Is there a way to make a list from a MySQL table in Java?

MySQLMySQLi DatabaseJava

Yes, for this, use the concept of ArrayList in Java. The syntax is as follows −

ArrayList<ArrayList<yourDataType>> anyVariableName= new ArrayList<ArrayList<yourDataType>>();

Let us create a table −

mysql> create table demo10
−> (
−> id int not null auto_increment primary key,
−> name varchar(20)
−> );
Query OK, 0 rows affected (2.19 sec)

Insert some records into the table with the help of insert command −

mysql> insert into demo10(name) values('John');
Query OK, 1 row affected (0.23 sec)

mysql> insert into demo10(name) values('Bob');
Query OK, 1 row affected (0.12 sec)

mysql> insert into demo10(name) values('David');
Query OK, 1 row affected (0.13 sec)

Display records from the table using select statement −

mysql> select *from demo10;

This will produce the following output −

+----+-------+
| id | name  |
+----+-------+
| 1  | John  |
| 2  | Bob   |
| 3  | David |
+----+-------+
3 rows in set (0.00 sec)

Example

Following is the Java code −

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.util.ArrayList;
import com.mysql.jdbc.Statement;
public class ListInListDemo {
   public static void main(String[] args) {
      Connection con = null;
      Statement statement = null;
      try {
         ArrayList<ArrayList<String>> outer = new ArrayList<ArrayList<String>>();
         Class.forName("com.mysql.jdbc.Driver");
         con = DriverManager.getConnection("jdbc:mysql://localhost:3306/sampledatabase", "root",                "123456");
         statement = (Statement) con.createStatement();
         String sql;
         sql = "select *from demo10";
         ResultSet resultSet = statement.executeQuery(sql);
         while (resultSet.next()) {
            ArrayList<String> inner = new ArrayList<String>();
            inner.add(resultSet.getString("name"));
            outer.add(inner);
         }
         System.out.println("The name are as follows:");
         for (int i = 0; i < outer.size(); i++) {
            System.out.println(outer.get(i));
         }
      } catch (Exception e) {
         e.printStackTrace();
      }
   }
}

Output

This will produce the following output −

The name are as follows:
[John]
[Bob]
[David]

The snapshot is as follows −

raja
Published on 19-Nov-2020 15:33:43
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