zseashell · November 24, 2015 08:17 · May 4, 2014 · Jul 25, 2013 · Jun 24, 2013 · Nov 19, 2012
diff --git a/MockPartialMethodTest.java b/MockPartialMethodTest.java
@@ -10,8 +10,9 @@
 import org.powermock.core.classloader.annotations.PrepareForTest;
 import org.powermock.modules.junit4.PowerMockRunner;
 
+// We prepare XxxServiceClass for test because it's final or we need to mock private or static methods
 @RunWith(PowerMockRunner.class)
-@PrepareForTest(XxxService.class)  // 必须添加此声明，否则会导致mock时实际调用方法
+@PrepareForTest(XxxService.class)  // spy是不需要声明 @PrepareForTest，但必须使用 doReturn("foo").when(spy).get(0);
 public class MockPartialMethodTest {
 
 	private XxxService service = new XxxService();

diff --git a/XxxUtil.java b/XxxUtil.java
@@ -1,4 +1,3 @@
-
 package demo.powermock;
 
 import java.io.File;

diff --git a/MockPartialMethodTest.java b/MockPartialMethodTest.java
@@ -22,6 +22,18 @@ public void mockPartialPrivateMethod() throws Exception {
 		service = PowerMockito.spy(service);
 		PowerMockito.doReturn(false).when(service, "isNeedHandle", anyInt()); // mock private method
 
+		/*
+		* spy must use doReturn()
+		*
+		List list = new LinkedList();
+		List spy = spy(list);
+		//Impossible: real method is called so spy.get(0) throws IndexOutOfBoundsException (the list is yet empty)
+		when(spy.get(0)).thenReturn("foo");
+		
+		//You have to use doReturn() for stubbing
+		doReturn("foo").when(spy).get(0);
+		*/
+
 		//action
 		boolean res = service.handle(2);
 

diff --git a/XxxUtil.java b/XxxUtil.java
@@ -1,3 +1,4 @@
+
 package demo.powermock;
 
 import java.io.File;

diff --git a/MockPartialMethodTest.java b/MockPartialMethodTest.java
@@ -1,26 +1,32 @@
 package demo.powermock;
 
+import static org.junit.Assert.assertFalse;
+import static org.mockito.Matchers.anyInt;
+import static org.mockito.Mockito.times;
+
 import org.junit.Test;
+import org.junit.runner.RunWith;
 import org.powermock.api.mockito.PowerMockito;
+import org.powermock.core.classloader.annotations.PrepareForTest;
+import org.powermock.modules.junit4.PowerMockRunner;
 
-import static org.mockito.Matchers.*;
-import static org.mockito.Mockito.*;
-import static org.junit.Assert.*;
-
+@RunWith(PowerMockRunner.class)
+@PrepareForTest(XxxService.class)  // 必须添加此声明，否则会导致mock时实际调用方法
 public class MockPartialMethodTest {
 
-	@Test
+	private XxxService service = new XxxService();
+
+	@Test 
 	public void mockPartialPrivateMethod() throws Exception {
 		//prepare
-		XxxService service = new XxxService();
 		service = PowerMockito.spy(service);
 		PowerMockito.doReturn(false).when(service, "isNeedHandle", anyInt()); // mock private method
 
 		//action
 		boolean res = service.handle(2);
 
 		//assert
-		assertFalse(res);
+		assertFalse(res); 
 		PowerMockito.verifyPrivate(service, times(1)).invoke("isNeedHandle", anyInt());
 	}
 

