Java Connect to postgresql Database Using JDBC Example
- 2021-06-28 09:09:06
- OfStack
This article provides an example of how Java uses JDBC to connect to an postgresql database.Share it for your reference, as follows:
package tool;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class PsqlConnectionTool {
private String url = "jdbc:postgresql://xxx.xxx.xxx.xxx:5432/testdb";
private String username = "postgres";
private String password = "postgres";
private Connection connection = null;
public Connection getConn() {
try {
Class.forName("org.postgresql.Driver").newInstance();
connection = DriverManager.getConnection(url, username, password);
} catch (InstantiationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return connection;
}
public ResultSet query(Connection conn, String sql) {
PreparedStatement pStatement = null;
ResultSet rs = null;
try {
pStatement = conn.prepareStatement(sql);
rs = pStatement.executeQuery();
} catch (SQLException e) {
e.printStackTrace();
}
return rs;
}
public boolean queryUpdate(Connection conn, String sql) {
PreparedStatement pStatement = null;
int rs = 0;
try {
pStatement = conn.prepareStatement(sql);
rs = pStatement.executeUpdate();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
if (rs > 0) {
return true;
}
return false;
}
public static void main(String[] args) throws SQLException {
PsqlConnectionTool pgtool = new PsqlConnectionTool();
Connection myconn = pgtool.getConn();
pgtool.queryUpdate(myconn, "insert into test values (1,'smoon','man')");
ResultSet rs = pgtool.query(myconn, "select * from test");
while(rs.next()){
int id = rs.getInt("id");
String name = rs.getString("name");
String gender = rs.getString("gender");
System.out.println("id:"+id+" Full name: "+name+" Gender: "+gender);
myconn.close();
}
}
}
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I hope that the description in this paper will be helpful to everyone's java program design.