Question

为了模拟单元测试的数据，我使用的是Mockito。但我看到以下例外情况。我错过了任何设置吗？

此处使用的JVM是Java HotSpot（TM）64位服务器VM。 1.8

public class TestCreateObj{

  public void getMockData() {       
    TestObj deal = mock(TestObj.class);
    when(deal.getDescription()).thenReturn("HURRAH!!!");

    System.out.println(deal.getDescription());      
}

public static void main(String args[]) {
    new TestCreateObj().getMockData();
}

在运行时抛出此异常：

Caused by: java.lang.RuntimeException: Class file too large!
    at net.bytebuddy.jar.asm.ClassWriter.toByteArray(Unknown Source)
    at net.bytebuddy.dynamic.scaffold.TypeWriter$Default$ForCreation.create(TypeWriter.java:4108)
    at net.bytebuddy.dynamic.scaffold.TypeWriter$Default.make(TypeWriter.java:1612)
    at net.bytebuddy.dynamic.scaffold.subclass.SubclassDynamicTypeBuilder.make(SubclassDynamicTypeBuilder.java:174)
    at net.bytebuddy.dynamic.scaffold.subclass.SubclassDynamicTypeBuilder.make(SubclassDynamicTypeBuilder.java:155)
    at net.bytebuddy.dynamic.DynamicType$Builder$AbstractBase.make(DynamicType.java:2560)
    at net.bytebuddy.dynamic.DynamicType$Builder$AbstractBase$Delegator.make(DynamicType.java:2662)
    at org.mockito.internal.creation.bytebuddy.SubclassBytecodeGenerator.mockClass(SubclassBytecodeGenerator.java:94)
    at org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator$1.call(TypeCachingBytecodeGenerator.java:37)
    at org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator$1.call(TypeCachingBytecodeGenerator.java:34)
    at net.bytebuddy.TypeCache.findOrInsert(TypeCache.java:138)
    at net.bytebuddy.TypeCache$WithInlineExpunction.findOrInsert(TypeCache.java:346)
    at net.bytebuddy.TypeCache.findOrInsert(TypeCache.java:161)
    at net.bytebuddy.TypeCache$WithInlineExpunction.findOrInsert(TypeCache.java:355)
    at org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator.mockClass(TypeCachingBytecodeGenerator.java:32)
    at org.mockito.internal.creation.bytebuddy.SubclassByteBuddyMockMaker.createMockType(SubclassByteBuddyMockMaker.java:71)
    at org.mockito.internal.creation.bytebuddy.SubclassByteBuddyMockMaker.createMock(SubclassByteBuddyMockMaker.java:42)
    at org.mockito.internal.creation.bytebuddy.ByteBuddyMockMaker.createMock(ByteBuddyMockMaker.java:26)
    at org.mockito.internal.util.MockUtil.createMock(MockUtil.java:35)
    at org.mockito.internal.MockitoCore.mock(MockitoCore.java:65)
    at org.mockito.Mockito.mock(Mockito.java:1691)
    at org.mockito.Mockito.mock(Mockito.java:1604)

Answer 1

例外来自ASM，它抱怨Holger在评论中指出过大的常量池。这是将Mockito和PowerMock隐含的工具应用于已经很大的课程的结果。

Java类文件格式设置了一些限制，例如类声明的字段，方法或常量的数量。如果在非生成的Java类中越过此限制，则会产生类似的问题。

为了模拟一个类，Mockito要求Byte Buddy添加调度程序方法和合成方法来调用每个超级方法。这有效地使类的方法数量加倍，并且还增加了常量池。 PowerMock应用类似的东西。

如果你已经接近常数限制，那么这些添加最终会让你超越类文件所代表的边缘。它通常只发生在一个对象只包含几千个setter和getter的情况下，结果是你根本无法模拟这个对象，特别是在Mockito和PowerMock都处于活动状态时。

Mockito＆amp; PowerMock - 类大小限制

1 个答案: