----------------------------------------------一.WEB項目的執行流程---------------------------------
1.web項目的運行流程大致如下：    
    啟動tomcat，先到web.xml里面查看<context-param><listener><filter><servlet>等等幾個tag，查看里面的配置，查找相應的配置文件。
如下列文件所示：
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="  <display-name>SpringMVC12</display-name>
  <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>
 
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath*:config/springAnnotation-*.xml</param-value>
  </context-param>
 
 
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
 
  <servlet>
   <servlet-name>springMVC</servlet-name>
   <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
     <param-name>contextConfigLocation</param-name>
     <param-value>classpath*:config/springAnnotation-servlet.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
 
  <filter>
  <filter-name>encodingFilter</filter-name>
  <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
  <init-param>
   <param-name>encoding</param-name>
   <param-value>UTF-8</param-value>
  </init-param>
  <init-param>
   <param-name>forceEncoding</param-name>
   <param-value>true</param-value>
  </init-param>
 </filter>
 <!-- encoding filter for jsp page -->
 <filter-mapping>
  <filter-name>encodingFilter</filter-name>
  <url-pattern>/*</url-pattern>
 </filter-mapping>
 
  <servlet-mapping>
   <servlet-name>springMVC</servlet-name>
   <url-pattern>/</url-pattern>
  </servlet-mapping>
 
  <filter>
    <filter-name>openSession</filter-name>
    <filter-class>org.springframework.orm.hibernate4.support.OpenSessionInViewFilter</filter-class>
  </filter>
 
  <filter-mapping>
   <filter-name>openSession</filter-name>
   <url-pattern>/*</url-pattern>
  </filter-mapping>
</web-app>

首先查看那幾個標簽，找到對應的配置文件，如<context-param>中配置的classpath*:config/springAnnotation-*.xml。


---------------------------------------2.到配置文件查看相關信息----------------------------------------------
（1）<context-param>里的classpath*:config/springAnnotation-*.xml，即在config目錄下匹配springAnnotation-*.xml的文件



（1.1）查看springAnnotation-core.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN 2.0//EN" "<!ENTITY contextInclude SYSTEM "org/springframework/web/context/WEB-INF/contextInclude.xml">
]>

<beans>
 
 <import resource="classpath*:com/zyh/web/controller/spring/springAnnotation-import.xml"/>
</beans>

對應的路徑如下com/zyh/web/controller/spring/springAnnotation-import.xml
（1.2）查看springAnnotation-import.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN 2.0//EN" "<!ENTITY contextInclude SYSTEM "org/springframework/web/context/WEB-INF/contextInclude.xml">
]>

<beans>
 <bean id="userDao" class="com.zyh.web.controller.dao.UserDAO">
  <property name="sessionFactory" ref="sessionFactory"></property>
 </bean>
 
 <bean id="userManagerBase" class="com.zyh.web.controller.service.UserManager">
  <property name="userDao" ref="userDao"></property>
 </bean>
 
 <bean id="userManager" parent="transactionBese">
  <property name="target" ref="userManagerBase"></property>
 </bean>
 
</beans>

對應關于就已經配置在容器里面了。
（2.1）查看springAnnotation-hibernate.xml（配置數據源，sessionFactory，和事物）

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN 2.0//EN" "<!ENTITY contextInclude SYSTEM "org/springframework/web/context/WEB-INF/contextInclude.xml">
]>

<beans>
 <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
  <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
  <property name="url" value="jdbc:mysql://localhost/test1?useUnicode=true"/>
  <property name="username" value="root"/>
  <property name="password" value="root"/>
 </bean>
 
 <bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
  <property name="dataSource" ref="dataSource"/>
  <property name="hibernateProperties">
   <props>
    <prop key="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</prop>
    <prop key="hibernate.hbm2ddl.auto">update</prop>
                <prop key="hibernate.show_sql">true</prop>
                <prop key="hiberante.format_sql">true</prop>
   </props>
  </property>
  <property name="configLocations">
   <list>
    <value>
     classpath*:com/zyh/web/controller/hibernate/hibernate.cfg.test.xml
    </value>
   </list>
  </property>
 </bean>
 
 <bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
  <property name="sessionFactory" ref="sessionFactory"></property>
 </bean>
 
