Spring SQL存储过程

  • Spring SQL存储过程示例

    SimpleJdbcCall类可用于调用与IN和OUT参数的存储过程。在与RDBMS(如Apache Derby,DB2,MySQL,Microsoft SQL Server,Oracle和Sybase)一起使用时,可以使用此方法。为了理解这种方法,让我们采用我们的Student表,该表可以在MySQL test数据库中使用以下DDL创建
    CREATE TABLE Student(
       ID   INT NOT NULL AUTO_INCREMENT,
       NAME VARCHAR(20) NOT NULL,
       AGE  INT NOT NULL,
       PRIMARY KEY (ID)
    );
    接下来,考虑以下MySQL存储过程,该过程使用学生ID,并使用OUT参数返回相应学生的姓名和年龄。因此,让我们使用MySQL命令提示符在您的test数据库中创建此存储过程-
    DELIMITER $
    
    DROP PROCEDURE IF EXISTS `test`.`getRecord` $
    CREATE PROCEDURE `test`.`getRecord` (
    IN in_id INTEGER,
    OUT out_name VARCHAR(20),
    OUT out_age  INTEGER)
    BEGIN
       SELECT name, age
       INTO out_name, out_age
       FROM Student where id = in_id;
    END $
    
    DELIMITER ;
    现在让我们编写我们的Spring JDBC应用程序,它将在Student表上实现一个简单的Create和Read操作。让我们拥有一个运行良好的Eclipse IDE,并采取以下步骤来创建一个Spring应用程序:
    1. 创建一个名称为SpringExample的项目,并在创建的项目的src文件夹下创建一个包com.jc2182。
    2. 使用“添加外部JAR”选项添加所需的Spring库,如“Spring Hello World示例”一章中所述。
    3. 在项目中添加特定于Spring JDBC的最新库mysql-connector-java.jar,org.springframework.jdbc.jar和 org.springframework.transaction.jar。如果尚未下载所需的库,则可以下载它们。
    4. 创建DAO界面StudentDAO并列出所有必需的方法。尽管这不是必需的,并且您可以直接编写StudentJDBCTemplate类,但是作为一个好习惯,让我们开始吧。
    5. 在com.jc2182包下创建其他所需的Java类Student,StudentMapper,StudentJDBCTemplate和MainApp。
    6. 确保您已经在test数据库中创建了Student表。另外,请确保您的MySQL服务器运行正常,并使用用户名和密码对数据库具有读/写访问权限。
    7. 在src文件夹下创建Beans配置文件Beans.xml。
    8. 最后一步是创建所有Java文件和Bean配置文件的内容,然后按以下说明运行应用程序。
    以下是数据访问对象接口文件StudentDAO.java的内容 -
    package com.jc2182;
    
    import java.util.List;
    import javax.sql.DataSource;
    
    public interface StudentDAO {
       /** 
          * This is the method to be used to initialize
          * database resources ie. connection.
       */
       public void setDataSource(DataSource ds);
       
       /** 
          * This is the method to be used to create
          * a record in the Student table.
       */
       public void create(String name, Integer age);
      
       /** 
          * This is the method to be used to list down
          * a record from the Student table corresponding
          * to a passed student id.
       */
       public Student getStudent(Integer id);
       
       /** 
          * This is the method to be used to list down
          * all the records from the Student table.
       */
       public List<Student> listStudents();
    }
    以下是Student.java文件的内容的内容 -
    package com.jc2182;
    
    public class Student {
       private Integer age;
       private String name;
       private Integer id;
    
       public void setAge(Integer age) {
          this.age = age;
       }
       public Integer getAge() {
          return age;
       }
       public void setName(String name) {
          this.name = name;
       }
       public String getName() {
          return name;
       }
       public void setId(Integer id) {
          this.id = id;
       }
       public Integer getId() {
          return id;
       }
    }
    以下是StudentMapper.java文件的内容
    package com.jc2182;
    
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import org.springframework.jdbc.core.RowMapper;
    
    public class StudentMapper implements RowMapper<Student> {
       public Student mapRow(ResultSet rs, int rowNum) throws SQLException {
          Student student = new Student();
          student.setId(rs.getInt("id"));
          student.setName(rs.getString("name"));
          student.setAge(rs.getInt("age"));
          return student;
       }
    }
    以下是已定义的DAO接口StudentDAO的实现类文件StudentJDBCTemplate.java。
    package com.jc2182;
    
    import java.util.Map;
    import java.util.List;
    
