If you need a data explorer of some sort inside your eclipse, you can look at the links provided above or more specifically the plugin's documentation.
OTOH, if you want to know how you connect to a mysql database using JDBC, the below code sample explains it.
Connection connection = null;
try {
//Loading the JDBC driver for MySql
Class.forName("com.mysql.jdbc.Driver");
//Getting a connection to the database. Change the URL parameters
connection = DriverManager.getConnection("jdbc:mysql://Server/Schema", "username", "password");
//Creating a statement object
Statement stmt = connection.createStatement();
//Executing the query and getting the result set
ResultSet rs = stmt.executeQuery("select * from item");
//Iterating the resultset and printing the 3rd column
while (rs.next()) {
System.out.println(rs.getString(3));
}
//close the resultset, statement and connection.
rs.close();
stmt.close();
connection.close();
} catch (SQLException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}