presto-hive/src/main/java/io/prestosql/plugin/hive/coercions/IntegerNumberToVarcharCoercer.java/IntegerNumberToVarcharCoercer/applyCoercedValue
class IntegerNumberToVarcharCoercer:    @Override
    protected void applyCoercedValue(BlockBuilder blockBuilder, Block block, int position)
    {
        toType.writeSlice(blockBuilder, utf8Slice(String.valueOf(fromType.getLong(block, position))));
    }