40 JdbcTemplate batchUpdate() 实

在某些情况下，可能需要将一批记录插入到数据库中。如果你对每条记录调用一个插件的方法，SQL语句将被重复编译，造成系统缓慢进行。
在上述情况下，你可以使用 JdbcTemplate BATCHUPDATE()方法来执行批量插入操作。用这种方法，该语句只被编译一次，执行多次。

• 配置文件与上级篇中一直,只是路径不同

详见 JdbcTemplate 类的 BATCHUPDATE()示例。

package com.gp6.jdbc.template.batchUpdate.bean;

public class Customer {
    private int custId;
    private String name;
    private int age;
    
    public Customer(int custId, String name, int age) {
        this.custId = custId;
        this.name = name;
        this.age = age;
    }
    
    public Customer(){
        
    }
    
    
    public int getCustId() {
        return custId;
    }
    public void setCustId(int custId) {
        this.custId = custId;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
}

package com.gp6.jdbc.template.batchUpdate.dao;

import java.util.List;

import com.gp6.jdbc.template.batchUpdate.bean.Customer;

public interface CustomerDAO {
    public void insertBatch(final List<Customer> customers);
    public void insertBatchSQL(final String sql);
}

重点类

package com.gp6.jdbc.template.batchUpdate.dao.impl;


import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.List;

import org.springframework.jdbc.core.BatchPreparedStatementSetter;
import org.springframework.jdbc.core.support.JdbcDaoSupport;

import com.gp6.jdbc.template.batchUpdate.bean.Customer;
import com.gp6.jdbc.template.batchUpdate.dao.CustomerDAO;

public class CustomerDAOImpl extends JdbcDaoSupport implements CustomerDAO {
    
    public void insertBatch(final List<Customer> customers){
        String sql = "INSERT INTO CUSTOMER (CUST_ID, NAME, AGE) VALUES (?, ?, ?)";
                        
        getJdbcTemplate().batchUpdate(sql, new BatchPreparedStatementSetter() {
                    
            @Override
            public void setValues(PreparedStatement ps, int i) throws SQLException {
                Customer customer = customers.get(i);
                ps.setLong(1, customer.getCustId());
                ps.setString(2, customer.getName());
                ps.setInt(3, customer.getAge());
            }
                    
            @Override
            public int getBatchSize() {
                return customers.size();
            }
        });
    }
    
    public void insertBatchSQL(final String sql){
        getJdbcTemplate().batchUpdate(new String[]{sql});
    }
}

package com.gp6.jdbc.template.batchUpdate;

import java.util.ArrayList;
import java.util.List;

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

import com.gp6.jdbc.template.batchUpdate.bean.Customer;
import com.gp6.jdbc.template.batchUpdate.dao.CustomerDAO;

public class Test {
    public static void main( String[] args ) {
        ApplicationContext context = new ClassPathXmlApplicationContext("com/gp6/jdbc/template/batchUpdate/etc/applicationContext.xml");
         
        CustomerDAO customerDAO = (CustomerDAO) context.getBean("customerDAO");
        Customer customer1 = new Customer(1, "gp5",21);
        Customer customer3 = new Customer(2, "gp6",22);
        Customer customer2 = new Customer(3, "gp7",23);
  
        List<Customer>customers = new ArrayList<Customer>();
        customers.add(customer1);
        customers.add(customer2);
        customers.add(customer3);
        
        customerDAO.insertBatch(customers);

        String sql = "UPDATE CUSTOMER SET NAME ='BATCHUPDATE'";
        customerDAO.insertBatchSQL(sql);
    }
}