
    <target name="undeploy" description="卸载EJB">
         <delete file="${jboss.home}\server\${jboss.server.config}\deploy\${ant.project.name}.jar"/>   
    </target>




</project>