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protected static connection dogetconnection(datasource datasource, boolean allowsynchronization);
			throws sqlexception {
		
		connectionholder conholder = (connectionholder); transactionsynchronizationmanager.getresource(datasource);;
		if (conholder != null); {
			conholder.requested();;
			return conholder.getconnection();;
		}
		
		connection con = datasource.getconnection();;
		if (allowsynchronization && transactionsynchronizationmanager.issynchronizationactive();); {
						conholder = new connectionholder(con);;
			transactionsynchronizationmanager.bindresource(datasource, conholder);;
			transactionsynchronizationmanager.registersynchronization(new connectionsynchronization(conholder, datasource););;
			conholder.requested();;
		}
		return con;
	}

private static threadlocal resources = new threadlocal();;
public static object getresource(object key); {
		map map = (map); resources.get();;
		if (map == null); {
			return null;
		}
		object value = map.get(key);;
				return value;
	}
public static void bindresource(object key, object value); throws illegalstateexception {
		map map = (map); resources.get();;
				if (map == null); {
			map = new hashmap();;
			resources.set(map);;
		}
		map.put(key, value);;
			}

public void requested(); {
		this.referencecount  ;
	}
	public void released(); {
		this.referencecount--;
	}

if (conholder != null); {
			conholder.requested();;
			return conholder.getconnection();;
		}

protected void docleanupaftercompletion(object transaction); {
		datasourcetransactionobject txobject = (datasourcetransactionobject); transaction;
		// remove the connection holder from the thread.
		transactionsynchronizationmanager.unbindresource(this.datasource);;
		txobject.getconnectionholder();.clear();;
		//...		datasourceutils.closeconnectionifnecessary(con, this.datasource);;
	}

protected static void docloseconnectionifnecessary(connection con, datasource datasource); throws sqlexception {
		if (con == null); {
			return;
		}
		connectionholder conholder = (connectionholder); transactionsynchronizationmanager.getresource(datasource);;
		if (conholder != null && con == conholder.getconnection();); {
			// it's the transactional connection: don't close it.
			conholder.released();;
			return;
		}
		
		// leave the connection open only if the datasource is our
		// special data source, and it wants the connection left open.
		if (!(datasource instanceof smartdatasource); || ((smartdatasource); datasource);.shouldclose(con);); {
			logger.debug("closing jdbc connection");;
			con.close();;
		}
	}

public object execute(preparedstatementcreator psc, preparedstatementcallback action);
			throws dataaccessexception {
		connection con = datasourceutils.getconnection(getdatasource(););;
		//其他代码
	datasourceutils.closeconnectionifnecessary(con, getdatasource(););;
		}
	}

public connection getconnection(); throws sqlexception {
		connection con = datasourceutils.dogetconnection(gettargetdatasource();, true);;
		return gettransactionawareconnectionproxy(con, gettargetdatasource(););;
	}

protected connection gettransactionawareconnectionproxy(connection target, datasource datasource); {
		return (connection); proxy.newproxyinstance(
				connectionproxy.class.getclassloader();,
				new class[] {connectionproxy.class},
				new transactionawareinvocationhandler(target, datasource););;
	}

public object invoke(object proxy, method method, object[] args); throws throwable {
		//...			if (method.getname();.equals(connection_close_method_name);); {
				if (this.datasource != null); {
					datasourceutils.docloseconnectionifnecessary(this.target, this.datasource);;
				}
				return null;
			}
					}

1.   
2. <property name="connection.driver_class">com.mysql.jdbc.driverproperty> <property name="connection.url">jdbc:mysql://localhost:3306/struts?useunicode=true&characterencoding=gbkproperty>   
3. <property name="connection.username">rootproperty>   
4. <property name="connection.password">8888property>   

 com.mysql.jdbc.driver jdbc:mysql://localhost:3306/struts?useunicode=true&characterencoding=gbk  root  8888 

c3p0.min_size">5 c3p0.max_size">30 c3p0.time_out">1800 c3p0.max_statement">50 

dbcp.maxactive">100 dbcp.whenexhaustedaction">1 dbcp.maxwait">60000 dbcp.maxidle">10 dbcp.ps.maxactive">100 dbcp.ps.whenexhaustedaction">1 dbcp.ps.maxwait">60000 dbcp.ps.maxidle">10

dbpool proxool.xml org.hibernate.connection.proxoolconnectionprovider

总的来看 java ee 5 的标注开发方式开来是得到了大家的认可了.

@service 相当于定义 bean, 自动根据 bean 的类名生成一个首字母小写的 bean

@autowired 则是自动注入依赖的类, 它会在类路径中找成员对应的类/接口的实现类, 如果找到多个, 需要用 @qualifier("chineseman") 来指定对应的 bean 的 id.

一定程度上大大简化了代码的编写, 例如一对一的 bean 映射现在完全不需要写任何额外的 bean 定义了.

下面是代码的运行结果:

man.sayhello()=抽你丫的
simpleman said: hi
org.example.englishman@12bcd4b said: fuck you!

代码:

beans.xml

xml version="1.0" encoding="utf-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/xmlschema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemalocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd">
<context:annotation-config/>
<context:component-scan base-package="org.example"/>
beans>

测试类:

import org.example.iman;
import org.example.simpleman;
import org.springframework.context.applicationcontext;
import org.springframework.context.support.classpathxmlapplicationcontext;

public class springtest {
    public static void main(string[] args) {
        applicationcontext ctx = new classpathxmlapplicationcontext("beans.xml");
        simpleman dao = (simpleman) ctx.getbean("simpleman");
        system.out.println(dao.hello());
        iman man = (iman) ctx.getbean("usman");
        system.out.println(man.sayhello());
    }
}

自动探测和注入bean的类:

package org.example;

import org.springframework.beans.factory.annotation.autowired;
import org.springframework.beans.factory.annotation.qualifier;
import org.springframework.stereotype.service;

@service
public class simpleman {
    // 自动注入名称为 man 的 bean
    @autowired(required = false)
    @qualifier("chineseman")
    //@qualifier("usman")
    private iman man;   

    /**
     * @return the man
     */
    public iman getman() {
        return man;
    }

    /**
     * @param man the man to set
     */
    public void setman(iman man) {
        this.man = man;
    }

    public string hello() {
        system.out.println("man.sayhello()=" man.sayhello());
        return "simpleman said: hi";
    }
}

一个接口和两个实现类:

package org.example;

/**
* 抽象的人接口.
* @author beansoft
* @version 1.0
*/
public interface iman {
    /**
     * 打招呼的抽象定义.
     * @return 招呼的内容字符串
     */
    public string sayhello();
}

package org.example;

import org.springframework.stereotype.service;

/**
* 中国人的实现.
* @author beansoft
*/
@service
public class chineseman implements iman {

    public string sayhello() {
        return "抽你丫的";
    }

}

package org.example;

import org.springframework.stereotype.service;

/**
* @author beansoft
* 美国大兵
*/
@service("usman")
// 这里定义了一个 id 为 usman 的 bean, 标注里面的属性是 bean 的 id
public class englishman implements iman {

    public string sayhello() {
        return this " said: fuck you!";
    }

}

jdbctemplate.execute("create table user (user_id integer, name varchar(100))");

jdbctemplate.update("insert into user values('"
  user.getid()   "', '"
  user.getname()   "', '"
  user.getsex()   "', '"
  user.getage()   "')");

jdbctemplate.update("update user set name = ? where user_id = ?", new object[] {name, id});

jdbctemplate.update("insert into user values(?, ?, ?, ?)", new object[] {user.getid(), user.getname(), user.getsex(), user.getage()});

int count = jdbctemplate.queryforint("select count(*) from user");

string name = (string) jdbctemplate.queryforobject("select name from user where user_id = ?", new object[] {id}, java.lang.string.class);

list rows = jdbctemplate.queryforlist("select * from user");

list rows = jdbctemplate.queryforlist("select * from user");
iterator it = rows.iterator();
while(it.hasnext()) {
map usermap = (map) it.next();
system.out.print(usermap.get("user_id")   "\t");
system.out.print(usermap.get("name")   "\t");
system.out.print(usermap.get("sex")   "\t");
system.out.println(usermap.get("age")   "\t");
}

final string id = user.getid();
final string name = user.getname();
final string sex = user.getsex()   "";
final int age = user.getage();
jdbctemplate.update("insert into user values(?, ?, ?, ?)",
new preparedstatementsetter() {
public void setvalues(preparedstatement ps) throws sqlexception {
ps.setstring(1, id);
ps.setstring(2, name);
ps.setstring(3, sex);
ps.setint(4, age);
}
});

final user user = new user();
jdbctemplate.query("select * from user where user_id = ?",
new object[] {id},
new rowcallbackhandler() {
public void processrow(resultset rs) throws sqlexception {
user.setid(rs.getstring("user_id"));
user.setname(rs.getstring("name"));
user.setsex(rs.getstring("sex").charat(0));
user.setage(rs.getint("age"));
}
});