 <bean id="transactionBese" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean" lazy-init="true" abstract="true">
  <property name="transactionManager" ref="transactionManager"></property>
  <property name="transactionAttributes">
   <props>
    <prop key="add*">PROPAGATION_REQUIRED,-Exception</prop>
    <prop key="update*">PROPAGATION_REQUIRED,-Exception</prop>
    <prop key="insert*">PROPAGATION_REQUIRED,-Exception</prop>
    <prop key="modify*">PROPAGATION_REQUIRED,-Exception</prop>
    <prop key="delete*">PROPAGATION_REQUIRED,-Exception</prop>
    <prop key="get*">PROPAGATION_NEVER</prop>
   </props>
  </property>
 </bean>
</beans>

 配置的對應的 classpath*:com/zyh/web/controller/hibernate/hibernate.cfg.test.xml
    

（3）springAnnotation-servlet.xml，內容如下

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns=" xmlns:context=" xmlns:p=" xmlns:mvc=" xmlns:xsi=" xsi:schemaLocation="http://www.springframework.org/schema/beans 
      http://www.springframework.org/schema/beans/spring-beans-3.0.xsd 
      http://www.springframework.org/schema/context 
      http://www.springframework.org/schema/context/spring-context.xsd 
      http://www.springframework.org/schema/mvc 
           <!-- 注解掃描包 -->
 <context:component-scan base-package="com.zyh.web.controller" />
 <!-- 開啟注解 -->
 
 <mvc:annotation-driven/>
 
 <!-- <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" />
 <bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping"></bean> -->
 <!-- 靜態資源訪問 -->
  <mvc:resources location="/img/" mapping="/img/**"/> 
  <mvc:resources location="/js/" mapping="/js/**"/>  
 

 <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
  <property name="prefix" value="/"></property>
  <property name="suffix" value=".jsp"></property>
 </bean>
 
 <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    <property name="defaultEncoding" value="utf-8" />
       <property name="maxUploadSize" value="10485760000" />
       <property name="maxInMemorySize" value="40960" />
 </bean>
 </beans> 

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns=" xmlns:context=" xmlns:p=" xmlns:mvc=" xmlns:xsi=" xsi:schemaLocation="http://www.springframework.org/schema/beans 
      http://www.springframework.org/schema/beans/spring-beans-3.0.xsd 
      http://www.springframework.org/schema/context 
      http://www.springframework.org/schema/context/spring-context.xsd 
      http://www.springframework.org/schema/mvc 
           <!-- 注解掃描包 -->
<context:component-scan base-package="com.zyh.web.controller" />
<!-- 開啟注解 -->

<mvc:annotation-driven/>

<!-- <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter" />
<bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping"></bean> -->
<!-- 靜態資源訪問 -->
  <mvc:resources location="/img/" mapping="/img/**"/> 
  <mvc:resources location="/js/" mapping="/js/**"/>  

<bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
  <property name="prefix" value="/"></property>
  <property name="suffix" value=".jsp"></property>
</bean>

<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    <property name="defaultEncoding" value="utf-8" />
       <property name="maxUploadSize" value="10485760000" />
       <property name="maxInMemorySize" value="40960" />
</bean>
</beans> 

springAnnotation-hibernate.xml<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN 2.0//EN" "<!ENTITY contextInclude SYSTEM "org/springframework/web/context/WEB-INF/contextInclude.xml">
]>

<beans>
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
  <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
  <property name="url" value="jdbc:mysql://localhost/test1?useUnicode=true"/>
  <property name="username" value="root"/>
  <property name="password" value="root"/>
</bean>

<bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
  <property name="dataSource" ref="dataSource"/>
  <property name="hibernateProperties">
   <props>
    <prop key="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</prop>
    <prop key="hibernate.hbm2ddl.auto">update</prop>
                <prop key="hibernate.show_sql">true</prop>
                <prop key="hiberante.format_sql">true</prop>
   </props>
  </property>
  <property name="configLocations">
   <list>
    <value>
     classpath*:com/zyh/web/controller/hibernate/hibernate.cfg.test.xml
    </value>
   </list>
  </property>
</bean>

<bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
  <property name="sessionFactory" ref="sessionFactory"></property>
</bean>

<bean id="transactionBese" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean" lazy-init="true" abstract="true">
  <property name="transactionManager" ref="transactionManager"></property>
  <property name="transactionAttributes">
   <props>
    <prop key="add*">PROPAGATION_REQUIRED,-Exception</prop>
    <prop key="update*">PROPAGATION_REQUIRED,-Exception</prop>
    <prop key="insert*">PROPAGATION_REQUIRED,-Exception</prop>
    <prop key="modify*">PROPAGATION_REQUIRED,-Exception</prop>
    <prop key="delete*">PROPAGATION_REQUIRED,-Exception</prop>
    <prop key="get*">PROPAGATION_NEVER</prop>
   </props>
  </property>
</bean>
</beans>

