Junit 4 斷言方法允許檢查測試方法的期望結(jié)果值和真實(shí)返回值。Junit的org.junit.Assert類提供了各種斷言方法來寫junit測試。這些方法被用來檢查方法的真實(shí)結(jié)果值和期望值。下列一些有用的斷言方法列表：

 Junit 4斷言方法樣例

AssertionsTest.java junit測試用例，顯示各種斷言方法：

import static org.junit.Assert.*;
import java.util.ArrayList;
import java.util.List;
import org.junit.Test;
/**
* @author javatutorials.co.in
*/
public class AssertionsTest {
@Test
public void testAssertNull() {
String str = null;
assertNull(str);
}
@Test
public void testAssertNotNull() {
String str = "hello Java!!";
assertNotNull(str);
}
@Test
public void testAssertEqualsLong() {
long long1 = 2;
long long2 = 2;
assertEquals(long1, long2);
}
@Test
public void testAssertEqualsDouble() {
// test case is successfull as double1 and double 2
// differ by 0.001 which is less than our specified delta
double double1 = 1.236;
double double2 = 1.237;
double delta = 0.002;
assertEquals(double1, double2, delta);
}
@Test
public void testAssertTrue() {
List<String> list = new ArrayList<String>();
assertTrue(list.isEmpty());
}
@Test
public void testAssertFalse() {
List<String> list = new ArrayList<String>();
list.add("hello");
assertFalse(list.isEmpty());
}
@Test
public void testAssertSame() {
String str1 = "hello world!!";
String str2 = "hello world!!";
assertSame(str2, str1);
}
@Test
public void testAssertNotSame() {
String str1 = "hello world!!";
String str3 = "hello Java!!";
assertNotSame(str1, str3);
}
}

樣例輸出

在eclipse Junit 窗口的輸出如下：