import java.sql.*;
import oracle.jdbc.*;
import oracle.sql.*;
import java.util.*;

public class ConnectionTest {

    public static void main(String [] args) {
        ConnectionTest cTest = new ConnectionTest();
        cTest.exec();
    }

    public void exec() {
        Connection conn = null;
        try {
            DriverManager.registerDriver(new oracle.jdbc.OracleDriver());
            conn = DriverManager.getConnection(
                "", 
                "", 
                "");
            DatabaseMetaData dbMeta = conn.getMetaData();
            int data = dbMeta.getDefaultTransactionIsolation();
            switch (data) {
        case Connection.TRANSACTION_NONE:
        case Connection.TRANSACTION_READ_COMMITTED:
        case Connection.TRANSACTION_READ_UNCOMMITTED:
        case Connection.TRANSACTION_REPEATABLE_READ:
        case Connection.TRANSACTION_SERIALIZABLE:
              System.out.println("default=" + data);
              break;
            default:
                break;
            }

            int [] aryIsolationLevel = new int [] {
        Connection.TRANSACTION_NONE,
        Connection.TRANSACTION_READ_COMMITTED,
        Connection.TRANSACTION_READ_UNCOMMITTED,
        Connection.TRANSACTION_REPEATABLE_READ,
        Connection.TRANSACTION_SERIALIZABLE
            };
 
            for (int i = 0; i < aryIsolationLevel.length; i++) {
                System.out.print(aryIsolationLevel[i]);
                boolean suppored =
                dbMeta.supportsTransactionIsolationLevel(aryIsolationLevel[i]);
   
                switch (aryIsolationLevel[i]) {
            case Connection.TRANSACTION_NONE:
                System.out.print("Connection.TRANSACTION_NONE:");
                    System.out.println(suppored ? "support" : "no");
                    break;
            case Connection.TRANSACTION_READ_COMMITTED:
                System.out.print("Connection.TRANSACTION_READ_COMMITTED");
                    System.out.println(suppored ? "support" : "no");
                    break;
            case Connection.TRANSACTION_READ_UNCOMMITTED:
                System.out.print("Connection.TRANSACTION_READ_UNCOMMITTED");
                    System.out.println(suppored ? "support" : "no");
                    break;
            case Connection.TRANSACTION_REPEATABLE_READ:
                System.out.print("Connection.TRANSACTION_REPEATABLE_READ");
                    System.out.println(suppored ? "support" : "no");
                    break;
                case Connection.TRANSACTION_SERIALIZABLE:
                System.out.print("Connection.TRANSACTION_SERIALIZABLE");
                    System.out.println(suppored ? "support" : "no");
                    break;
                default:
                    break;
                }
            } 
            // set isolation level
            conn.setTransactionIsolation(Connection.TRANSACTION_SERIALIZABLE);
            System.out.println("now:" +conn.getTransactionIsolation());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}