Spring学习心得(二)——日志和数据库

上一篇介绍了Spring的基本配置，本节介绍使用Spring生成日志和操作数据库的实战。

第一步，配置spring的log4j日志。

    　　1.引入log4j所需要的jar包，在上一篇博客的附件中包含log4j-1.2.15.jar，如果还没有引入，直接拷贝到“WebRoot/WEB-INF/lib/”中即可。

　２.配置web.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns="http://xmlns.jcp.org/xml/ns/javaee"
	xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
	id="WebApp_ID" version="3.1">
	<display-name>MySpring</display-name>
	<context-param>
		<param-name>contextConfigLocation</param-name>
		<param-value>/WEB-INF/spring*.xml</param-value>
	</context-param>
	<context-param>
		<param-name>webAppRootKey</param-name>
		<param-value>myProject.root</param-value>
	</context-param>
	<context-param>
		<param-name>log4jConfigLocation</param-name>
		<param-value>/WEB-INF/conf/log4j.properties</param-value>
	</context-param>
	<listener>
		<listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
	</listener>
	<listener>
		<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
	</listener>




	<servlet>
		<servlet-name>test</servlet-name>
		<servlet-class>servlet.TestServlet</servlet-class>
	</servlet>
	<servlet-mapping>
		<servlet-name>test</servlet-name>
		<url-pattern>*.lzy</url-pattern>
	</servlet-mapping>


	<welcome-file-list>
		<welcome-file>index.html</welcome-file>
		<welcome-file>index.htm</welcome-file>
		<welcome-file>index.jsp</welcome-file>
		<welcome-file>default.html</welcome-file>
		<welcome-file>default.htm</welcome-file>
		<welcome-file>default.jsp</welcome-file>
	</welcome-file-list>
</web-app>

 这一步的作用就是让spring帮忙照料下log4j的配置文件管理,  如果跳过第二步, 这里其实就和spring没什么关系,就是单独使用log4j了. (虽然后台还有将log4j交由spring容器接管之类的,我们不用关心了.)

　3.写log4j的配置文件（本人是小白，在网上抄了一个)

在“WebRoot/WEB-INF/lib/”路径下建立conf文件夹，并新建log4j.properties文件

log4j.rootLogger= DEBUG, CONSOLE
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender

#org.apache.log4j.HTMLLayout
#org.apache.log4j.PatternLayout
#org.apache.log4j.SimpleLayout
#org.apache.log4j.TTCCLayout
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=%-4r %-5p [%t] %37c %3x - %m%n

#log4j.appender.FILE=org.apache.log4j.DailyRollingFileAppender
#log4j.appender.FILE.layout = org.apache.log4j.PatternLayout
#log4j.appender.FILE.layout.ConversionPattern=%-d{yyyy-MM-dd HH:mm:ss} [%c]-[%p] - %m%n
#\u8FD9\u91CC\u7684${myProject.root}\u662F\u5728\u7B2C\u4E8C\u6B65\u4E2D\u914D\u7F6E\u51FA\u6765\u7684. \u4E5F\u53EF\u4EE5\u5199\u7EDD\u5BF9\u8DEF\u5F84
#log4j.appender.FILE.File=${myProject.root}/log/sqmslog.log

#log4j.appender.FILE2 = org.apache.log4j.RollingFileAppender
#log4j.appender.FILE2.MaxFileSize = 500KB

 

log4j.logger.org.springframework=WARN   
  
log4j.logger.test=DEBUG

第二部，spring操作数据库数据库。

 　　　1.把Spring操作数据库依赖的一些jar包导入，需要的jar包有asm、beans、context、core、expression、web、jdbc、transaction、dbcp、pool上一篇文章附件中有所需要的大部分jar包，本文附件中补全了需要的所有jar包，可以根据需要选择合适的版本使用。

　2.编辑spring配置文件。

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://www.springframework.org/schema/beans
 http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">


	<bean id="TestBo" class="servlet.TestBo">
		<property name="name" value="123"></property>
		<property name="dataSource" ref="dataSource"  />  
	</bean>

	<bean id="TestAction" class="servlet.TestAction">
		<property name="name" value="abc"></property>
		<property name="testbo" ref="TestBo"></property>
	</bean>


	<!-- 数据库设置 -->
	<bean
		class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
		<property name="locations" value="/WEB-INF/conf/jdbc.properties" />
	</bean>
	<bean id="dataSource" class="org.apache.commons.dbcp2.BasicDataSource"
		destroy-method="close">
		<property name="driverClassName" value="${jdbc.driverClassName}" />
		<property name="url" value="${jdbc.url}" />
		<property name="username" value="${jdbc.username}" />
		<property name="password" value="${jdbc.password}" />
	</bean>


