Java Programcılarının yaptığı 10 temel hata

Java ile çalışırken yapılan 10 temel hatayı çözümü ile anlatmış bir kaynak. Aşağıdaki linkten ulaşabilirsiniz.  http://www.javacoffeebreak.com/articles/toptenerrors.html

JUnit - Basit bir örnek

http://www.ic.sunysb.edu/stu/yosong/cse219/junit.html import org.junit.*; public class ExampleTest {     /**      * methods annotated with @BeforeClass are      * called once before the test methods run      */     @BeforeClass     public static void setUpBeforeClass() {         ;     }         /**      * methods annotated with @AfterClass are      * called once after all test methods run      */     @AfterClass     public static void tearDownAfterClass() {         ;     }         /**      * methods annotated with @Before are      * called before every test case method      */     @Before     public void setUp() { ;     }     /**      * methods annotated with @After are      * called after every test case method      */     @After     public void tearDown() { ;     }         /**      * methods annotated with @Test are      * your actual Unit Test methods      * test using:      *    Assert.assertEquals      *    Assert.assertTrue      *    Assert.assertFalse      *    Assert.assertNotNull      *    Assert.assertNull      *    etc.      */     @Test     public void firstTest() { ;     }         @Test     public void secondTest() { ;     }     @Test(expected=Exception.class)     public void checkExceptionTest() { ;     } }

JDBC ile MySQL bağlantısı

package net.yusufsahin.pk1; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; public class MainProgram {         public static void main(String[] args) {                    try {                        Class.forName("com.mysql.jdbc.Driver");                        Connection con = DriverManager.getConnection("jdbc:mysql://localhost/sakila", "yourUserName", "yourPassword");                        PreparedStatement ps = con.prepareStatement("select customer_id,first_name,last_name from customer");                        ResultSet rs = ps.executeQuery();                                     while(rs.next()){                                    System.out.println(rs.getInt("customer_id")                                    +"-"+rs.getString("first_name")                                    +" "+rs.getString("last_name"));                                    }                    } catch (Exception {                               e.printStackTrace();                              }              } } Aşağıdaki gibi bir çıktı elde etmelisiniz.