這個寫的有點亂，理清思路，其實很簡單，就是配置spring容器,里面掃描了所有的bean及一些依賴關系，hibernate配置數據源建立數據庫連接，SessionFactory用于管理數據庫，還有就是Springmvc用于控制視圖與后臺之間的頁面轉向，傳遞數據，發送請求。
配置工作就到此結束，然后就是寫bean,dao,service,control與聯系配置文件的對應關系，實際開發中當然不會把配置文件都寫好才來寫java代碼。我的做法是同時進行，漏了就相應的加上。

-----------------------------------------------------------3對應的實現--------------------------------------
3.1 為了簡單，我們建立一個單表的添刪改查，就一個對象吧User，對應的表T_User,里面有userName和age兩個屬性，當然還要建立一個主鍵id,如下列代碼所示:
com.zyh.web.controller.entity.User

package com.zyh.web.controller.entity;

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

import org.hibernate.annotations.GenericGenerator;

@Entity
@Table(name="T_USER")
public class User {

 @GeneratedValue(generator = "system-uuid") 
    @GenericGenerator(name = "system-uuid", strategy = "uuid")
    @Column(length=32)
 @Id
 private String id;
 
 @Column(length=32)
 private String userName;
 
 @Column(length=32)
 private String age;
 
 public String getId() {
  return id;
 }
 public void setId(String id) {
  this.id = id;
 }
 public String getUserName() {
  return userName;
 }
 public void setUserName(String userName) {
  this.userName = userName;
 }
 public String getAge() {
  return age;
 }
 public void setAge(String age) {
  this.age = age;
 }

}
3.2 dao層結構如下：接口IUserDAO與實現類UserDAO，我們實現添刪改查，查詢包括一個User和所以User
com.zyh.web.controller.dao.IUserDAO

package com.zyh.web.controller.dao;

import java.util.List;

import com.zyh.web.controller.entity.User;

public interface IUserDAO {

 public void addUser(User user);
 
 public List<User> getAllUser();
 
 public User getUser(String id);
 
 public boolean delUser(String id);
 
 public boolean updateUser(User user);
}
實現類UserDAO:

package com.zyh.web.controller.dao;

import java.util.List;

import org.hibernate.Query;
import org.hibernate.SessionFactory;

import com.zyh.web.controller.entity.User;

public class UserDAO implements IUserDAO {

 private SessionFactory sessionFactory;
 public void setSessionFactory(SessionFactory sessionFactory) {
  this.sessionFactory = sessionFactory;
 }

 @Override
 public void addUser(User user) {
  // TODO Auto-generated method stub
  sessionFactory.getCurrentSession().save(user);
 }

 @Override
 public List<User> getAllUser() {
  // TODO Auto-generated method stub
  String hql = "from User";
  Query query =  sessionFactory.getCurrentSession().createQuery(hql);
  return query.list();
 }

 @Override
 public User getUser(String id) {
  // TODO Auto-generated method stub
  String hql = "from User u where u.id=?";
  Query query = sessionFactory.getCurrentSession().createQuery(hql);
  query.setString(0, id);
  return (User) query.uniqueResult();
 }

 @Override
 public boolean delUser(String id) {
  // TODO Auto-generated method stub
  String hql = "delete User u where u.id=?";
  Query query = sessionFactory.getCurrentSession().createQuery(hql);
  query.setString(0, id);
  return (query.executeUpdate()>0);
 }

 @Override
 public boolean updateUser(User user) {
  // TODO Auto-generated method stub
  String hql = "update User u set u.userName=?,u.age=? where u.id=?";
  Query query = sessionFactory.getCurrentSession().createQuery(hql);
  query.setString(0, user.getUserName());
  query.setString(1, user.getAge());
  query.setString(2, user.getId());
  return (query.executeUpdate()>0);
 }

}

3.3 service層結構如下：接口IUserManager與實現類UserManager，我們實現添刪改查，查詢包括一個User和所以User
com.zyh.web.controller.service.IUserManager

package com.zyh.web.controller.service;

import java.util.List;

import com.zyh.web.controller.entity.User;

public interface IUserManager {
 
 public void addUser(User user);
 
 public List<User> getAllUser();
 
 public boolean delUser(String id);
 
 public User getUser(String id);
 
 public boolean updateUser(User user);
}
實現類UserManager.java

package com.zyh.web.controller.service;

import java.util.List;

import com.zyh.web.controller.dao.IUserDAO;
import com.zyh.web.controller.entity.User;

public class UserManager implements IUserManager {
 
 private IUserDAO userDao;
 
 public void setUserDao(IUserDAO userDao) {
  this.userDao = userDao;
 }

 @Override
 public void addUser(User user) {
  // TODO Auto-generated method stub
  userDao.addUser(user);
 }

