Unify field order in toString methods

Author: malczuuu

problem4j-core/src/main/java/io/github/problem4j/core/AbstractProblem.java

@@ -224,9 +224,13 @@ public String toString() {
       entries.add("\"instance\" : \"" + escape(getInstance().toString()) + "\"");
     }
 
-    getExtensionMembers()
+    getExtensionMembers().entrySet().stream()
+        .sorted(Map.Entry.comparingByKey())
         .forEach(
-            (field, value) -> {
+            entry -> {
+              String field = entry.getKey();
+              Object value = entry.getValue();
+
               if (value == null) {
                 return;
               }

problem4j-core/src/main/java/io/github/problem4j/core/AbstractProblemBuilder.java

@@ -289,20 +289,25 @@ public String toString() {
       entries.add("\"instance\" : \"" + escape(instance.toString()) + "\"");
     }
 
-    extensions.forEach(
-        (field, value) -> {
-          if (value == null) {
-            return;
-          }
+    extensions.entrySet().stream()
+        .sorted(Map.Entry.comparingByKey())
+        .forEach(
+            entry -> {
+              String field = entry.getKey();
+              Object value = entry.getValue();
 
-          if (value instanceof String) {
-            entries.add("\"" + field + "\" : \"" + escape((String) value) + "\"");
-          } else if (value instanceof Number || value instanceof Boolean) {
-            entries.add("\"" + field + "\" : " + value);
-          } else {
-            entries.add(getObjectLine(field, value));
-          }
-        });
+              if (value == null) {
+                return;
+              }
+
+              if (value instanceof String) {
+                entries.add("\"" + field + "\" : \"" + escape((String) value) + "\"");
+              } else if (value instanceof Number || value instanceof Boolean) {
+                entries.add("\"" + field + "\" : " + value);
+              } else {
+                entries.add(getObjectLine(field, value));
+              }
+            });
 
     return entries.isEmpty()
         ? "{ }"

problem4j-core/src/main/java/io/github/problem4j/core/AbstractProblemContext.java

@@ -163,6 +163,7 @@ public String toString() {
       return "{ }";
     }
     return toMap().entrySet().stream()
+        .sorted(Map.Entry.comparingByKey())
         .map(this::toEntryLine)
         .collect(Collectors.joining(", ", "{ ", " }"));
   }