Java如何使用DatabaseMetaData获取表列名称？
在此示例中，我们使用DatabaseMetaData检索表的列名。可以通过调用来获取元数据信息connection.getMetaData()。接下来，我们可以ResultSet通过调用获取对象metadata.getColumns(Stringcatalog,StringschemaPattern,StringtableNamePattern,StringcolumnNamePattern)。
从这个结果集COLUMN_NAME，TYPE_NAME，COLUMN_SIZE和其他信息可以被读取。
package org.nhooo.example.jdbc;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
public class DbMetadataExample {
private static final String URL = "jdbc:mysql://localhost/nhooo";
private static final String USERNAME = "root";
private static final String PASSWORD = "";
public static void main(String[] args) {
try (Connection connection =
DriverManager.getConnection(URL, USERNAME, PASSWORD)) {
DatabaseMetaData metadata = connection.getMetaData();
ResultSet resultSet =
metadata.getColumns(null, null, "books", null);
while (resultSet.next()) {
String name = resultSet.getString("COLUMN_NAME");
String type = resultSet.getString("TYPE_NAME");
int size = resultSet.getInt("COLUMN_SIZE");
System.out.println("Column name: [" + name + "]; " +
"type: [" + type + "]; size: [" + size + "]");
}
} catch (SQLException e) {
e.printStackTrace();
}
}
}下books表描述了位信息：
Column name: [isbn]; type: [VARCHAR]; size: [50] Column name: [title]; type: [VARCHAR]; size: [100] Column name: [published_year]; type: [INT]; size: [10] Column name: [price]; type: [DECIMAL]; size: [10]
Maven依赖
<!-- https://search.maven.org/remotecontent?filepath=mysql/mysql-connector-java/8.0.17/mysql-connector-java-8.0.17.jar -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.17</version>
</dependency>