 @Override
 public List<User> getAllUser() {
  // TODO Auto-generated method stub
  return userDao.getAllUser();
 }

 @Override
 public boolean delUser(String id) {
  // TODO Auto-generated method stub
  return userDao.delUser(id);
 }

 @Override
 public User getUser(String id) {
  // TODO Auto-generated method stub
  return userDao.getUser(id);
 }

 @Override
 public boolean updateUser(User user) {
  // TODO Auto-generated method stub
  return userDao.updateUser(user);
 }

}

4.Control層結構如下：實現類UserController.java，代碼如下：

package com.zyh.web.controller;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import com.zyh.web.controller.entity.User;
import com.zyh.web.controller.service.IUserManager;

@Controller
@RequestMapping("/user")
public class UserController {
 @Resource(name="userManager")
 private IUserManager userManager;
 
 @RequestMapping("/toAddUser")
 public String toAddUser(){
  return "/addUser";
 }
 
 @RequestMapping("/addUser")
 public String addUser(User user){
  userManager.addUser(user);
  return "redirect:/user/getAllUser";
 }
 
 @RequestMapping("/getAllUser")
 public String getAllUser(HttpServletRequest request){
  List<User> user = userManager.getAllUser();
  request.setAttribute("user", user);
  return "/userManager";
 }
 
 @RequestMapping("/delUser")
 public void delUser(String id,HttpServletResponse response){
  String result = "{\"result\":\"error\"}";
  if(userManager.delUser(id)){
   result = "{\"result\":\"success\"}";
  }
  response.setContentType("application/json");
  PrintWriter pw;
  try {
   pw = response.getWriter();
   pw.write(result);
  } catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
 }
 
 @RequestMapping("/getUser")
 public String getUser(String id,HttpServletRequest request){
  User user = userManager.getUser(id);
  request.setAttribute("user", user);
  return "editUser";
 }
 
 @RequestMapping("/updateUser")
 public String updateUser(User user,HttpServletRequest request){
  if(userManager.updateUser(user)){
   userManager.getUser(user.getId());
   request.setAttribute("user", user);
   return "/editUser";
  }else{
   return "/error";
  }
 }
}

--

 

--

package com.zyh.web.controller;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import com.zyh.web.controller.entity.User;
import com.zyh.web.controller.service.IUserManager;

@Controller
@RequestMapping("/user")
public class UserController {
 @Resource(name="userManager")
 private IUserManager userManager;
 
 @RequestMapping("/toAddUser")
 public String toAddUser(){
  return "/addUser";
 }
 
 @RequestMapping("/addUser")
 public String addUser(User user){
  userManager.addUser(user);
  return "redirect:/user/getAllUser";
 }
 
 @RequestMapping("/getAllUser")
 public String getAllUser(HttpServletRequest request){
  List<User> user = userManager.getAllUser();
  request.setAttribute("user", user);
  return "/userManager";
 }
 
 @RequestMapping("/delUser")
 public void delUser(String id,HttpServletResponse response){
  String result = "{\"result\":\"error\"}";
  if(userManager.delUser(id)){
   result = "{\"result\":\"success\"}";
  }
  response.setContentType("application/json");
  PrintWriter pw;
  try {
   pw = response.getWriter();
   pw.write(result);
  } catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
 }
 
 @RequestMapping("/getUser")
 public String getUser(String id,HttpServletRequest request){
  User user = userManager.getUser(id);
  request.setAttribute("user", user);
  return "editUser";
 }
 
 @RequestMapping("/updateUser")
 public String updateUser(User user,HttpServletRequest request){
  if(userManager.updateUser(user)){
   userManager.getUser(user.getId());
   request.setAttribute("user", user);
   return "/editUser";
  }else{
   return "/error";
  }
 }
}

 

 

 

 

 

package com.zyh.web.controller.service;

import java.util.List;

import com.zyh.web.controller.dao.IUserDAO;
import com.zyh.web.controller.entity.User;

public class UserManager implements IUserManager {
 
 private IUserDAO userDao;
 
 public void setUserDao(IUserDAO userDao) {
  this.userDao = userDao;
 }

 @Override
 public void addUser(User user) {
  // TODO Auto-generated method stub
  userDao.addUser(user);
 }

 @Override
 public List<User> getAllUser() {
  // TODO Auto-generated method stub
  return userDao.getAllUser();
 }

