JDBC原生工具类
获取数据库所有的表、表中的字段和注释<dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><scope>runtime</scope></dependency><depe
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获取数据库所有的表、表中的字段和注释
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
import lombok.Data;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;
import java.sql.*;
import java.util.ArrayList;
import java.util.List;
@Data
@Component
public class DatabaseUtil {
private final static Logger LOGGER = LoggerFactory.getLogger(DatabaseUtil.class);
private static final String DRIVER = "com.mysql.cj.jdbc.Driver";
private static String URL;
private static String USERNAME;
private static String PASSWORD;
/**
* 数据库操作
**/
private static final String SQL = "SELECT * FROM ";
//动态获取数据库yml配置
@Value("${spring.datasource.druid.url}")
private String url;
@Value("${spring.datasource.druid.username}")
private String username;
@Value("${spring.datasource.druid.password}")
private String password;
//静态方法获取数据
@PostConstruct
public void getMysqlData() {
//yml配置文件参数赋值给静态字段
URL = this.url;
USERNAME = this.username;
PASSWORD = this.password;
}
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;
//select * from + tableName
String tableSql = SQL + tableName;
//列名注释集合
List<String> columnComments = new ArrayList<>();
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;
}
}
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