Provide an implementation of JsonComparator

See gh-32791

Author: snicoll

spring-test/src/main/java/org/springframework/test/json/JsonAssert.java

@@ -16,13 +16,14 @@
 
 package org.springframework.test.json;
 
+import org.json.JSONException;
 import org.skyscreamer.jsonassert.JSONCompare;
 import org.skyscreamer.jsonassert.JSONCompareMode;
 import org.skyscreamer.jsonassert.JSONCompareResult;
+import org.skyscreamer.jsonassert.comparator.DefaultComparator;
 import org.skyscreamer.jsonassert.comparator.JSONComparator;
 
 import org.springframework.lang.Nullable;
-import org.springframework.util.function.ThrowingBiFunction;
 
 /**
  * Useful methods that can be used with {@code org.skyscreamer.jsonassert}.
@@ -40,7 +41,9 @@ public abstract class JsonAssert {
 	 * @see JSONCompareMode#LENIENT
 	 */
 	public static JsonComparator comparator(JsonCompareMode compareMode) {
-		return comparator(toJSONCompareMode(compareMode));
+		JSONCompareMode jsonAssertCompareMode = (compareMode != JsonCompareMode.LENIENT
+				? JSONCompareMode.STRICT : JSONCompareMode.LENIENT);
+		return comparator(jsonAssertCompareMode);
 	}
 
 	/**
@@ -50,8 +53,7 @@ public static JsonComparator comparator(JsonCompareMode compareMode) {
 	 * @return a new {@link JsonComparator} instance
 	 */
 	public static JsonComparator comparator(JSONComparator comparator) {
-		return comparator((expectedJson, actualJson) -> JSONCompare
-				.compareJSON(expectedJson, actualJson, comparator));
+		return new JsonAssertJsonComparator(comparator);
 	}
 
 	/**
@@ -61,33 +63,41 @@ public static JsonComparator comparator(JSONComparator comparator) {
 	 * @return a new {@link JsonComparator} instance
 	 */
 	public static JsonComparator comparator(JSONCompareMode mode) {
-		return comparator((expectedJson, actualJson) -> JSONCompare
-				.compareJSON(expectedJson, actualJson, mode));
+		return new JsonAssertJsonComparator(mode);
 	}
 
-	private static JsonComparator comparator(ThrowingBiFunction<String, String, JSONCompareResult> compareFunction) {
-		return (expectedJson, actualJson) -> compare(expectedJson, actualJson, compareFunction);
-	}
+	private static class JsonAssertJsonComparator implements JsonComparator {
 
-	private static JsonComparison compare(@Nullable String expectedJson, @Nullable String actualJson,
-			ThrowingBiFunction<String, String, JSONCompareResult> compareFunction) {
+		private final JSONComparator jsonAssertComparator;
 
-		if (actualJson == null) {
-			return (expectedJson != null)
-					? JsonComparison.mismatch("Expected null JSON")
-					: JsonComparison.match();
+		JsonAssertJsonComparator(JSONComparator jsonAssertComparator) {
+			this.jsonAssertComparator = jsonAssertComparator;
 		}
-		if (expectedJson == null) {
-			return JsonComparison.mismatch("Expected non-null JSON");
+
+		JsonAssertJsonComparator(JSONCompareMode compareMode) {
+			this(new DefaultComparator(compareMode));
 		}
-		JSONCompareResult result = compareFunction.throwing(IllegalStateException::new).apply(expectedJson, actualJson);
-		return (!result.passed())
-				? JsonComparison.mismatch(result.getMessage())
-				: JsonComparison.match();
-	}
 
-	private static JSONCompareMode toJSONCompareMode(JsonCompareMode compareMode) {
-		return (compareMode != JsonCompareMode.LENIENT ? JSONCompareMode.STRICT : JSONCompareMode.LENIENT);
+		@Override
+		public JsonComparison compare(@Nullable String expectedJson, @Nullable String actualJson) {
+			if (actualJson == null) {
+				return (expectedJson != null)
+						? JsonComparison.mismatch("Expected null JSON")
+						: JsonComparison.match();
+			}
+			if (expectedJson == null) {
+				return JsonComparison.mismatch("Expected non-null JSON");
+			}
+			try {
+				JSONCompareResult result = JSONCompare.compareJSON(expectedJson, actualJson, this.jsonAssertComparator);
+				return (!result.passed())
+						? JsonComparison.mismatch(result.getMessage())
+						: JsonComparison.match();
+			}
+			catch (JSONException ex) {
+				throw new IllegalStateException(ex);
+			}
+		}
 	}
 
 }