improve reduce type signature

andimarek · andimarek · commit 7d39dafbc40d · 2017-08-29T08:53:17.000+02:00
diff --git a/src/main/java/graphql/analysis/MaximumQueryDepthInstrumentation.java b/src/main/java/graphql/analysis/MaximumQueryDepthInstrumentation.java
@@ -32,7 +32,7 @@ public InstrumentationContext<List<ValidationError>> beginValidation(Instrumenta
                     getOperationResult.fragmentsByName,
                     parameters.getVariables()
             );
-            int depth = (int) queryTraversal.reducePreOrder((env, acc) -> Math.max(getPathLength(env.getPath()), (Integer) acc), 0);
+            int depth = queryTraversal.reducePreOrder((env, acc) -> Math.max(getPathLength(env.getPath()), acc), 0);
             if (depth > maxDepth) {
                 throw new AbortExecutionException("maximum query depth exceeded " + depth + " > " + maxDepth);
             }
diff --git a/src/main/java/graphql/analysis/QueryTraversal.java b/src/main/java/graphql/analysis/QueryTraversal.java
@@ -51,18 +51,18 @@ public void visitPreOrder(QueryVisitor visitor) {
         visitImpl(visitor, operationDefinition.getSelectionSet(), schema.getQueryType(), null, true);
     }
 
-    public Object reducePostOrder(QueryReducer queryReducer, Object initialValue) {
+    public <T> T reducePostOrder(QueryReducer<T> queryReducer, T initialValue) {
         // compiler hack to make acc final and mutable :-)
         final Object[] acc = {initialValue};
-        visitPostOrder((env) -> acc[0] = queryReducer.reduceField(env, acc[0]));
-        return acc[0];
+        visitPostOrder((env) -> acc[0] = queryReducer.reduceField(env, (T) acc[0]));
+        return (T) acc[0];
     }
 
-    public Object reducePreOrder(QueryReducer queryReducer, Object initialValue) {
+    public <T> T reducePreOrder(QueryReducer<T> queryReducer, T initialValue) {
         // compiler hack to make acc final and mutable :-)
         final Object[] acc = {initialValue};
-        visitPreOrder((env) -> acc[0] = queryReducer.reduceField(env, acc[0]));
-        return acc[0];
+        visitPreOrder((env) -> acc[0] = queryReducer.reduceField(env, (T) acc[0]));
+        return (T) acc[0];
     }
 
 

Original file line number	Diff line number	Diff line change
`@@ -32,7 +32,7 @@ public InstrumentationContext<List<ValidationError>> beginValidation(Instrumenta`
`32`	`32`	`getOperationResult.fragmentsByName,`
`33`	`33`	`parameters.getVariables()`
`34`	`34`	`);`
`35`		`- int depth = (int) queryTraversal.reducePreOrder((env, acc) -> Math.max(getPathLength(env.getPath()), (Integer) acc), 0);`
	`35`	`+ int depth = queryTraversal.reducePreOrder((env, acc) -> Math.max(getPathLength(env.getPath()), acc), 0);`
`36`	`36`	`if (depth > maxDepth) {`
`37`	`37`	`throw new AbortExecutionException("maximum query depth exceeded " + depth + " > " + maxDepth);`
`38`	`38`	`}`