 @Override
 public boolean delUser(String id) {
  // TODO Auto-generated method stub
  return userDao.delUser(id);
 }

 @Override
 public User getUser(String id) {
  // TODO Auto-generated method stub
  return userDao.getUser(id);
 }

 @Override
 public boolean updateUser(User user) {
  // TODO Auto-generated method stub
  return userDao.updateUser(user);
 }

}

--

package com.zyh.web.controller.service;

import java.util.List;

import com.zyh.web.controller.entity.User;

public interface IUserManager {
 
 public void addUser(User user);
 
 public List<User> getAllUser();
 
 public boolean delUser(String id);
 
 public User getUser(String id);
 
 public boolean updateUser(User user);
}

 

--

3.2 dao層結構如下：接口IUserDAO與實現類UserDAO，我們實現添刪改查，查詢包括一個User和所以User
com.zyh.web.controller.dao.IUserDAO

--

package com.zyh.web.controller.dao;

import java.util.List;

import org.hibernate.Query;
import org.hibernate.SessionFactory;

import com.zyh.web.controller.entity.User;

public class UserDAO implements IUserDAO {

 private SessionFactory sessionFactory;
 public void setSessionFactory(SessionFactory sessionFactory) {
  this.sessionFactory = sessionFactory;
 }

 @Override
 public void addUser(User user) {
  // TODO Auto-generated method stub
  sessionFactory.getCurrentSession().save(user);
 }

 @Override
 public List<User> getAllUser() {
  // TODO Auto-generated method stub
  String hql = "from User";
  Query query =  sessionFactory.getCurrentSession().createQuery(hql);
  return query.list();
 }

 @Override
 public User getUser(String id) {
  // TODO Auto-generated method stub
  String hql = "from User u where u.id=?";
  Query query = sessionFactory.getCurrentSession().createQuery(hql);
  query.setString(0, id);
  return (User) query.uniqueResult();
 }

 @Override
 public boolean delUser(String id) {
  // TODO Auto-generated method stub
  String hql = "delete User u where u.id=?";
  Query query = sessionFactory.getCurrentSession().createQuery(hql);
  query.setString(0, id);
  return (query.executeUpdate()>0);
 }

 @Override
 public boolean updateUser(User user) {
  // TODO Auto-generated method stub
  String hql = "update User u set u.userName=?,u.age=? where u.id=?";
  Query query = sessionFactory.getCurrentSession().createQuery(hql);
  query.setString(0, user.getUserName());
  query.setString(1, user.getAge());
  query.setString(2, user.getId());
  return (query.executeUpdate()>0);
 }

}

 

 

 

 

package com.zyh.web.controller.dao;

import java.util.List;

import com.zyh.web.controller.entity.User;

public interface IUserDAO {

 public void addUser(User user);
 
 public List<User> getAllUser();
 
 public User getUser(String id);
 
 public boolean delUser(String id);
 
 public boolean updateUser(User user);
}

--

package com.zyh.web.controller.entity;

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

import org.hibernate.annotations.GenericGenerator;

@Entity
@Table(name="T_USER")
public class User {

 @GeneratedValue(generator = "system-uuid") 
    @GenericGenerator(name = "system-uuid", strategy = "uuid")
    @Column(length=32)
 @Id
 private String id;
 
 @Column(length=32)
 private String userName;
 
 @Column(length=32)
 private String age;
 
 public String getId() {
  return id;
 }
 public void setId(String id) {
  this.id = id;
 }
 public String getUserName() {
  return userName;
 }
 public void setUserName(String userName) {
  this.userName = userName;
 }
 public String getAge() {
  return age;
 }
 public void setAge(String age) {
  this.age = age;
 }

}

--

 

 

 

 

 

 

 

/**
* @param 將字節數組轉換為ImageView可調用的Bitmap對象

 * @param bytes

 * @param opts

 * @return Bitmap

 */

 public static Bitmap getPicFromBytes(byte[] bytes, BitmapFactory.Options opts) {

     if (bytes != null)

        if (opts != null) 
             return BitmapFactory.decodeByteArray(bytes, 0, bytes.length,  opts); 
        else

            return BitmapFactory.decodeByteArray(bytes, 0, bytes.length); 
     return null;

}

這里我們主要來介紹一個BitmapFactory.Options這個類
    

BitmapFactory.Options這個類的詳解如下：

這個表格是從android sdk文檔里摘出來的，簡單看一下說明就明白是什么意思了。
下面我們回到我們的主題上來：怎樣獲取圖片的大小？
思路很簡單：
首先我們把這個圖片轉成Bitmap，然后再利用Bitmap的getWidth()和getHeight()方法就可以取到圖片的寬高了。
新問題又來了，在通過BitmapFactory.decodeFile(String path)方法將突破轉成Bitmap時，遇到大一些的圖片，我們經常會遇到OOM(Out Of Memory)的問題。怎么避免它呢？
這就用到了我們上面提到的BitmapFactory.Options這個類。

