Add a shortcut for building aggregate function signatures.

daminichopra · Apr 2, 2020 · 547eeda · 547eeda
1 parent 6a30696
commit 547eeda
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Showing 5 changed files with 47 additions and 30 deletions.
diff --git a/sql/src/main/java/io/crate/execution/engine/aggregation/impl/ArrayAgg.java b/sql/src/main/java/io/crate/execution/engine/aggregation/impl/ArrayAgg.java
@@ -49,13 +49,11 @@ public final class ArrayAgg extends AggregationFunction<List<Object>, List<Objec
 
     public static void register(AggregationImplModule module) {
         module.register(
-            Signature.builder()
-                .name(NAME)
-                .kind(FunctionInfo.Type.AGGREGATE)
-                .argumentTypes(parseTypeSignature("E"))
-                .typeVariableConstraints(typeVariable("E"))
-                .returnType(parseTypeSignature("array(E)"))
-                .build(),
+            Signature.aggregate(
+                NAME,
+                parseTypeSignature("E"),
+                parseTypeSignature("array(E)")
+            ).withTypeVariableConstraints(typeVariable("E")),
             args -> new ArrayAgg(args.get(0))
         );
     }

diff --git a/sql/src/main/java/io/crate/execution/engine/aggregation/impl/CountAggregation.java b/sql/src/main/java/io/crate/execution/engine/aggregation/impl/CountAggregation.java
@@ -62,13 +62,11 @@ public class CountAggregation extends AggregationFunction<CountAggregation.LongS
 
     public static void register(AggregationImplModule mod) {
         mod.register(
-            Signature.builder()
-                .name(NAME)
-                .kind(FunctionInfo.Type.AGGREGATE)
-                .typeVariableConstraints(typeVariable("V"))
-                .argumentTypes(parseTypeSignature("V"))
-                .returnType(DataTypes.LONG.getTypeSignature())
-                .build(),
+            Signature.aggregate(
+                NAME,
+                parseTypeSignature("V"),
+                DataTypes.LONG.getTypeSignature()
+            ).withTypeVariableConstraints(typeVariable("V")),
             args -> new CountAggregation(
                 new FunctionInfo(
                     new FunctionIdent(NAME, args),
@@ -77,11 +75,7 @@ public static void register(AggregationImplModule mod) {
                 true)
         );
         mod.register(
-            Signature.builder()
-                .name(NAME)
-                .kind(FunctionInfo.Type.AGGREGATE)
-                .returnType(DataTypes.LONG.getTypeSignature())
-                .build(),
+            Signature.aggregate(NAME, DataTypes.LONG.getTypeSignature()),
             args -> new CountAggregation(COUNT_STAR_FUNCTION, false)
         );
     }

diff --git a/sql/src/main/java/io/crate/execution/engine/aggregation/impl/StringAgg.java b/sql/src/main/java/io/crate/execution/engine/aggregation/impl/StringAgg.java
@@ -64,14 +64,11 @@ public final class StringAgg extends AggregationFunction<StringAgg.StringAggStat
 
     public static void register(AggregationImplModule mod) {
         mod.register(
-            Signature.builder()
-                .name(NAME)
-                .kind(FunctionInfo.Type.AGGREGATE)
-                .argumentTypes(
-                    DataTypes.STRING.getTypeSignature(),
-                    DataTypes.STRING.getTypeSignature())
-                .returnType(DataTypes.STRING.getTypeSignature())
-                .build(),
+            Signature.aggregate(
+                NAME,
+                DataTypes.STRING.getTypeSignature(),
+                DataTypes.STRING.getTypeSignature(),
+                DataTypes.STRING.getTypeSignature()),
             args -> new StringAgg()
         );
     }

diff --git a/sql/src/main/java/io/crate/expression/AbstractFunctionModule.java b/sql/src/main/java/io/crate/expression/AbstractFunctionModule.java
@@ -49,14 +49,23 @@ public abstract class AbstractFunctionModule<T extends FunctionImplementation> e
     private HashMap<FunctionName, List<FuncResolver>> functionImplementations = new HashMap<>();
     private MapBinder<FunctionName, List<FuncResolver>> implementationsBinder;
 
+    /**
+     * @deprecated Use {@link #register(Signature, Function)} instead.
+     */
     public void register(T impl) {
         functions.put(impl.info().ident(), impl);
     }
 
+    /**
+     * @deprecated Use {@link #register(Signature, Function)} instead.
+     */
     public void register(String name, FunctionResolver functionResolver) {
         register(new FunctionName(name), functionResolver);
     }
 
+    /**
+     * @deprecated Use {@link #register(Signature, Function)} instead.
+     */
     public void register(FunctionName qualifiedName, FunctionResolver functionResolver) {
         resolver.put(qualifiedName, functionResolver);
     }

diff --git a/sql/src/main/java/io/crate/metadata/functions/Signature.java b/sql/src/main/java/io/crate/metadata/functions/Signature.java
@@ -33,6 +33,25 @@
 
 public final class Signature {
 
+    /**
+     * See {@link #aggregate(FunctionName, TypeSignature...)}
+     */
+    public static Signature aggregate(String name, TypeSignature... types) {
+        return scalar(new FunctionName(null, name), types);
+    }
+
+    /**
+     * Shortcut for creating a signature of type {@link FunctionInfo.Type#AGGREGATE}.
+     * The last element of the given types is handled as the return type.
+     *
+     * @param name      The fqn function name.
+     * @param types     The argument and return (last element) types
+     * @return          The created signature
+     */
+    public static Signature aggregate(FunctionName name, TypeSignature... types) {
+        return signatureBuilder(name, FunctionInfo.Type.AGGREGATE, types).build();
+    }
+
     /**
      * See {@link #scalar(FunctionName, TypeSignature...)}
      */
@@ -49,14 +68,14 @@ public static Signature scalar(String name, TypeSignature... types) {
      * @return          The created signature
      */
     public static Signature scalar(FunctionName name, TypeSignature... types) {
-        return scalarBuilder(name, types).build();
+        return signatureBuilder(name, FunctionInfo.Type.SCALAR, types).build();
     }
 
-    private static Signature.Builder scalarBuilder(FunctionName name, TypeSignature... types) {
+    private static Signature.Builder signatureBuilder(FunctionName name, FunctionInfo.Type type, TypeSignature... types) {
         assert types.length > 0 : "Types must contain at least the return type (last element), 0 types given";
         Builder builder = Signature.builder()
             .name(name)
-            .kind(FunctionInfo.Type.SCALAR)
+            .kind(type)
             .returnType(types[types.length - 1]);
         if (types.length > 1) {
             builder.argumentTypes(Arrays.copyOf(types, types.length - 1));