| public static LongToPrefixCoded ( long val, int shift, BytesRef bytes ) : void | ||
| val | long | the numeric value |
| shift | int | how many bits to strip from the right |
| bytes | BytesRef | will contain the encoded value |
| return | void | |
public virtual void TestLongSpecialValues()
{
long[] vals = new long[] { System.Int64.MinValue, System.Int64.MinValue + 1, System.Int64.MinValue + 2, -5003400000000L, -4000L, -3000L, -2000L, -1000L, -1L, 0L, 1L, 10L, 300L, 50006789999999999L, System.Int64.MaxValue - 2, System.Int64.MaxValue - 1, System.Int64.MaxValue };
System.String[] prefixVals = new System.String[vals.Length];
for (int i = 0; i < vals.Length; i++)
{
prefixVals[i] = NumericUtils.LongToPrefixCoded(vals[i]);
// check forward and back conversion
Assert.AreEqual(vals[i], NumericUtils.PrefixCodedToLong(prefixVals[i]), "forward and back conversion should generate same long");
// test if decoding values as int fails correctly
Assert.Throws <FormatException>(() => NumericUtils.PrefixCodedToInt(prefixVals[i]),
"decoding a prefix coded long value as int should fail");
}
// check sort order (prefixVals should be ascending)
for (int i = 1; i < prefixVals.Length; i++)
{
Assert.IsTrue(String.CompareOrdinal(prefixVals[i - 1], prefixVals[i]) < 0, "check sort order");
}
// check the prefix encoding, lower precision should have the difference to original value equal to the lower removed bits
for (int i = 0; i < vals.Length; i++)
{
for (int j = 0; j < 64; j++)
{
long prefixVal = NumericUtils.PrefixCodedToLong(NumericUtils.LongToPrefixCoded(vals[i], j));
long mask = (1L << j) - 1L;
Assert.AreEqual(vals[i] & mask, vals[i] - prefixVal, "difference between prefix val and original value for " + vals[i] + " with shift=" + j);
}
}
}
public virtual void TestLongConversionAndOrdering()
{
// generate a series of encoded longs, each numerical one bigger than the one before
System.String last = null;
for (long l = -100000L; l < 100000L; l++)
{
System.String act = NumericUtils.LongToPrefixCoded(l);
if (last != null)
{
// test if smaller
Assert.IsTrue(String.CompareOrdinal(last, act) < 0, "actual bigger than last");
}
// test is back and forward conversion works
Assert.AreEqual(l, NumericUtils.PrefixCodedToLong(act), "forward and back conversion should generate same long");
// next step
last = act;
}
}