</beans>

 　这里使用的是将数据库信息写在文件jdbc.properties里, 你也可以将信息直接写在dataSource的bean属性里(将第一个bean去掉),

　3.在“WebRoot/WEB-INF/lib/conf”文件夹下建立jdbc.properties文件。

jdbc.driverClassName=org.gjt.mm.mysql.Driver
jdbc.url=jdbc:mysql://127.0.0.1:3306/mysql?useUnicode=true
jdbc.username=root
jdbc.password=***

第三部，测试。

TestServlet.java

package servlet;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.context.ApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;

/**
 * Servlet implementation class TestServlet
 */
@WebServlet("/TestServlet")
public class TestServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
	TestAction ta;
    /**
     * @see HttpServlet#HttpServlet()
     */
    public TestServlet() {
        super();
        // TODO Auto-generated constructor stub
    }
    
    /**
     * service
     * @throws IOException 
     */
    public void service(HttpServletRequest request,HttpServletResponse response) throws IOException{
    	PrintWriter pw=response.getWriter();
    	pw.write(ta.getTestbo().getName());
    	pw.flush();
    	pw.close();
    }

    public void init(ServletConfig servletConfig)
    	      throws ServletException{
    	     servletConfig.getServletContext();
    	     ApplicationContext ctx = WebApplicationContextUtils.getWebApplicationContext(servletConfig.getServletContext());
    	     this.ta = (TestAction) ctx.getBean("TestAction");
    	     this.ta.sayHello();
    	   System.out.println("TestServlet init");
//    	     TestAction ta = new TestAction();
//    	     ta.sayHello();
    	    }
}

 TestBo.java

package servlet;


import javax.sql.DataSource;

import org.springframework.jdbc.core.JdbcTemplate;

public class TestBo {

	private String name;

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	private JdbcTemplate jdbcTemplate;
	private DataSource dataSource;
	
	public DataSource getDataSource() {
		return dataSource;
	}

	public void setDataSource(DataSource dataSource) {
		this.jdbcTemplate = new JdbcTemplate(dataSource);
		System.out.println(jdbcTemplate+"----");
	}

	public int getindex() {
		int countOfActorsNamedJoe = this.jdbcTemplate.queryForInt(
				"select count(*) from help_topic");
		return countOfActorsNamedJoe;
	}
}

 TestAction.java

package servlet;

public class TestAction {

	private String name;

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}
	
	private TestBo testbo;
	public void sayHello() {
		// TODO Auto-generated method stub
		System.out.println(name+"  "+testbo.getindex());
	}

	public TestBo getTestbo() {
		return testbo;
	}

	public void setTestbo(TestBo testbo) {
		this.testbo = testbo;
	}
	

	
}

　后记，本人在操作数据库时碰到一个莫名其妙的问题：

严重: StandardWrapper.Throwable
java.lang.AbstractMethodError: com.mysql.jdbc.Connection.isValid(I)Z
	at org.apache.commons.dbcp2.DelegatingConnection.isValid(DelegatingConnection.java:914)
	at org.apache.commons.dbcp2.PoolableConnection.validate(PoolableConnection.java:283)
	at org.apache.commons.dbcp2.PoolableConnectionFactory.validateConnection(PoolableConnectionFactory.java:357)
	at org.apache.commons.dbcp2.BasicDataSource.validateConnectionFactory(BasicDataSource.java:2304)
	at org.apache.commons.dbcp2.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:2287)
	at org.apache.commons.dbcp2.BasicDataSource.createDataSource(BasicDataSource.java:2038)
	at org.apache.commons.dbcp2.BasicDataSource.getConnection(BasicDataSource.java:1533)
	at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111)
	at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77)
	at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:382)
	at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:456)
	at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:464)
	at org.springframework.jdbc.core.JdbcTemplate.queryForObject(JdbcTemplate.java:472)
	at org.springframework.jdbc.core.JdbcTemplate.queryForObject(JdbcTemplate.java:477)
	at org.springframework.jdbc.core.JdbcTemplate.queryForInt(JdbcTemplate.java:486)
	at servlet.TestBo.getindex(TestBo.java:33)
	at servlet.TestAction.sayHello(TestAction.java:18)
	at servlet.TestServlet.init(TestServlet.java:48)
	at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1231)
	at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1144)
	at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:817)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:135)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
	at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
	at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:617)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
	at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:668)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1527)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1484)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:745)

 这是因为mysql-connector-java-5.0.5-bin.jar版本和dbpc版本不匹配，我把mysql-connector-java-5.0.5-bin.jar换成了mysql-connector-java-5.1.26-bin.jar就解决了。