diff --git a/MockConstructionTest.java b/MockConstructionTest.java
@@ -0,0 +1,38 @@
+package demo.powermock;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.powermock.api.mockito.PowerMockito;
+import org.powermock.core.classloader.annotations.PrepareForTest;
+import org.powermock.modules.junit4.PowerMockRunner;
+
+import static org.junit.Assert.*;
+
+@RunWith(PowerMockRunner.class)
+@PrepareForTest(XxxService.class)  //注意：非 XxxUtil.class
+public class MockConstructionTest {
+
+	/*
+	 * 1.Use the @RunWith(PowerMockRunner.class) annotation at the class-level of the test case.
+	 * 2.Use the @PrepareForTest(ClassThatCreatesTheNewInstance.class) annotation at the class-level of the test case.
+	 * 3.PowerMockito.whenNew(MockNewClass.class)
+	 * 4.Note : withArguments(value), value必须与实际new时的参数类型相同
+	 */
+
+	@Test
+	public void mockConstruction() throws Exception {
+		//prepare
+		XxxService service = new XxxService();
+		XxxUtil util = new XxxUtil();
+		String name = "hello";
+		util.setName(name);
+		PowerMockito.whenNew(XxxUtil.class).withNoArguments().thenReturn(util);
+
+		//action
+		XxxUtil res = service.getUtil();
+
+		//assert
+		assertEquals(name, res.getName());
+	}
+
+}
diff --git a/MockFinalMethodOrClassTest.java b/MockFinalMethodOrClassTest.java
@@ -0,0 +1,9 @@
+package demo.powermock;
+
+/**
+ * 请大家自己测试
+ * @author bohan.sj
+ */
+public class MockFinalMethodOrClassTest {
+
+}
diff --git a/MockJavaCoreLibraryTest.java b/MockJavaCoreLibraryTest.java
@@ -0,0 +1,48 @@
+package demo.powermock;
+
+import static org.mockito.Matchers.anyLong;
+import static org.mockito.Mockito.*;
+
+import java.io.File;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.powermock.api.mockito.PowerMockito;
+import org.powermock.core.classloader.annotations.PrepareForTest;
+import org.powermock.modules.junit4.PowerMockRunner;
+
+@RunWith(PowerMockRunner.class)
+@PrepareForTest(XxxUtil.class)  // 注意：非 Thread.class 
+public class MockJavaCoreLibraryTest {
+
+	@Test
+	public void mockJavaCoreLibrary() throws Exception {
+		//prepare
+		PowerMockito.mockStatic(Thread.class);
+
+		//action
+		XxxUtil.sleep(1000);
+
+		//assert
+		PowerMockito.verifyStatic(times(1));
+		Thread.sleep(anyLong());
+	}
+
+	/**
+	 * 关键点：withArguments(value), value必须与实际new时的参数相同
+	 * @throws Exception
+	 */
+	@Test
+	public void readFile$mockNewFile() throws Exception {
+		//preapare
+		File file = mock(File.class);
+		PowerMockito.whenNew(File.class).withArguments(anyString()).thenReturn(file);
+
+		//action
+		XxxUtil.readFile(anyString());
+
+		//assert
+		verify(file, times(1)).getAbsolutePath();
+	}
+
+}
diff --git a/MockPartialMethodTest.java b/MockPartialMethodTest.java
@@ -0,0 +1,27 @@
+package demo.powermock;
+
+import org.junit.Test;
+import org.powermock.api.mockito.PowerMockito;
+
+import static org.mockito.Matchers.*;
+import static org.mockito.Mockito.*;
+import static org.junit.Assert.*;
+
+public class MockPartialMethodTest {
+
+	@Test
+	public void mockPartialPrivateMethod() throws Exception {
+		//prepare
+		XxxService service = new XxxService();
+		service = PowerMockito.spy(service);
+		PowerMockito.doReturn(false).when(service, "isNeedHandle", anyInt()); // mock private method
+
+		//action
+		boolean res = service.handle(2);
+
+		//assert
+		assertFalse(res);
+		PowerMockito.verifyPrivate(service, times(1)).invoke("isNeedHandle", anyInt());
+	}
+
+}
diff --git a/MockStaticMethodTest.java b/MockStaticMethodTest.java
@@ -0,0 +1,58 @@
+package demo.powermock;
+
+import static org.junit.Assert.assertFalse;
+import static org.mockito.Matchers.anyInt;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.when;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.powermock.api.mockito.PowerMockito;
+import org.powermock.core.classloader.annotations.PrepareForTest;
+import org.powermock.modules.junit4.PowerMockRunner;
+
+@RunWith(PowerMockRunner.class)
+@PrepareForTest(XxxUtil.class)
+public class MockStaticMethodTest {
+
+	@Test
+	public void mockStaticMethodAndVerifyStaticMethod() {
+		//prepare
+		XxxService service = new XxxService();
+		PowerMockito.mockStatic(XxxUtil.class);
+		when(XxxUtil.isSafe(anyInt())).thenReturn(false);
+
+		//action
+		boolean res = service.isAllowBuy(2);
+
+		//assert
+		assertFalse(res);
+
+		/*
+		 * 提示：静态方法verify有点别扭，如下是官方示例
+		 * 
+		// Different from Mockito, always use PowerMockito.verifyStatic() first
+        PowerMockito.verifyStatic(Mockito.times(2));
+        // Use EasyMock-like verification semantic per static method invocation
+        Static.firstStaticMethod(param);
+
+        // Remember to call verifyStatic() again
+        PowerMockito.verifyStatic(Mockito.never());
+        Static.secondStaticMethod();
+		 */
+		PowerMockito.verifyStatic(times(1));
+		XxxUtil.isSafe(anyInt());
+ 	}
+
+	@Test(expected=RuntimeException.class)
+	public void mockStaticMethodThrowException() {
+		//prepare
+		XxxService service = new XxxService();
+		PowerMockito.mockStatic(XxxUtil.class);
+		PowerMockito.doThrow(new RuntimeException()).when(XxxUtil.isSafe(anyInt()));
+
+		//action
+		service.isAllowBuy(2);
+	}
+
+}
diff --git a/PrivateFieldOrMethodTest.java b/PrivateFieldOrMethodTest.java
@@ -0,0 +1,64 @@
+package demo.powermock;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Matchers.anyInt;
+import static org.mockito.Mockito.times;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.powermock.api.mockito.PowerMockito;
+
+/**
+ * 注：当然可用反射实现同样目的，可认为powermock帮你提供工具类
+ * @author bohan.sj
+ */
+public class PrivateFieldOrMethodTest {
+
+	private XxxService target;
+
+	@Before
+	public void setUp() {
+		target = new XxxService();
+	}
+
+	@Test
+	public void modifyPrivateField() throws Exception {
+		//prepare
+		Field f = PowerMockito.field(XxxService.class, "threshold");
+		f.set(null, 10);
+
+		//action
+		int result = target.sum();
+
+		//assert
+		assertEquals(10, result);
+	}
+
+	@Test
+	public void testPrivateMethod() throws Exception {
+		//preapre
+		Method m = PowerMockito.method(XxxService.class, "isPositiveNumber", new Class[]{int.class});
+
+		//action
+		boolean res = (Boolean)m.invoke(target, 2);
+
+		//assert
+		assertTrue(res);
+	}
+
+	@Test
+	public void verifyPrivateMethodInvoke() throws Exception {
+		//prepare
+
+		//action
+		target.foreach(2);
+
+		//assert
+		PowerMockito.verifyPrivate(target, times(2)).invoke("isPositiveNumber", anyInt());
+	}
+
+}
diff --git a/XxxUtil.java b/XxxUtil.java
@@ -23,7 +23,7 @@ public void setName(String name) {
 