BitmapFactory.Options這個類，有一個字段叫做 inJustDecodeBounds 。SDK中對這個成員的說明是這樣的：
If set to true, the decoder will return null (no bitmap), but the out…
也就是說，如果我們把它設為true，那么BitmapFactory.decodeFile(String path, Options opt)并不會真的返回一個Bitmap給你，它僅僅會把它的寬，高取回來給你，這樣就不會占用太多的內存，也就不會那么頻繁的發生OOM了。
示例代碼如下：

這段代碼之后，options.outWidth 和 options.outHeight就是我們想要的寬和高了。

有了寬，高的信息，我們怎樣在圖片不變形的情況下獲取到圖片指定大小的縮略圖呢？
比如我們需要在圖片不變形的前提下得到寬度為200的縮略圖。
那么我們需要先計算一下縮放之后，圖片的高度是多少

這樣雖然我們可以得到我們期望大小的ImageView
但是在執行BitmapFactory.decodeFile(path, options);時，并沒有節約內存。要想節約內存，還需要用到BitmapFactory.Options這個類里的 inSampleSize 這個成員變量。
我們可以根據圖片實際的寬高和我們期望的寬高來計算得到這個值。

另外，為了節約內存我們還可以使用下面的幾個字段：

     public void doSome();
     public void exectueMethod();
}

第二部分：在一個類里面把它當做參數并用到該參數
如下所示：

public class MethodB {

     public double getTime(CallBackInterface callBack){
          long start = System.currentTimeMillis();
          callBack.exectueMethod();
          long end = System.currentTimeMillis();
          System.out.println("cost time="+(end-start));
          return end-start;
     }
}

第三部分：在另外一個類里面調用到getTime方法并實現回調函數
如下所示:

public class MethodA {

     public static void main(String[] args) {
          MethodB b = new MethodB();
          double d = b.getTime(new CallBackInterface() {
         @Override
           public void exectueMethod() {
                // TODO Auto-generated method stub
                new MethodA().testMethod();
           }
   
           @Override
           public void doSome() {
                // TODO Auto-generated method stub
           }
          });
          System.out.println("d="+d);
     }
     public void testMethod(){
          for(int i=0;i<10000;i++)
           System.out.print("");
     }
}

輸出結果：

cost time=31
d=31.0

理解“回調函數”

所謂回調，就是客戶程序CLIENT調用服務程序SERVER中的某個函數SA，然后SERVER又在某個時候反過來調用CLIENT中的某個函數CB，對于CLIENT來說，這個CB便叫做回調函數。例如Win32下的窗口過程函數就是一個典型的回調函數。 
一般說來，CLIENT不會自己調用CB，CLIENT提供CB的目的就是讓SERVER來調用它，而且是CLIENT不得不提供。由于SERVER并不知道CLIENT提供的CB叫甚名誰，所以SERVER會約定CB的接口規范（函數原型），然后由CLIENT提前通過SERVER的一個函數R告訴SERVER自己將要使用CB函數，這個過程稱為回調函數的注冊，R稱為注冊函數。Web SERVERerviCliente以及Java的RMI都用到回調機制，可以訪問遠程服務器程序。 

下面舉個通俗的例子： 
某天，我打電話向你請教問題，當然是個難題，:)，你一時想不出解決方法，我又不能拿著電話在那里傻等，于是我們約定：等你想出辦法后打手機通知我，這樣，我就掛掉電話辦其它事情去了。過了XX分鐘，我的手機響了，你興高采烈的說問題已經搞定，應該如此這般處理。故事到此結束。這個例子說明了“異步＋回調”的編程模式。其中，你后來打手機告訴我結果便是一個“回調”過程；我的手機號碼必須在以前告訴你，這便是注冊回調函數；我的手機號碼應該有效并且手機能夠接收到你的呼叫，這是回調函數必須符合接口規范。 
通過上面個人感覺到回調函數更多的應用就是結合異步。比如：ajax中jServer通過組件和服務器的異步通信。 

