java - SQLException:当PowerMockito模拟静态DriverManager.class时，“未找到合适的驱动程序”

我正在尝试模拟Static DriverManager.class并获取mockConnection，但是真正的静态void方法却称为getConnection。

测试类别：

@RunWith(PowerMockRunner.class)
@PrepareForTest(DriverManager.class)
public class MyClassTest {

  @Before
  public void setUp() throws Exception {
    Connection connection = mock(Connection.class);
    Statement statement = mock(Statement.class);

    PowerMockito.mockStatic(DriverManager.class);
    PowerMockito.doReturn(connection).when(DriverManager.class, "getConnection", anyString(), anyString(), anyString());
  }

  @Test
  public void testMain() {
    // arrange
    String[] args = {"name", "password", "database"};
  }
}

Pom.xml

  <properties>
    <powermock.version>1.7.4</powermock.version>
  </properties>
  <dependencies>
    <!-- https://mvnrepository.com/artifact/junit/junit -->
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>

    <dependency>
      <groupId>org.powermock</groupId>
      <artifactId>powermock-module-junit4</artifactId>
      <version>${powermock.version}</version>
      <scope>test</scope>
    </dependency>
    <dependency>
      <groupId>org.powermock</groupId>
      <artifactId>powermock-api-mockito2</artifactId>
      <version>${powermock.version}</version>
      <scope>test</scope>
    </dependency>
  </dependencies>

尝试执行PowerMockito.doReturn（connection）.when（DriverManager.class，“ getConnection”，anyString（），anyString（），anyString（））时遇到的异常：

java.sql.SQLException: No suitable driver found for
at java.sql.DriverManager.getConnection(DriverManager.java:689)
at java.sql.DriverManager.getConnection(DriverManager.java:247)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.powermock.reflect.internal.WhiteboxImpl.performMethodInvocation(WhiteboxImpl.java:1846)
at org.powermock.reflect.internal.WhiteboxImpl.doInvokeMethod(WhiteboxImpl.java:810)
at org.powermock.reflect.internal.WhiteboxImpl.invokeMethod(WhiteboxImpl.java:790)
at org.powermock.reflect.Whitebox.invokeMethod(Whitebox.java:466)
at org.powermock.api.mockito.internal.expectation.PowerMockitoStubberImpl.when(PowerMockitoStubberImpl.java:110)
at vez.MyClassTest.setUp(MyClassTest.java:26)

我怎么了如何正确模拟DriverManager.class？
PS。当我查看org.powermock.api.mockito.internal.expectation.PowerMockitoStubberImpl.when（PowerMockitoStubberImpl.java:110）时，我看到它总是调用“ Whitebox.invokeMethod（classMock，methodToExpect，parameters）;”因此，我不了解它通常如何工作。

最佳答案

DriverManager类将尝试加载"jdbc.drivers"系统属性中引用的驱动程序类，作为其初始化的一部分。当加载DriverManager类时，即在调用getConnection()之类的任何方法之前，都会发生这种情况。因此，并不是您得到的异常是因为调用了真实的getConnection()。这是因为您没有在类路径中包含真实的驱动程序类，如pom所示，DriverManager可以在初始化期间加载。因此，在您的pom中包含一个驱动程序，然后尝试。

请在https://docs.oracle.com/javase/7/docs/api/java/sql/DriverManager.html处查看DriverManager类的源代码中的https://github.com/JetBrains/jdk8u_jdk/blob/master/src/share/classes/java/sql/DriverManager.java和static块。