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public class NewInstance {
  private static Throwable throwable;

  private NewInstance() throws Throwable {
    throw throwable;
  }

  public static synchronized void undeclaredThrow(Throwable throwable) {
    // These exceptions should not be passed
    if (throwable instanceof IllegalAccessException || 
        throwable instanceof InstantiationException) {
        throw new IllegalArgumentException(); // Unchecked, no declaration required
    }
       
    NewInstance.throwable = throwable;
    try {
      // next line throws the Throwable argument passed in above,
      // even though the throws clause of class.newInstance fails
      // to declare that this may happen
      NewInstance.class.newInstance();
    } catch (InstantiationException e) { /* unreachable */
    } catch (IllegalAccessException e) { /* unreachable */
    } finally { // Avoid memory leak 
      NewInstance.throwable = null; 
    }  
  }
}

public class UndeclaredException {
  public static void main(String[] args) {   // No declared checked exceptions
    NewInstance.undeclaredThrow(new Exception("Any checked exception"));
  }
}