什么是回調函數 

精妙比喻:回調函數還真有點像您隨身帶的BP機：告訴別人號碼，在它有事情時Call您 
回調用于層間協作，上層將本層函數安裝在下層，這個函數就是回調，而下層在一定條件下觸發回調，例如作為一個驅動，是一個底層，他在收到一個數據時，除了完成本層的處理工作外，還將進行回調，將這個數據交給上層應用層來做進一步處理，這在分層的數據通信中很普遍。 
其實回調和API非常接近，他們的共性都是跨層調用的函數。但區別是API是低層提供給高層的調用，一般這個函數對高層都是已知的；而回調正好相反，他是高層提供給底層的調用，對于低層他是未知的，必須由高層進行安裝，這個安裝函數其實就是一個低層提供的API，安裝后低層不知道這個回調的名字，但它通過一個函數指針來保存這個回調，在需要調用時，只需引用這個函數指針和相關的參數指針。

其實：回調就是該函數寫在高層，低層通過一個函數指針保存這個函數，在某個事件的觸發下，低層通過該函數指針調用高層那個函數。

【參考】

http://blog.csdn.net/sweetwxh/article/details/2067139

http://liutiemeng.blog.51cto.com/120361/18874

http://kidult.iteye.com/blog/148982

public static void main(String[] args) {
  MethodB b = new MethodB();
  double d = b.getTime(new CallBackInterface() {
   
   @Override
   public void exectueMethod() {
    // TODO Auto-generated method stub
    new MethodA().testMethod();
   }
   
   @Override
   public void doSome() {
    // TODO Auto-generated method stub
    
   }
  });
  System.out.println("d="+d);
 }
 public void testMethod(){
  for(int i=0;i<10000;i++)
   System.out.print("");
 }

1. public class RunTimeTest {
2. /**
3. * @param args
4. */
5. public static void main(String[] args) {
6. Thread thread1 = new Thread() {
7. public void run() {
8. System.out.println("thread1...");
9. }
10. };
12. Thread thread2 = new Thread() {
13. public void run() {
14. System.out.println("thread2...");
15. }
16. };
18. Thread shutdownThread = new Thread() {
19. public void run() {
20. System.out.println("shutdownThread...");
21. }
22. };
24. Runtime.getRuntime().addShutdownHook(shutdownThread);
26. thread1.start();
27. thread2.start();
28. }
29. }

對Java程序來說，只要還有一個前臺線程在運行，這個進程就不會結束，如果一個進程中只有后臺線程在運行，這個進程就會結束。前臺線程是相對后臺線程而言的，前面所介紹的線程都是前臺線程。那么什么樣的線程是后臺線程呢？如果某個線程對象在啟動（調用start()方法）之前調用了setDaemon(true)方法，這個線程就變成了后臺線程。下面來看一下進程中只有后臺線程在運行的情況，如下所示：

范例：ThreadDaemon.java

01 public class ThreadDaemon

02 {

03 public static void main(String args[])

04 {

05 ThreadTest t = new ThreadTest() ;

06 Thread tt = new Thread(t) ;

07 tt.setDaemon(true) ; // 設置后臺運行

08 tt.start();

09 }

10 }

11

12 class ThreadTest implements Runnable

13 {

14 public void run()

15 {

16 while(true)

17 {

18 System.out.println(Thread.currentThread().getName()+"is running.");

19 }

20 }

21 }

從上面的程序和運行結果（圖9-4）上，可以看到：雖然創建了一個無限循環的線程，但因為它是后臺線程，整個進程在主線程結束時就隨之終止運行了。這驗證了

進程中只有后臺線程運行時，進程就會結束的說法。

1、PendingIntent作用

根據字面意思就知道是延遲的intent，主要用來在某個事件完成后執行特定的Action。PendingIntent包含了Intent及Context，所以就算Intent所屬程序結束，PendingIntent依然有效，可以在其他程序中使用。
常用在通知欄及短信發送系統中。

PendingIntent一般作為參數傳給某個實例，在該實例完成某個操作后自動執行PendingIntent上的Action，也可以通過PendingIntent的send函數手動執行，并可以在send函數中設置OnFinished表示send成功后執行的動作。

a. Intent是立即使用的，而PendingIntent可以等到事件發生后觸發，PendingIntent可以cancel
b. Intent在程序結束后即終止，而PendingIntent在程序結束后依然有效
c. PendingIntent自帶Context，而Intent需要在某個Context內運行
d. Intent在原task中運行，PendingIntent在新的task中運行

PhoneStateListener
1.對特定的電話狀態的監聽，包括服務的狀態、信號強度、消息等待指示（語音信箱）、通話轉移、呼叫狀態、設備單元位置、數據連接狀態、數據流量方向。一些電話信息受權限保護，應用程序不會收到受保護的信息的更新，除非在manifest文件中有適當的權限聲明。凡申請許可，有適當的LISTEN_標志。

