### Question:
MemoryGroupByData extends BaseStepData implements StepDataInterface { public HashEntry getHashEntry( Object[] groupData ) { return new HashEntry( groupData ); } MemoryGroupByData(); HashEntry getHashEntry( Object[] groupData ); void clear(); public HashMap<HashEntry, Aggregate> map; public RowMetaInterface aggMeta; public RowMetaInterface groupMeta; public RowMetaInterface entryMeta; public RowMetaInterface groupAggMeta; public int[] groupnrs; public int[] subjectnrs; public boolean firstRead; public Object[] groupResult; public boolean hasOutput; public RowMetaInterface inputRowMeta; public RowMetaInterface outputRowMeta; public ValueMetaInterface valueMetaInteger; public ValueMetaInterface valueMetaNumber; public boolean newBatch; }### Answer:
@Test public void hashEntryTest() { HashMap<MemoryGroupByData.HashEntry, String> map = new HashMap<>(); byte[] byteValue1 = "key".getBytes(); Object[] groupData1 = new Object[1]; groupData1[0] = byteValue1; MemoryGroupByData.HashEntry hashEntry1 = data.getHashEntry( groupData1 ); map.put( hashEntry1, "value" ); byte[] byteValue2 = "key".getBytes(); Object[] groupData2 = new Object[1]; groupData2[0] = byteValue2; MemoryGroupByData.HashEntry hashEntry2 = data.getHashEntry( groupData2 ); String value = map.get( hashEntry2 ); assertEquals( "value", value ); }