How to close the ResultSet cursor automatically, after commit in JDBC?


ResultSet holdability determines whether the ResultSet objects (cursors) should be closed or held open when a transaction (that contains the said cursor/ ResultSet object) is committed using the commit() method of the Connection interface.

ResultSet interface provides two values to specify the holdability namely CLOSE_CURSORS_AT_COMMIT and HOLD_CURSORS_OVER_COMMIT

If the holdability of the ResultSet object is set to this value. Whenever you commit/save a transaction using the commit() method of the Connection interface, the ResultSet objects created in the current transaction (that are already opened) will be closed.

Therefore, if you need to close the ResultSet cursor after the commit automatically, set the ResultSet holdability to CLOSE_CURSORS_AT_COMMIT using the setHoldability() method of the Connection interface.

Let us create a table with name MyPlayers in MySQL database using CREATE statement as shown below −

CREATE TABLE MyPlayers(
   ID INT,
   First_Name VARCHAR(255),
   Last_Name VARCHAR(255),
   Date_Of_Birth date,
   Place_Of_Birth VARCHAR(255),
   Country VARCHAR(255),
   PRIMARY KEY (ID)
);

Now, we will insert 7 records in MyPlayers table using INSERT statements −

insert into MyPlayers values(1, 'Shikhar', 'Dhawan', DATE('1981-12-05'), 'Delhi', 'India');
insert into MyPlayers values(2, 'Jonathan', 'Trott', DATE('1981-04-22'), 'CapeTown', 'SouthAfrica');
insert into MyPlayers values(3, 'Kumara', 'Sangakkara', DATE('1977-10-27'), 'Matale', 'Srilanka');
insert into MyPlayers values(4, 'Virat', 'Kohli', DATE('1988-11-05'), 'Delhi', 'India');
insert into MyPlayers values(5, 'Rohit', 'Sharma', DATE('1987-04-30'), 'Nagpur', 'India');
insert into MyPlayers values(6, 'Ravindra', 'Jadeja', DATE('1988-12-06'), 'Nagpur', 'India');
insert into MyPlayers values(7, 'James', 'Anderson', DATE('1982-06-30'), 'Burnley', 'England');

Following JDBC program demonstrates how to close the ResultSet cursor immediately after commit.

Example

import java.sql.Connection;
import java.sql.Date;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class ResultSetHoldability_CloseCursorsAtCommit {
   public static void main(String args[]) throws SQLException {
      //Registering the Driver
      DriverManager.registerDriver(new com.mysql.jdbc.Driver());
      //Getting the connection
      String url = "jdbc:mysql://localhost/mydatabase";
      Connection con = DriverManager.getConnection(url, "root", "password");
      System.out.println("Connection established......");
      //Setting the auto commit false
      con.setAutoCommit(false);
      //Setting the holdability to CLOSE_CURSORS_AT_COMMIT
      con.setHoldability(ResultSet.CLOSE_CURSORS_AT_COMMIT);
      //Creating a Statement object
      Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
      //Retrieving the data
      ResultSet rs = stmt.executeQuery("select * from MyPlayers");
      System.out.println("Contents of the table");
      while(rs.next()) {
         System.out.print("ID: "+rs.getString("ID")+", ");
         System.out.print("First_Name: "+rs.getString("First_Name")+", ");
         System.out.print("Last_Name: "+rs.getString("Last_Name"));
         System.out.print("Date_Of_Birth: "+rs.getString("Date_Of_Birth")+", ");
         System.out.print("Place_Of_Birth: "+rs.getString("Place_Of_Birth"));
         System.out.print("Country: "+rs.getString("Country"));
         System.out.println("");
      }
      //Inserting a new row
      rs.moveToInsertRow();
      rs.updateInt(1, 8);
      rs.updateString(2, "Ishant");
      rs.updateString(3, "Sharma");
      rs.updateDate(4, new Date(904694400000L));
      rs.updateString(5, "Delhi");
      rs.updateString(6, "India");
      rs.insertRow();
      //Committing the transaction
      con.commit();
      boolean bool = rs.isClosed();
      if(bool) {
         System.out.println("ResultSet object is closed");
      } else {
         System.out.println("ResultSet object is open");
      }
   }
}

Output

Connection established......
Contents of the table
ID: 1, First_Name: Shikhar, Last_Name: DhawanDate_Of_Birth: 1981-12-05, Place_Of_Birth: DelhiCountry: India
ID: 2, First_Name: Jonathan, Last_Name: TrottDate_Of_Birth: 1981-04-22, Place_Of_Birth: CapeTownCountry: SouthAfrica
ID: 3, First_Name: Kumara, Last_Name: SangakkaraDate_Of_Birth: 1977-10-27, Place_Of_Birth: MataleCountry: Srilanka
ID: 4, First_Name: Virat, Last_Name: KohliDate_Of_Birth: 1988-11-05, Place_Of_Birth: MumbaiCountry: India
ID: 5, First_Name: Rohit, Last_Name: SharmaDate_Of_Birth: 1987-04-30, Place_Of_Birth: NagpurCountry: India
ID: 6, First_Name: Ravindra, Last_Name: JadejaDate_Of_Birth: 1988-12-06, Place_Of_Birth: NagpurCountry: India
ID: 7, First_Name: James, Last_Name: AndersonDate_Of_Birth: 1982-06-30, Place_Of_Birth: Burnley Country: England
ResultSet object is closed
raja
Published on 16-May-2019 12:02:08
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