[#7171] [#7276] Add support for SQL Server's CHOOSE() function

jOOQ-manual/src/main/resources/org/jooq/web/grammar-3.11.txt

@@ -534,12 +534,13 @@ term =
 | 'BIT_LENGTH' '(' field ')'
 | case
 | 'CAST' '(' field 'AS' dataType ')'
-| 'CONVERT' '(' dataType ',' field ')'
 | ( 'CEIL' | 'CEILING' ) '(' sum ')'
 | 'CHARINDEX' '(' field ',' field ')'
 | 'CHAR_LENGTH' '(' field ')'
+| 'CHOOSE' '(' field { ',' field } ')'
 | 'COALESCE' '(' fields ')'
 | 'CONCAT' '(' fields ')'
+| 'CONVERT' '(' dataType ',' field ')'
 | 'COS' '(' sum ')'
 | 'COSH' '(' sum ')'
 | 'COT' '(' sum ')'

jOOQ/src/main/java/org/jooq/impl/Choose.java

@@ -0,0 +1,96 @@
+/*
+ * Licensed 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.
+ *
+ * Other licenses:
+ * -----------------------------------------------------------------------------
+ * Commercial licenses for this work are available. These replace the above
+ * ASL 2.0 and offer limited warranties, support, maintenance, and commercial
+ * database integrations.
+ *
+ * For more information, please visit: http://www.jooq.org/licenses
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ */
+package org.jooq.impl;
+
+import static org.jooq.impl.DSL.choose;
+import static org.jooq.impl.DSL.function;
+import static org.jooq.impl.DSL.inline;
+import static org.jooq.impl.DSL.unquotedName;
+
+import org.jooq.CaseValueStep;
+import org.jooq.CaseWhenStep;
+import org.jooq.Context;
+import org.jooq.DataType;
+import org.jooq.Field;
+
+/**
+ * @author Lukas Eder
+ */
+final class Choose<T> extends AbstractField<T> {
+
+    private static final long serialVersionUID = 4861196545079661438L;
+    private Field<Integer>    index;
+    private Field<T>[]        values;
+
+    Choose(Field<Integer> index, Field<T>[] values) {
+        super(DSL.name("choose"), dataType(values));
+
+        this.index = index;
+        this.values = values;
+    }
+
+    @SuppressWarnings("unchecked")
+    private static final <T> DataType<T> dataType(Field<T>[] values) {
+        return values == null || values.length == 0 ? (DataType<T>) SQLDataType.OTHER : values[0].getDataType();
+    }
+
+    @Override
+    public final void accept(Context<?> ctx) {
+        switch (ctx.family()) {
+
+
+
+
+
+
+            default: {
+                CaseValueStep<Integer> s = choose(index);
+                CaseWhenStep<Integer, T> when = null;
+
+                for (int i = 0; i < values.length; i++) {
+                    when = when == null
+                        ? s.when(inline(i + 1), values[i])
+                        : when.when(inline(i + 1), values[i]);
+                }
+
+                ctx.visit(when);
+                break;
+            }
+        }
+    }
+}

jOOQ/src/main/java/org/jooq/impl/DSL.java

@@ -12046,6 +12046,28 @@ public class DSL {
         return decode().value(value);
     }
 
+    @Support
+    public static <T> Field<T> choose(int index, T... values) {
+        return choose(val(index), (Field<T>[]) Tools.fields(values).toArray(EMPTY_FIELD));
+    }
+
+    @Support
+    @SafeVarargs
+    public static <T> Field<T> choose(int index, Field<T>... values) {
+        return choose(val(index), values);
+    }
+
+    @Support
+    public static <T> Field<T> choose(Field<Integer> index, T... values) {
+        return choose(index, (Field<T>[]) Tools.fields(values).toArray(EMPTY_FIELD));
+    }
+
+    @Support
+    @SafeVarargs
+    public static <T> Field<T> choose(Field<Integer> index, Field<T>... values) {
+        return new Choose<T>(index, values);
+    }
+
     /**
      * Initialise a {@link Case} statement.
      * <p>

jOOQ/src/main/java/org/jooq/impl/ParserImpl.java

@@ -3886,6 +3886,8 @@ final class ParserImpl implements Parser {
                     return field;
                 else if ((field = parseFieldConvertIf(ctx)) != null)
                     return field;
+                else if ((field = parseFieldChooseIf(ctx)) != null)
+                    return field;
 
                 break;
 
@@ -5026,7 +5028,20 @@ final class ParserImpl implements Parser {
                 (Field<Object>)   fields.get(2),
                 (Field<Object>[]) (size == 3 ? EMPTY_FIELD : fields.subList(3, size).toArray(EMPTY_FIELD))
             );
+        }
 
+        return null;
+    }
+
+    private static final Field<?> parseFieldChooseIf(ParserContext ctx) {
+        if (parseFunctionNameIf(ctx, "CHOOSE")) {
+            parse(ctx, '(');
+            Field<Integer> index = (Field<Integer>) parseField(ctx, Type.N);
+            parse(ctx, ',');
+            List<Field<?>> fields = parseFields(ctx);
+            parse(ctx, ')');
+
+            return DSL.choose(index, fields.toArray(EMPTY_FIELD));
         }
 
         return null;