[INLONG-10971][SDK] Transform support INSERT function (#10972)

inlong-sdk/transform-sdk/src/main/java/org/apache/inlong/sdk/transform/process/function/InsertFunction.java

@@ -0,0 +1,101 @@
+/*
+ * 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.List;
+/**
+ * InsertFunction
+ *
+ * Description:
+ * Returns a string where a specified substring is replaced by another string, starting at a given position and for a specified length.
+ * If the position is out of the string's bounds, the original string is returned.
+ * If the length exceeds the remaining length of the string from the given position, the replacement continues to the end of the string.
+ * If any argument is null, the function returns null.
+ *
+ * Arguments:
+ * - str: The original string.
+ * - pos: The position to start the replacement (1-based index).
+ * - len: The number of characters to replace.
+ * - newstr: The string to insert.
+ *
+ * Examples:
+ * - INSERT('12345678', 3, 4, 'word') = '12word78'
+ * - INSERT('12345678', -1, 4, 'word') = '12345678'
+ * - INSERT('12345678', 3, 100, 'word') = '12word'
+ */
+@TransformFunction(names = {"insert"})
+public class InsertFunction implements ValueParser {
+
+    private ValueParser strParser;
+    private ValueParser posParser;
+    private ValueParser lenParser;
+    private ValueParser newStrParser;
+
+    public InsertFunction(Function expr) {
+        List<Expression> expressions = expr.getParameters().getExpressions();
+        strParser = OperatorTools.buildParser(expressions.get(0));
+        posParser = OperatorTools.buildParser(expressions.get(1));
+        lenParser = OperatorTools.buildParser(expressions.get(2));
+        newStrParser = OperatorTools.buildParser(expressions.get(3));
+    }
+
+    @Override
+    public Object parse(SourceData sourceData, int rowIndex, Context context) {
+        Object strObject = strParser.parse(sourceData, rowIndex, context);
+        Object posObject = posParser.parse(sourceData, rowIndex, context);
+        Object lenObject = lenParser.parse(sourceData, rowIndex, context);
+        Object newStrObject = newStrParser.parse(sourceData, rowIndex, context);
+
+        if (strObject == null || posObject == null || lenObject == null || newStrObject == null) {
+            return null;
+        }
+
+        String str = OperatorTools.parseString(strObject);
+        int pos = OperatorTools.parseBigDecimal(posObject).intValue();
+        int len = OperatorTools.parseBigDecimal(lenObject).intValue();
+        String newStr = OperatorTools.parseString(newStrObject);
+
+        if (str == null || newStr == null) {
+            return null;
+        }
+
+        if (pos < 1 || pos > str.length()) {
+            return str;
+        }
+
+        int startIndex = pos - 1;
+        int endIndex = Math.min(startIndex + len, str.length());
+
+        StringBuilder result = new StringBuilder();
+        result.append(str, 0, startIndex);
+        result.append(newStr);
+        if (endIndex < str.length()) {
+            result.append(str, endIndex, str.length());
+        }
+
+        return result.toString();
+    }
+}

inlong-sdk/transform-sdk/src/test/java/org/apache/inlong/sdk/transform/process/TestTransformStringFunctionsProcessor.java

@@ -690,4 +690,38 @@ public void testTranslateFunction() throws Exception {
         Assert.assertEquals(output3.get(0), "result=Apache Inlong");
     }
 
+    @Test
+    public void testInsertFunction() throws Exception {
+        String transformSql1 = "select insert(string1, numeric1, numeric2, string2) from source";
+        TransformConfig config1 = new TransformConfig(transformSql1);
+        TransformProcessor<String, String> processor1 = TransformProcessor
+                .create(config1, SourceDecoderFactory.createCsvDecoder(csvSource),
+                        SinkEncoderFactory.createKvEncoder(kvSink));
+
+        // case1: insert('12345678', 3, 4, 'word') -> '12word78'
+        List<String> output1 = processor1.transform("12345678|word|cloud|3|4|0", new HashMap<>());
+        Assert.assertEquals(1, output1.size());
+        Assert.assertEquals("result=12word78", output1.get(0));
+
+        // case2: insert('12345678', -1, 4, 'word') -> '12345678'
+        List<String> output2 = processor1.transform("12345678|word|cloud|-1|4|0", new HashMap<>());
+        Assert.assertEquals(1, output2.size());
+        Assert.assertEquals("result=12345678", output2.get(0));
+
+        // case3: insert('12345678', 3, 100, 'word') -> '12word'
+        List<String> output3 = processor1.transform("12345678|word|cloud|3|100|0", new HashMap<>());
+        Assert.assertEquals(1, output3.size());
+        Assert.assertEquals("result=12word", output3.get(0));
+
+        // case4: insert('', 3, 4, 'word') -> ''
+        List<String> output4 = processor1.transform("|word|cloud|3|4|0", new HashMap<>());
+        Assert.assertEquals(1, output4.size());
+        Assert.assertEquals("result=", output4.get(0));
+
+        // case5: insert('12345678', 3, 4, '') -> '1278'
+        List<String> output5 = processor1.transform("12345678||cloud|3|4|0", new HashMap<>());
+        Assert.assertEquals(1, output5.size());
+        Assert.assertEquals("result=1278", output5.get(0));
+    }
+
 }