import com.sun.tools.javac.api.ClientCodeWrapper.DiagnosticSourceUnwrapper; //导入依赖的package包/类
JCDiagnostic asJCDiagnostic(Diagnostic<? extends JavaFileObject> diagnostic) {
    if (diagnostic instanceof JCDiagnostic) {
        return (JCDiagnostic)diagnostic;
    } else if (diagnostic instanceof DiagnosticSourceUnwrapper) {
        return ((DiagnosticSourceUnwrapper)diagnostic).d;
    } else {
        throw new AssertionError("Cannot convert diagnostic to JCDiagnostic: " + diagnostic.getClass().getName());
    }
}
 

import com.sun.tools.javac.api.ClientCodeWrapper.DiagnosticSourceUnwrapper; //导入依赖的package包/类
public void report(Diagnostic message) {
    if (!(message instanceof DiagnosticSourceUnwrapper)) {
        throw new AssertionError("Wrapped diagnostic expected!");
    }
    String actual = message.toString();
    JCDiagnostic jd = (JCDiagnostic)((DiagnosticSourceUnwrapper)message).d;
    String expected = jd.toString();
    if (!actual.equals(expected)) {
        throw new AssertionError("expected = " + expected + "\nfound = " + actual);
    }
}