### Question:
BooleanFunction implements Function { @Override public final double getDouble(Record rec) { return getBool(rec) ? 0 : 1; } BooleanFunction(int position); @Override final Long256 getLong256A(Record rec); @Override final Long256 getLong256B(Record rec); @Override final void getLong256(Record rec, CharSink sink); @Override final char getChar(Record rec); @Override final BinarySequence getBin(Record rec); @Override long getBinLen(Record rec); @Override final byte getByte(Record rec); @Override final long getDate(Record rec); @Override final double getDouble(Record rec); @Override final float getFloat(Record rec); @Override final int getInt(Record rec); @Override final long getLong(Record rec); @Override RecordMetadata getMetadata(); @Override int getPosition(); @Override final RecordCursorFactory getRecordCursorFactory(); @Override final short getShort(Record rec); @Override final CharSequence getStr(Record rec); @Override final void getStr(Record rec, CharSink sink); @Override final CharSequence getStrB(Record rec); @Override final int getStrLen(Record rec); @Override final CharSequence getSymbol(Record rec); @Override long getTimestamp(Record rec); @Override final int getType();  }### Answer:
@Test public void testGetDouble() { Assert.assertEquals(1.0, functionA.getDouble(null), 0.000001); Assert.assertEquals(0.0, functionB.getDouble(null), 0.000001); }