class userrowmapper implements rowmapper {
public object maprow(resultset rs, int index) throws sqlexception {
user user = new user();
user.setid(rs.getstring("user_id"));
user.setname(rs.getstring("name"));
user.setsex(rs.getstring("sex").charat(0));
user.setage(rs.getint("age"));
return user;
}
}
public list findallbyrowmapperresultreader() {
string sql = "select * from user";
return jdbctemplate.query(sql, new rowmapperresultreader(new userrowmapper()));
}

public user getuser(final string id) throws dataaccessexception {
string sql = "select * from user where user_id=?";
final object[] params = new object[] { id };
list list = jdbctemplate.query(sql, params, new rowmapperresultreader(new userrowmapper()));
return (user) list.get(0);
}

 public preparedstatement createpreparedstatement(connection con) throws sqlexception {
return con.preparestatement(sql);
}

 template.update("insert into web_person values(?,?,?)",object[]);

 template.update("insert into web_person values(?,?,?)",new preparedstatementsetter(){ 匿名内部类 只能访问外部最终局部变量
public void setvalues(preparedstatement ps) throws sqlexception {
ps.setint(index  ,3);
});

 public void setvalues(preparedstatement ps) throws sqlexception {
ps.setint(index  ,3);
}

 public object maprow(resultset rs, int arg1) throws sqlexception {   int表当前行数
person.setid(rs.getint("id"));
}
list template.query("select * from web_person where id=?",object[],rowmapper);

(一)新建一个java bean(hellobean.java)

java 代码

1. package chb.demo.vo;   
2.   
3. public class hellobean {   
4.  private string helloworld;   
5.   
6.  public string gethelloworld() {   
7.   return helloworld;   
8.  }   
9.   
10.  public void sethelloworld(string helloworld) {   
11.   this.helloworld = helloworld;   
12.  }   
13. }   
14.   

(二)构造一个配置文件(beanconfig.xml)

xml 代码

1. xml version="1.0" encoding="utf-8"?>  
2. >  
3. <beans>  
4.  <bean id="hellobean" class="chb.demo.vo.hellobean">  
5.   <property name="helloworld">  
6.    <value>hello!chb!value>  
7.   property>  
8.  bean>  
9. beans>  

(三)读取xml文件

1.利用classpathxmlapplicationcontext

java 代码

1. applicationcontext context = new classpathxmlapplicationcontext("beanconfig.xml");   
2. hellobean hellobean = (hellobean)context.getbean("hellobean");   
3. system.out.println(hellobean.gethelloworld());  

2.利用filesystemresource读取

java 代码

1. resource rs = new filesystemresource("d:/software/tomcat/webapps/springwebdemo/web-inf/classes/beanconfig.xml");   
2.   beanfactory factory = new xmlbeanfactory(rs);   
3.   hellobean hellobean = (hellobean)factory.getbean("hellobean");\   
4.   system.out.println(hellobean.gethelloworld());   

 值得注意的是：利用filesystemresource，则配置文件必须放在project直接目录下，或者写明绝对路径，否则就会抛出找不到文件的异常

这里介绍两种技术：利用spring读取properties 文件和利用java.util.properties读取

(一)利用spring读取properties 文件

我们还利用上面的hellobean.java文件，构造如下beanconfig.properties文件:

properties 代码

1. hellobean.class=chb.demo.vo.hellobean   
2. hellobean.helloworld=hello!chb!  

属性文件中的"hellobean"名称即是bean的别名设定，.class用于指定类来源。

然后利用org.springframework.beans.factory.support.propertiesbeandefinitionreader来读取属性文件

java 代码

1. beandefinitionregistry reg = new defaultlistablebeanfactory();   
2.  propertiesbeandefinitionreader reader = new propertiesbeandefinitionreader(reg);   
3.  reader.loadbeandefinitions(new classpathresource("beanconfig.properties"));   
4.  beanfactory factory = (beanfactory)reg;   
5.  hellobean hellobean = (hellobean)factory.getbean("hellobean");   
6.  system.out.println(hellobean.gethelloworld());   

 

(二)利用java.util.properties读取属性文件

比如，我们构造一个ipconfig.properties来保存服务器ip地址和端口，如：

properties 代码

1. ip=192.168.0.1   
2. port=8080  

则，我们可以用如下程序来获得服务器配置信息：

java 代码

1. inputstream inputstream = this.getclass().getclassloader().getresourceasstream("ipconfig.properties");   
2.   properties p = new properties();   
3.   try {   
4.    p.load(inputstream);   
5.   } catch (ioexception e1) {   
6.    e1.printstacktrace();   
7.   }   
8. system.out.println("ip:" p.getproperty("ip") ",port:" p.getproperty("port"));