 	/*
 	 * 1. mock java core library
-	 * 	- 无结果返回，只能verify方法是否被调用
+	 *  - 无结果返回，只能verify方法是否被调用
 	 *  - 且是Java自身类
 	 */
 	public static void sleep(long time) throws Exception {

diff --git a/XxxService.java b/XxxService.java
@@ -0,0 +1,76 @@
+package demo.powermock;
+
+
+public class XxxService {
+
+	/* 
+	 * 1.修改私有域
+	 * 	- unit test 必须保证 '快'，需要修改private field
+	 */
+	private static int threshold = 1000000;
+	public int sum() {
+		int i=0;
+		while(i < threshold) {
+			i=i+1;
+		}
+		return i;
+	}
+
+	/*
+	 * 2.测试私有方法
+	 */
+	private boolean isPositiveNumber(int i) {
+		if(i > 0) {
+			return true;
+		} else {
+			return false;
+		}
+	}
+
+	/*
+	 * 3.无返回值，校验：对某方法调用次数
+	 */
+	public void foreach(int count) {
+		for(int i=0; i<count; i++) {
+			isPositiveNumber(i);
+		}
+	}
+
+	/*
+	 * 3.mock静态方法
+	 */
+	public boolean isAllowBuy(int i) {
+		//判断是否安全
+		if(XxxUtil.isSafe(i)) {
+			//判断是否超过支付能力
+			// ....
+		}
+		return false;
+	}
+
+	/*
+	 * 4.mock partial method
+	 *  - 需要mock isNeedHandle()，否则导致单元测试粒度太大
+	 */
+	public boolean handle(int i) {
+		if(isNeedHandle(i)) {
+			// ... logic handle
+			return true;
+		}
+		return false;
+	}
+	private boolean isNeedHandle(int i) {
+		//假设此方法逻辑，依赖外部服务、且逻辑较复杂
+		return true;
+	}
+
+
+	/*
+	 * 5.mock construction
+	 */
+	public XxxUtil getUtil() {
+		XxxUtil util = new XxxUtil();
+		return util;
+	}
+
+}
diff --git a/XxxUtil.java b/XxxUtil.java
@@ -0,0 +1,42 @@
+package demo.powermock;
+
+import java.io.File;
+
+
+public class XxxUtil {
+
+	public static boolean isSafe(int i) {
+		if(i > 0) {
+			return true;
+		} else {
+			return false;
+		}
+	}
+
+	private String name = "XxxUtil";
+	public String getName() {
+    	return name;
+    }
+	public void setName(String name) {
+    	this.name = name;
+    }
+
+	/*
+	 * 1. mock java core library
+	 * 	- 无结果返回，只能verify方法是否被调用
+	 *  - 且是Java自身类
+	 */
+	public static void sleep(long time) throws Exception {
+		Thread.sleep(time);
+	}
+
+	/*
+	 * 2. mock java core library
+	 *  - new instance
+	 */
+	public static void readFile(String filename) throws Exception {
+		File file = new File(filename);
+		System.out.println(file.getAbsolutePath());
+	}
+
+}