解決:No qualifying bean of type [org.springframework.jdbc.core.JdbcTemplate] found for dependency

錯誤：

Description:

Field jdbcTemplate in com.gwd.dao.impl.IUserDaoImpl required a bean of type 'org.springframework.jdbc.core.JdbcTemplate' that could not be found.
- Bean method 'jdbcTemplate' not loaded because @ConditionalOnSingleCandidate (types: javax.sql.DataSource; SearchStrategy: all) did not find any beans

Action: 

Consider revisiting the conditions above or defining a bean of type 'org.springframework.jdbc.core.JdbcTemplate' in your configuration.

 

解決方案：

在運行類中加入以下代碼，DateSource這塊看本身的數據源，我這邊用的是阿里的druid

 

package com.gwd;
import javax.sql.DataSource;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.core.env.Environment;

import com.alibaba.druid.pool.DruidDataSource;

@SpringBootApplication
public class SpringBootTestApplication {
    public static void main(String[] args) {
        SpringApplication.run(SpringBootTestApplication.class, args);
    }

    @Autowired
    private Environment env;

    //destroy-method="close"的做用是當數據庫鏈接不使用的時候,就把該鏈接從新放到數據池中,方便下次使用調用.
    @Bean(destroyMethod =  "close")
    public DataSource dataSource() {
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setUrl(env.getProperty("spring.datasource.url"));
        dataSource.setUsername(env.getProperty("spring.datasource.username"));//用戶名
        dataSource.setPassword(env.getProperty("spring.datasource.password"));//密碼
        dataSource.setDriverClassName(env.getProperty("spring.datasource.driver-class-name"));
        dataSource.setInitialSize(2);//初始化時創建物理鏈接的個數
        dataSource.setMaxActive(20);//最大鏈接池數量
        dataSource.setMinIdle(0);//最小鏈接池數量
        dataSource.setMaxWait(60000);//獲取鏈接時最大等待時間，單位毫秒。
        dataSource.setValidationQuery("SELECT 1");//用來檢測鏈接是否有效的sql
        dataSource.setTestOnBorrow(false);//申請鏈接時執行validationQuery檢測鏈接是否有效
        dataSource.setTestWhileIdle(true);//建議配置爲true，不影響性能，而且保證安全性。
        dataSource.setPoolPreparedStatements(false);//是否緩存preparedStatement，也就是PSCache
        return dataSource;
    }
}