diff --git a/inlong-sdk/transform-sdk/src/main/java/org/apache/inlong/sdk/transform/process/function/EltFunction.java b/inlong-sdk/transform-sdk/src/main/java/org/apache/inlong/sdk/transform/process/function/EltFunction.java new file mode 100644 index 0000000000..4eae49423c --- /dev/null +++ b/inlong-sdk/transform-sdk/src/main/java/org/apache/inlong/sdk/transform/process/function/EltFunction.java @@ -0,0 +1,67 @@ +/* + * 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.inlong.sdk.transform.process.function; + +import org.apache.inlong.sdk.transform.decode.SourceData; +import org.apache.inlong.sdk.transform.process.Context; +import org.apache.inlong.sdk.transform.process.operator.OperatorTools; +import org.apache.inlong.sdk.transform.process.parser.ValueParser; + +import net.sf.jsqlparser.expression.Expression; +import net.sf.jsqlparser.expression.Function; + +import java.util.ArrayList; +import java.util.List; + +/** + * EltFunction -> elt(index, expr[, exprs]*) + * description: + * - Returns the index-th expression. + * - index must be an integer between 1 and the number of expressions. + * - Returns NULL if index is NULL or out of range. + */ +@TransformFunction(names = {"elt"}) +public class EltFunction implements ValueParser { + + private ValueParser indexParser; + private List exprParsers; + + public EltFunction(Function expr) { + List expressions = expr.getParameters().getExpressions(); + indexParser = OperatorTools.buildParser(expressions.get(0)); + exprParsers = new ArrayList<>(); + for (int i = 1; i < expressions.size(); i++) { + exprParsers.add(OperatorTools.buildParser(expressions.get(i))); + } + } + + @Override + public Object parse(SourceData sourceData, int rowIndex, Context context) { + Object indexObject = indexParser.parse(sourceData, rowIndex, context); + if (indexObject == null) { + return null; + } + + int index = OperatorTools.parseBigDecimal(indexObject).intValue(); + if (index < 1 || index > exprParsers.size()) { + return null; + } + + return exprParsers.get(index - 1).parse(sourceData, rowIndex, context); + } +} \ No newline at end of file diff --git a/inlong-sdk/transform-sdk/src/test/java/org/apache/inlong/sdk/transform/process/function/string/TestEltFunction.java b/inlong-sdk/transform-sdk/src/test/java/org/apache/inlong/sdk/transform/process/function/string/TestEltFunction.java new file mode 100644 index 0000000000..c82e141e0c --- /dev/null +++ b/inlong-sdk/transform-sdk/src/test/java/org/apache/inlong/sdk/transform/process/function/string/TestEltFunction.java @@ -0,0 +1,85 @@ +/* + * 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.inlong.sdk.transform.process.function.string; + +import org.apache.inlong.sdk.transform.decode.SourceDecoderFactory; +import org.apache.inlong.sdk.transform.encode.SinkEncoderFactory; +import org.apache.inlong.sdk.transform.pojo.TransformConfig; +import org.apache.inlong.sdk.transform.process.TransformProcessor; + +import org.junit.Assert; +import org.junit.Test; + +import java.util.HashMap; +import java.util.List; + +public class TestEltFunction extends AbstractFunctionStringTestBase { + + @Test + public void testEltFunction() throws Exception { + String transformSql = null, data = null; + TransformConfig config = null; + TransformProcessor processor = null; + List output = null; + + // case1: elt(2, 'a', 'b', 'c') + transformSql = "select elt(numeric1, string1, string2, string3) from source"; + config = new TransformConfig(transformSql); + processor = TransformProcessor + .create(config, SourceDecoderFactory.createCsvDecoder(csvSource), + SinkEncoderFactory.createKvEncoder(kvSink)); + data = "a|b|c|2"; + output = processor.transform(data, new HashMap<>()); + Assert.assertEquals(1, output.size()); + Assert.assertEquals("result=b", output.get(0)); + + // case2: elt(4, 'a', 'b', 'c') - index out of range + data = "a|b|c|4"; + output = processor.transform(data, new HashMap<>()); + Assert.assertEquals(1, output.size()); + Assert.assertEquals("result=", output.get(0)); + + // case3: elt(null, 'a', 'b', 'c') - index is null + data = "a|b|c|"; + output = processor.transform(data, new HashMap<>()); + Assert.assertEquals(1, output.size()); + Assert.assertEquals("result=", output.get(0)); + + // case4: elt(2, 1, 2, 3) - expressions are numbers + transformSql = "select elt(numeric1, numeric1, numeric2, numeric3) from source"; + config = new TransformConfig(transformSql); + processor = TransformProcessor + .create(config, SourceDecoderFactory.createCsvDecoder(csvSource), + SinkEncoderFactory.createKvEncoder(kvSink)); + data = "a|b|c|2|2|3"; + output = processor.transform(data, new HashMap<>()); + Assert.assertEquals(1, output.size()); + Assert.assertEquals("result=2", output.get(0)); + + // case5: elt(1, 'a', 2, 'c') - mixed types + transformSql = "select elt(numeric1, string1, numeric1, string2) from source"; + config = new TransformConfig(transformSql); + processor = TransformProcessor + .create(config, SourceDecoderFactory.createCsvDecoder(csvSource), + SinkEncoderFactory.createKvEncoder(kvSink)); + data = "a|2|c|1"; + output = processor.transform(data, new HashMap<>()); + Assert.assertEquals(1, output.size()); + Assert.assertEquals("result=a", output.get(0)); + } +} \ No newline at end of file