CREATE TABLE Student( ID INT NOT NULL AUTO_INCREMENT, NAME VARCHAR(20) NOT NULL, AGE INT NOT NULL, PRIMARY KEY (ID) );
While proceeding with coding in Eclipse, required jar files needs to be added and JDBC latest libraries like mysql-connector-java.jar, org.springframework.jdbc.jar, org.springframework.transaction.jar in the project. Include DAO interface studentDAO, student table should be created in test database.
StudentDAO.java
package splessons; import java.util.List; import javax.sql.DataSource; public interface StudentDAO { /** * It is the method to initialize */ public void setDataSource(DataSource ds); /** * method used to create */ public void create(String name, Integer age); /** * method used to list down */ public Student getStudent(Integer id); /** * method used to list down * total files from the table. */ public List<Student> listStudents(); /** * method used to delete */ public void delete(Integer id); /** *method used to update * a file into the table. */ public void update(Integer id, Integer age); }
Student.java
package splessons; 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; } }
Here just created the data members such as age, name, id and also performed SET and GET operations to get the data.
StudentMapper.java
package splessons; 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; } }
RowMapper interface allows to map a row of the relations with the instance of user-defined class. It iterates the ResultSet internally and adds it into the collection. So we don’t need to write a lot of code to fetch the records as ResultSetExtractor. RowMapper saves a lot of code becuase it internally adds the data of ResultSet into the collection.
StudentJDBCTemplate.java
package splessons; import java.util.List; import javax.sql.DataSource; import org.springframework.jdbc.core.JdbcTemplate; public class StudentJDBCTemplate implements StudentDAO { private DataSource dataSource; private JdbcTemplate jdbcTemplateObject; public void setDataSource(DataSource dataSource) { this.dataSource = dataSource; this.jdbcTemplateObject = new JdbcTemplate(dataSource); } public void create(String name, Integer age) { String SQL = "insert into Student (name, age) values (?, ?)"; jdbcTemplateObject.update( SQL, name, age); System.out.println("Created Record Name = " + name + " Age = " + age); return; } public Student getStudent(Integer id) { String SQL = "select * from Student where id = ?"; Student student = jdbcTemplateObject.queryForObject(SQL, new Object[]{id}, new StudentMapper()); return student; } public List<Student> listStudents() { String SQL = "select * from Student"; List <Student> students = jdbcTemplateObject.query(SQL, new StudentMapper()); return students; } public void delete(Integer id){ String SQL = "delete from Student where id = ?"; jdbcTemplateObject.update(SQL, id); System.out.println("Deleted Record with ID = " + id ); return; } public void update(Integer id, Integer age){ String SQL = "update Student set age = ? where id = ?"; jdbcTemplateObject.update(SQL, age, id); System.out.println("Updated Record with ID = " + id ); return; } }
This is the implementation class file StudentJDBCTemplate.java for the defined DAO interface StudentDAO. Add Spring JDBC specific latest libraries mysql-connector-java.jar, org.springframework.jdbc.jar and org.springframework.transaction.jar in the project.
MainApp.java
package splessons; import java.util.List; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import com.tutorialspoint.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("sai", 22); studentJDBCTemplate.create("sravan", 23); studentJDBCTemplate.create("shiva", 25); 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("----Updating Record with ID = 2 -----" ); studentJDBCTemplate.update(2, 26); 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()); } }
The Application Context is spring’s more best in class holder. Like BeanFactory it can stack bean definitions, wire beans together and administer beans upon solicitation. Also it includes more enterprise-specific usefulness, for example, the capacity to determine literary messages from a properties document and the capacity to distribute application events to interested event listeners. This container is characterized by the org.springframework.context.ApplicationContext interface.
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://localhost:3306/TEST"/> <property name="username" value="root"/> <property name="password" value="password"/> </bean> <!-- Definition for studentJDBCTemplate bean --> <bean id="studentJDBCTemplate" class="splessons.StudentJDBCTemplate"> <property name="dataSource" ref="dataSource" /> </bean> </beans>
Make sure that data base connector needs to imported to the code. Spring JdbcTemplate is a powerful mechanism to connect to the database and execute SQL queries. It internally uses JDBC api, but eliminates a lot of problems of JDBC API.
Output
------Records Creation-------- Created Record Name = sai Age = 22 Created Record Name = sravan Age = 23 Created Record Name = shiva Age = 25 ------Listing Multiple Records-------- ID : 1, Name : sai, Age : 22 ID : 2, Name : sravan, Age : 23 ID : 3, Name : shiva, Age : 25 ----Updating Record with ID = 2 ----- Updated Record with ID = 2 ----Listing Record with ID = 2 ----- ID : 2, Name : sravan, Age : 26