Spring JDBC - PreparedStatementSetter Interface

---

---

Overview

The org.springframework.jdbc.core.PreparedStatementSetter interface acts as a general callback interface used by the JdbcTemplate class. This interface sets values on a PreparedStatement provided by the JdbcTemplate class, for each of a number of updates in a batch using the same SQL.

Implementations are responsible for setting any necessary parameters. SQL with placeholders will already have been supplied. It's easier to use this interface than PreparedStatementCreator. The JdbcTemplate will create the PreparedStatement, with the callback only being responsible for setting parameter values.

Interface Declaration

Following is the declaration for org.springframework.jdbc.core.PreparedStatementSetter interface −

public interface PreparedStatementSetter

Usage

• Step 1 − Create a JdbcTemplate object using a configured datasource.

• Step 2 − Use JdbcTemplate object methods to make database operations while passing PreparedStatementSetter object to replace place holders in query.

Example

Following example will demonstrate how to read a query using JdbcTemplate class and PreparedStatementSetter interface. We'll read available record of a student in Student Table.

Syntax

final String SQL = "select * from Student where id = ? ";
List <Student> students = jdbcTemplateObject.query(
   SQL, new PreparedStatementSetter() {
   
   public void setValues(PreparedStatement preparedStatement) throws SQLException {
      preparedStatement.setInt(1, id);
   }
},
new StudentMapper());

Where,

• SQL − Select query to read students.

• jdbcTemplateObject − StudentJDBCTemplate object to read student object from database.

• PreparedStatementSetter − PreparedStatementSetter object to set parameters in query.

• StudentMapper − StudentMapper is a RowMapper object to map each fetched record to student object.

To understand the above-mentioned concepts related to Spring JDBC, let us write an example which will select a query. To write our example, let us have a working Eclipse IDE in place and use the following steps to create a Spring application.

StudentDAO.java

Following is the content of the Data Access Object interface file StudentDAO.java.

package com.tutorialspoint;

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 list down
    * a record from the Student table corresponding
    * to a passed student id.
   */
   public Student getStudent(Integer id);
}

Student.java

Following is the content of the Student.java file.

package com.tutorialspoint;

// Student POJO for Student Table
public class Student {
   private Integer age;
   private String name;
   private Integer id;

   // setter/getter methods
   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;
   }
}

StudentMapper.java

Following is the content of the StudentMapper.java file.

package com.tutorialspoint;

import java.sql.ResultSet;
import java.sql.SQLException;
import org.springframework.jdbc.core.RowMapper;

// Row Mapper Object to map Student table entry with Student Object
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;
   }
}

StudentJDBCTemplate.java

Following is the implementation class file StudentJDBCTemplate.java for the defined DAO interface StudentDAO.

package com.tutorialspoint;

import java.util.List;
import javax.sql.DataSource;
import org.springframework.jdbc.core.JdbcTemplate;

// DAO instance to persist Student values
public class StudentJDBCTemplate implements StudentDAO {
   private DataSource dataSource;
   private JdbcTemplate jdbcTemplateObject;

   // set the datasource and jdbctemplate   
   public void setDataSource(DataSource dataSource) {
      this.dataSource = dataSource;
      this.jdbcTemplateObject = new JdbcTemplate(dataSource);
   }
   // get all the students from the database
   public Student getStudent(final Integer id) {
      final String SQL = "select * from Student where id = ? ";
      List <Student> students = jdbcTemplateObject.query(
         SQL, new PreparedStatementSetter() {
            public void setValues(PreparedStatement preparedStatement) throws SQLException {
               preparedStatement.setInt(1, id);
            }
         },
         new StudentMapper()
      );
      return students.get(0);
   }
}

MainApp.java

Following is the content of the MainApp.java file.

package com.tutorialspoint;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class MainApp {
   public static void main(String[] args) {
      // Create the application context by reading Beans.xml   
      ApplicationContext context = new ClassPathXmlApplicationContext("Beans.xml");
      // Create the JDBCTemplate instance from spring context
      StudentJDBCTemplate studentJDBCTemplate = (StudentJDBCTemplate)context.getBean("studentJDBCTemplate");
      // get the student
      Student student = studentJDBCTemplate.getStudent(1);
      // print the student details
      System.out.print("ID : " + student.getId() );
      System.out.println(", Age : " + student.getAge()); 
   }
}

Beans.xml

Following is the configuration file 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.cj.jdbc.Driver"/>
      <property name = "url" value = "jdbc:mysql://localhost:3306/TEST"/>
      <property name = "username" value = "root"/>
      <property name = "password" value = "admin"/>
   </bean>

   <!-- Definition for studentJDBCTemplate bean -->
   <bean id = "studentJDBCTemplate" 
      class = "com.tutorialspoint.StudentJDBCTemplate">
      <property name = "dataSource" ref = "dataSource" />    
   </bean>      
</beans>

Output

Once you are done creating the source and bean configuration files, let us run the application. If everything is fine with your application, it will print the following message.

ID : 1, Age : 17