Debug Database connection : Connection « Database SQL JDBC « Java






Debug Database connection

    
import java.io.FileOutputStream;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class TestDebug_MySQL {
  public static Connection getConnection() throws Exception {
    String driver = "org.gjt.mm.mysql.Driver";
    String url = "jdbc:mysql://localhost/octopus";
    String username = "root";
    String password = "root";
    Class.forName(driver);
    return DriverManager.getConnection(url, username, password);
  }

  public static int countRows(Connection conn, String tableName) throws SQLException {
    Statement stmt = null;
    ResultSet rs = null;
    int rowCount = -1;
    try {
      stmt = conn.createStatement();
      rs = stmt.executeQuery("SELECT COUNT(*) FROM " + tableName);
      // get the number of rows from the result set
      rs.next();
      rowCount = rs.getInt(1);
    } finally {
      rs.close();
      stmt.close();
    }

    return rowCount;
  }

  public static void main(String[] args) {
    Connection conn = null;
    try {
      PrintWriter pw = new PrintWriter(new FileOutputStream("mysql_debug.txt"));
      DriverManager.setLogWriter(pw);
      conn = getConnection();
      String tableName = "myTable";
      System.out.println("tableName=" + tableName);
      System.out.println("conn=" + conn);
      System.out.println("rowCount=" + countRows(conn, tableName));
    } catch (Exception e) {
      e.printStackTrace();
      System.exit(1);
    } finally {
      try {
        conn.close();
      } catch (SQLException e) {
        e.printStackTrace();
      }
    }
  }
}
           
         
    
    
    
  








Related examples in the same category

1.Connect to more than one database
2.Verify database setup
3.Create Connection With Properties
4.Set save point
5.JDBC Simple Connection
6.Load some drivers
7.Encapsulate the Connection-related operations that every JDBC program seems to use
8.Test of loading a driver and connecting to a database
9.Load MySQL JDBC Driver
10.Oracle JDBC Driver load
11.Oracle JDBC Driver load test: NewInstance
12.Test Register Oracle JDBC Driver
13.Install Oracle Driver and Execute Resultset
14.Test Thin Net8 App
15.Specify a CharSet when connecting to a DBMS
16.Listing All Available Parameters for Creating a JDBC Connection
17.String java.sql.DriverPropertyInfo.name (Get name of property)
18.boolean java.sql.DriverPropertyInfo.required (Is property value required?)
19.String java.sql.DriverPropertyInfo.value (Get current value)
20.String java.sql.DriverPropertyInfo.description (Get description of property)
21.String[] java.sql.DriverPropertyInfo.choices (Get possible choices for property; if null, value can be any string)
22.Determining If a Database Supports Transactions
23.Committing and Rolling Back Updates to a Database
24.Disable auto commit mode in JDBC
25.Print warnings on a Connection to STDERR.
26.Print warnings on a Connection to a specified PrintWriter.
27.This program tests that the database and the JDBC driver are correctly configured.
28.Manage Db connections providing shortcuts for Statements, PreparedStatements and ResultSets.