欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页

如何使用springtask定时去获取数据库的表,字段以及注释

程序员文章站 2024-03-21 21:52:28
...

如何使用springtask定时去获取数据库的表,字段以及注释

  1. 获取数据库中的表,字段以及注释工具类
package com.hw.util;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;

import java.sql.*;
import java.util.ArrayList;
import java.util.List;
import java.util.Timer;
import java.util.TimerTask;

/**
 * @author hw
 * @version 1.0
 * @date 2020/3/24 21:14
 */
@Component
public class DataBaseUtil {

    private final static Logger LOGGER = LoggerFactory.getLogger(DataBaseUtil.class);

    private static final String DRIVER = "com.mysql.jdbc.Driver";
    private static final String URL = "jdbc:mysql://localhost:3306/test_wechat?useUnicode=true&characterEncoding=utf8";
    private static final String USERNAME = "root";
    private static final String PASSWORD = "root";

    private static final String SQL = "SELECT * FROM ";// 数据库操作

    static {
        try {
            Class.forName(DRIVER);
        } catch (ClassNotFoundException e) {
            LOGGER.error("can not load jdbc driver", e);
        }
    }

    /**
     * 获取数据库连接
     *
     * @return
     */
    public static Connection getConnection() {
        Connection conn = null;
        try {
            conn = DriverManager.getConnection(URL, USERNAME, PASSWORD);
        } catch (SQLException e) {
            LOGGER.error("get connection failure", e);
        }
        return conn;
    }

    /**
     * 关闭数据库连接
     * @param conn
     */
    public static void closeConnection(Connection conn) {
        if(conn != null) {
            try {
                conn.close();
            } catch (SQLException e) {
                LOGGER.error("close connection failure", e);
            }
        }
    }

    /**
     * 获取数据库下的所有表名
     */
    public static List<String> getTableNames() {
        List<String> tableNames = new ArrayList<>();
        Connection conn = getConnection();
        ResultSet rs = null;
        try {
            //获取数据库的元数据
            DatabaseMetaData db = conn.getMetaData();
            //从元数据中获取到所有的表名
            rs = db.getTables(null, null, null, new String[] { "TABLE" });
            while(rs.next()) {
                tableNames.add(rs.getString(3));
            }
        } catch (SQLException e) {
            LOGGER.error("getTableNames failure", e);
        } finally {
            try {
                rs.close();
                closeConnection(conn);
            } catch (SQLException e) {
                LOGGER.error("close ResultSet failure", e);
            }
        }
        return tableNames;
    }

    /**
     * 获取表中所有字段名称
     * @param tableName 表名
     * @return
     */
    public static List<String> getColumnNames(String tableName) {
        List<String> columnNames = new ArrayList<>();
        //与数据库的连接
        Connection conn = getConnection();
        PreparedStatement pStemt = null;
        String tableSql = SQL + tableName;
        try {
            pStemt = conn.prepareStatement(tableSql);
            //结果集元数据
            ResultSetMetaData rsmd = pStemt.getMetaData();
            //表列数
            int size = rsmd.getColumnCount();
            for (int i = 0; i < size; i++) {
                columnNames.add(rsmd.getColumnName(i + 1));
            }
        } catch (SQLException e) {
            LOGGER.error("getColumnNames failure", e);
        } finally {
            if (pStemt != null) {
                try {
                    pStemt.close();
                    closeConnection(conn);
                } catch (SQLException e) {
                    LOGGER.error("getColumnNames close pstem and connection failure", e);
                }
            }
        }
        return columnNames;
    }

    /**
     * 获取表中所有字段类型
     * @param tableName
     * @return
     */
    public static List<String> getColumnTypes(String tableName) {
        List<String> columnTypes = new ArrayList<>();
        //与数据库的连接
        Connection conn = getConnection();
        PreparedStatement pStemt = null;
        String tableSql = SQL + tableName;
        try {
            pStemt = conn.prepareStatement(tableSql);
            //结果集元数据
            ResultSetMetaData rsmd = pStemt.getMetaData();
            //表列数
            int size = rsmd.getColumnCount();
            for (int i = 0; i < size; i++) {
                columnTypes.add(rsmd.getColumnTypeName(i + 1));
            }
        } catch (SQLException e) {
            LOGGER.error("getColumnTypes failure", e);
        } finally {
            if (pStemt != null) {
                try {
                    pStemt.close();
                    closeConnection(conn);
                } catch (SQLException e) {
                    LOGGER.error("getColumnTypes close pstem and connection failure", e);
                }
            }
        }
        return columnTypes;
    }

    /**
     * 获取表中字段的所有注释
     * @param tableName
     * @return
     */
    public static List<String> getColumnComments(String tableName) {
        List<String> columnTypes = new ArrayList<>();
        //与数据库的连接
        Connection conn = getConnection();
        PreparedStatement pStemt = null;
        String tableSql = SQL + tableName;
        List<String> columnComments = new ArrayList<>();//列名注释集合
        ResultSet rs = null;
        try {
            pStemt = conn.prepareStatement(tableSql);
            rs = pStemt.executeQuery("show full columns from " + tableName);
            while (rs.next()) {
                columnComments.add(rs.getString("Comment"));
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            if (rs != null) {
                try {
                    rs.close();
                    closeConnection(conn);
                } catch (SQLException e) {
                    LOGGER.error("getColumnComments close ResultSet and connection failure", e);
                }
            }
        }
        return columnComments;
    }

    public static void main(String[] args) {
        List<String> tableNames = getTableNames();
        System.out.println("tableNames:" + tableNames);
        for (String tableName : tableNames) {
            System.out.println("ColumnNames:" + getColumnNames(tableName));
//            System.out.println("ColumnTypes:" + getColumnTypes(tableName));
//            System.out.println("ColumnComments:" + getColumnComments(tableName));
        }
    }
}
  1. 启动类中添加可支持springtask注解
package com;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.scheduling.annotation.EnableScheduling;

/**
 * @author hw
 * @version 1.0
 * @date 2020/3/24 20:04
 */
@SpringBootApplication
@EnableScheduling
public class SpringTestProjectApplication {

    public static void main(String[] args) {
        System.out.println(SpringApplication.run(SpringTestProjectApplication.class,args));
    }
}
  1. 获取数据并返回
package com.hw;

import com.google.gson.JsonObject;
import com.hw.util.DataBaseUtil;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;

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

/**
 * @author hw
 * @version 1.0
 * @date 2020/3/24 19:57
 */
@Controller
public class FindAll {

    @RequestMapping("/findAll")
    @ResponseBody
    @Scheduled(cron = "0/1 * *  * * ? ")
    public List<String> TestDemo(){
        List<String> list = new ArrayList<>();
        List<String> tableNames = DataBaseUtil.getTableNames();
        for (String tableName : tableNames){
            List<String> columnNames = DataBaseUtil.getColumnNames(tableName);
            for (String columnName : columnNames){
                list.add(columnName);
            }
        }
        System.out.println(list);
        return list;
    }
}

相关标签: 学习