2.對監聽的話做處理
Handler mHandler = new Handler() {
   public void handleMessage(Message msg) {
       switch (msg.what) {
           case LISTEN_SERVICE_STATE:/*Listen for changes to the network service state (cellular).對網絡服務狀態監聽*/
              PhoneStateListener.this.onServiceStateChanged((ServiceState)msg.obj);
              break;
           case LISTEN_SIGNAL_STRENGTH:/*Listen for changes to the network signal strength (cellular).對網絡信號強度變化監聽*/
              PhoneStateListener.this.onSignalStrengthChanged(msg.arg1);
              break;
           case LISTEN_MESSAGE_WAITING_INDICATOR:/*Listen for changes to the message-waiting indicator.對消息等待指示的變化監聽*/
              PhoneStateListener.this.onMessageWaitingIndicatorChanged(msg.arg1 != 0);
              break;
           case LISTEN_CALL_FORWARDING_INDICATOR:/*Listen for changes to the call-forwarding indicator.對通話轉移指示的變化監聽*/
              PhoneStateListener.this.onCallForwardingIndicatorChanged(msg.arg1 != 0);
              break;
           case LISTEN_CELL_LOCATION:/*Listen for changes to the device's cell location. Note that this will result in frequent callbacks to the listener.對設備單元位置的變化監聽，這會導致頻繁的監聽回調。*/
              PhoneStateListener.this.onCellLocationChanged((CellLocation)msg.obj);
              break;
           case LISTEN_CALL_STATE:/*Listen for changes to the device call state.對設備呼叫狀態的變化監聽。*/
              PhoneStateListener.this.onCallStateChanged(msg.arg1, (String)msg.obj);
              break;
           case LISTEN_DATA_CONNECTION_STATE:/*Listen for changes to the data connection state (cellular).對數據連接狀態的變化監聽。*/
              PhoneStateListener.this.onDataConnectionStateChanged(msg.arg1, msg.arg2);
              PhoneStateListener.this.onDataConnectionStateChanged(msg.arg1);
              break;
           case LISTEN_DATA_ACTIVITY:/*Listen for changes to the direction of data traffic on the data connection (cellular).對數據流量移動方向的變化監聽*/
            PhoneStateListener.this.onDataActivity(msg.arg1);
              break;
           case LISTEN_SIGNAL_STRENGTHS:/*Listen for changes to the network signal strengths (cellular).對網絡信號強度的變化監聽*/
              PhoneStateListener.this.onSignalStrengthsChanged((SignalStrength)msg.obj);
              break;
      }
   }
};

3.監聽變化后發送消息
IPhoneStateListener callback = new IPhoneStateListener.Stub() {
    public void onServiceStateChanged(ServiceState serviceState) {
        Message.obtain(mHandler, LISTEN_SERVICE_STATE, 0, 0, serviceState).sendToTarget();
    }
    public void onSignalStrengthChanged(int asu) {
        Message.obtain(mHandler, LISTEN_SIGNAL_STRENGTH, asu, 0, null).sendToTarget();
    }
    public void onMessageWaitingIndicatorChanged(boolean mwi) {
        Message.obtain(mHandler, LISTEN_MESSAGE_WAITING_INDICATOR, mwi ? 1 : 0, 0, null)
                .sendToTarget();
    }
    public void onCallForwardingIndicatorChanged(boolean cfi) {
        Message.obtain(mHandler, LISTEN_CALL_FORWARDING_INDICATOR, cfi ? 1 : 0, 0, null)
                .sendToTarget();
    }
    public void onCellLocationChanged(Bundle bundle) {
        CellLocation location = CellLocation.newFromBundle(bundle);
        Message.obtain(mHandler, LISTEN_CELL_LOCATION, 0, 0, location).sendToTarget();
    }
    public void onCallStateChanged(int state, String incomingNumber) {
        Message.obtain(mHandler, LISTEN_CALL_STATE, state, 0, incomingNumber).sendToTarget();
    }
    public void onDataConnectionStateChanged(int state, int networkType) {
        Message.obtain(mHandler, LISTEN_DATA_CONNECTION_STATE, state, networkType, null).
                sendToTarget();
    }
    public void onDataActivity(int direction) {
        Message.obtain(mHandler, LISTEN_DATA_ACTIVITY, direction, 0, null).sendToTarget();
    }
    public void onSignalStrengthsChanged(SignalStrength signalStrength) {
        Message.obtain(mHandler, LISTEN_SIGNAL_STRENGTHS, 0, 0, signalStrength).sendToTarget();
    }
};