    import javax.sql.DataSource;
    import org.springframework.jdbc.core.JdbcTemplate;
    import org.springframework.jdbc.core.namedparam.MapSqlParameterSource;
    import org.springframework.jdbc.core.namedparam.SqlParameterSource;
    import org.springframework.jdbc.core.simple.SimpleJdbcCall;
    
    public class StudentJDBCTemplate implements StudentDAO {
       private DataSource dataSource;
       private SimpleJdbcCall jdbcCall;
       private JdbcTemplate jdbcTemplateObject;
    
       public void setDataSource(DataSource dataSource) {
          this.dataSource = dataSource;
          this.jdbcCall =  new SimpleJdbcCall(dataSource).withProcedureName("getRecord");
          this.jdbcTemplateObject = new JdbcTemplate(dataSource);
       }
       public void create(String name, Integer age) {
          //JdbcTemplate jdbcTemplateObject = new JdbcTemplate(dataSource);
          String SQL = "insert into Student (name, age) values (?, ?)";
    
          this.jdbcTemplateObject.update( SQL, name, age);
          System.out.println("Created Record Name = " + name + " Age = " + age);
          return;
       }
       public Student getStudent(Integer id) {
          SqlParameterSource in = new MapSqlParameterSource().addValue("in_id", id);
          Map<String, Object> out = jdbcCall.execute(in);
    
          Student student = new Student();
          student.setId(id);
          student.setName((String) out.get("out_name"));
          student.setAge((Integer) out.get("out_age"));
          return student;
       }
       public List<Student> listStudents() {
          String SQL = "select * from Student";
          List <Student> students = this.jdbcTemplateObject.query(SQL, new StudentMapper());
          return students;
       }
    }
    关于上述程序的几句话:您为执行调用而编写的代码涉及创建一个包含IN参数的SqlParameterSource。将输入值提供的名称与存储过程中声明的参数名称的名称进行匹配很重要。的执行方法将IN参数,并返回包含任何出由名称键控参数的映射作为在存储过程中指定。现在,让我们移动主应用程序文件MainApp.java,如下所示-
    以下是MainApp.java文件的内容
    package com.jc2182;
    
    import java.util.List;
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.support.ClassPathXmlApplicationContext;
    import com.jc2182.StudentJDBCTemplate;
    
    public class MainApp {
       public static void main(String[] args) {
          ApplicationContext context = new ClassPathXmlApplicationContext("Beans.xml");
          StudentJDBCTemplate studentJDBCTemplate = 
             (StudentJDBCTemplate)context.getBean("studentJDBCTemplate");
          
          System.out.println("------Records Creation--------" );
          studentJDBCTemplate.create("Zara", 11);
          studentJDBCTemplate.create("Nuha", 2);
          studentJDBCTemplate.create("Ayan", 15);
    
          System.out.println("------Listing Multiple Records--------" );
          List<Student> students = studentJDBCTemplate.listStudents();
          
          for (Student record : students) {
             System.out.print("ID : " + record.getId() );
             System.out.print(", Name : " + record.getName() );
             System.out.println(", Age : " + record.getAge());
          }
          System.out.println("----Listing Record with ID = 2 -----" );
          Student student = studentJDBCTemplate.getStudent(2);
          System.out.print("ID : " + student.getId() );
          System.out.print(", Name : " + student.getName() );
          System.out.println(", Age : " + student.getAge());
       }
    }
    以下是配置文件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" 
       xsi:schemaLocation = "http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans-3.0.xsd ">
    
       <!-- Initialization for data source -->
       <bean id = "dataSource" 
          class = "org.springframework.jdbc.datasource.DriverManagerDataSource">
          <property name = "driverClassName" value = "com.mysql.jdbc.Driver"/>
          <property name = "url" value = "jdbc:mysql://192.168.61.125:3306/test"/>
          <property name = "username" value = "root"/>
          <property name = "password" value = "123456"/>
       </bean>
    
       <!-- Definition for studentJDBCTemplate bean -->
       <bean id = "studentJDBCTemplate" 
          class = "com.jc2182.StudentJDBCTemplate">
          <property name = "dataSource" ref = "dataSource" />    
       </bean>
          
    </beans>
    
    完成创建源和Bean配置文件后,让我们运行该应用程序。如果您的应用程序一切正常,它将显示以下消息:
    ------Records Creation--------
    Created Record Name = Zara Age = 11
    Created Record Name = Nuha Age = 2
    Created Record Name = Ayan Age = 15
    ------Listing Multiple Records--------
    ID : 1, Name : Zara, Age : 11
    ID : 2, Name : Nuha, Age : 2
    ID : 3, Name : Ayan, Age : 15
    ----Listing Record with ID = 2 -----
    ID : 2, Name : Nuha, Age : 2