alejandro-anadon commented on code in PR #1458: URL: https://github.com/apache/phoenix/pull/1458#discussion_r969410865
########## phoenix-core/src/main/java/org/apache/phoenix/expression/function/StringToUUIDFunction.java: ########## @@ -0,0 +1,112 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to you under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.phoenix.expression.function; + +import java.nio.charset.Charset; +import java.sql.SQLException; +import java.util.List; +import java.util.UUID; + +import org.apache.hadoop.hbase.io.ImmutableBytesWritable; +import org.apache.phoenix.expression.Expression; +import org.apache.phoenix.parse.FunctionParseNode.Argument; +import org.apache.phoenix.parse.FunctionParseNode.BuiltInFunction; +import org.apache.phoenix.schema.SortOrder; +import org.apache.phoenix.schema.tuple.Tuple; +import org.apache.phoenix.schema.types.PBinary; +import org.apache.phoenix.schema.types.PDataType; +import org.apache.phoenix.schema.types.PUUID; +import org.apache.phoenix.schema.types.PVarchar; +import org.apache.phoenix.util.UUIDUtil; + +/** + * ScalarFunction {@link ScalarFunction}. Receives a String parameter and returns a UUID. + * for example: + * SELECT STR_TO_UUID('be791257-6764-45a5-9719-cc50bf7938e4'); + * inverse function to {@link UUIDToStringFunction} + * Related to {@link UUIDRandomFunction}. + */ +@BuiltInFunction(name = StringToUUIDFunction.NAME, + args = { @Argument(allowedTypes = { PVarchar.class }) }) +public class StringToUUIDFunction extends ScalarFunction { + public static final String NAME = "STR_TO_UUID"; + + // "00000000-0000-0000-0000-000000000000".length() == 36 + private static final int UUID_TEXTUAL_LENGTH = 36; + + + public StringToUUIDFunction() { + } + + public StringToUUIDFunction(List<Expression> children) throws SQLException { + super(children); + } + + private Expression getStringExpression() { + return children.get(0); + } + + @Override + public boolean evaluate(Tuple tuple, ImmutableBytesWritable ptr) { + if (!getStringExpression().evaluate(tuple, ptr)) { + return false; + } + + if (ptr.getLength() != UUID_TEXTUAL_LENGTH) { + throw new IllegalArgumentException("Invalid UUID string: " + new String(ptr.get(), + ptr.getOffset(), ptr.getLength(), Charset.forName("UTF-8"))); + } + + String value; + + // Next is done because, if not,"org.apache.phoenix.expression.function.UUIDFunctionTest", + // test "testUUIDFuntions" fails when + // "testStringToUUIDfunction(uuidStr, null, SortOrder.DESC)" + // is used (maybe stupid or bad designed test?). + // + // But I think that in real world it is not necessary. + // + // without check 'ptr.get()[ptr.getOffset() + 8] == '-'' , just only with: + // 'value = new String(ptr.get(), ptr.getOffset(), 36);' other tests works fine. + // but placed because not sure (may be removed?). + + if (ptr.get()[ptr.getOffset() + 8] == '-') { Review Comment: I am one hundred percent agree. I don't like doing it that way. But I did not find any way to know if it is ordered ASC or DESC. It is not in the parameters 'public boolean evaluate(Tuple tuple, ImmutableBytesWritable ptr)'; and that is the (very primitive) way I found how to solve it. If there is a way, I couldn't find it. If there is and you give me a hint, I can change it to a more elegant way. On the other hand, I don't know if in real world, this function can be reached in DESC mode. I only got it by forcing in the 'org.apache.phoenix.expression.function.UUIDFunctionTest' test when I call "testStringToUUIDfunction(uuidStr, null, SortOrder.DESC)" , which I have my doubts if it makes sense in the real world. If it doesn't make sense, I can remove the check "if (ptr.get()[ptr.getOffset() + 8] == '-')'" in the class, and the call it in the test. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
