### Question:
StatefulFilter implements ISOFilter, Configurable { protected void setSpace(Space space) { this.space = space; } StatefulFilter(); String getKeyPrefix(); void setKeyPrefix(String keyPrefix); void setConfiguration(Configuration cfg); void setSpace(String uri); ISOMsg filter(ISOChannel iSOChannel, ISOMsg m, LogEvent evt); boolean isVetoUnmatched(); void setVetoUnmatched(boolean vetoUnmatched); int getMatchDirection(); void setMatchDirection(int matchDirection); int getIgnoredField(int index); int[] getIgnoredFields(); void setIgnoredField(int index, int ignoredFields); void setIgnoredFields(int[] ignoredFields); int getSavedField(int index); int[] getSavedFields(); void setSavedField(int index, int savedFields); void setSavedFields(int[] savedFields); int getKey(int index); int[] getKey(); void setKey(int index, int key); void setKey(int[] key); long getTimeout(); void setTimeout(long timeout); boolean isOverwriteOriginalFields(); void setOverwriteOriginalFields(boolean overwriteOriginalFields);  }### Answer:
@Test public void testSetSpaceThrowsNullPointerException() throws Throwable { assertThrows(NullPointerException.class, () -> { StatefulFilter statefulFilter = new StatefulFilter(); statefulFilter.setSpace("Invalid space: "); }); }