Java ResultSet afterLast() method with example


When we execute certain SQL queries (SELECT query in general) they return tabular data.

The java.sql.ResultSet interface represents such tabular data returned by the SQL statements.

i.e. the ResultSet object holds the tabular data returned by the methods that execute the statements which quires the database (executeQuery() method of the Statement interface in general).

The ResultSet object has a cursor/pointer which points to the current row. Initially this cursor is positioned before first row.

The afterLast() method of the ResultSet interface moves the pointer/cursor of the current ResultSet object to next position of the last row.

rs.afterLast();

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 establishes connection with the database, retrieves the contents of the table MyPlayers into a ResultSet object moves the position of the ResultSet pointer next to the last row using the afterLast() method and, prints the contents of the table form last to first.

Example

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class ResultSet_afterLast {
   public static void main(String args[]) throws SQLException {
      //Registering the Driver
      DriverManager.registerDriver(new com.mysql.jdbc.Driver());
      //Getting the connection
      String mysqlUrl = "jdbc:mysql://localhost/mydatabase";
      Connection con = DriverManager.getConnection(mysqlUrl, "root", "password");
      System.out.println("Connection established......");
      //Creating the Statement
      Statement stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);
      //Query to retrieve records
      String query = "Select * from MyPlayers";
      //Executing the query
      ResultSet rs = stmt.executeQuery(query);
      //Moving the cursor position to next to the last row
      rs.afterLast();
      System.out.println("Contents of the MyPlayers table from last to first: ");
      //Printing the contents of the ResultSet object from last to first
      while(rs.previous()) {
         System.out.print("ID: "+rs.getInt("ID")+", ");
         System.out.print("Name: "+rs.getString("First_Name")+", ");
         System.out.print("Age: "+rs.getString("Last_Name")+", ");
         System.out.print("Salary: "+rs.getDate("Date_Of_Birth")+", ");
         System.out.print("Country: "+rs.getString("Place_Of_Birth")+", ");
         System.out.print("Address: "+rs.getString("Country"));
         System.out.println();
      }
      System.out.println();
   }
}

Output

Connection established......
Contents of the MyPlayers table:
Contents of the MyPlayers table from last to first:
ID: 8, Name: Ryan, Age: McLaren, Salary: 1983-02-09, Country: Kumberly, Address: null
ID: 7, Name: James, Age: Anderson, Salary: 1982-06-30, Country: Burnley , Address: England
ID: 6, Name: Ravindra, Age: Jadeja, Salary: 1988-12-06, Country: Nagpur, Address: India
ID: 5, Name: Rohit, Age: Sharma, Salary: 1987-04-30, Country: Nagpur, Address: India
ID: 4, Name: Virat, Age: Kohli, Salary: 1988-11-05, Country: Mumbai, Address: India
ID: 3, Name: Kumara, Age: Sangakkara, Salary: 1977-10-27, Country: Matale, Address: Srilanka
ID: 2, Name: Jonathan, Age: Trott, Salary: 1981-04-22, Country: CapeTown, Address: SouthAfrica
ID: 1, Name: Shikhar, Age: Dhawan, Salary: 1981-12-05, Country: Delhi, Address: India
raja
Published on 13-May-2019 15:45:41
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