Update after Luca review (2)

Author: tlrx

core/src/main/java/org/elasticsearch/ElasticsearchException.java

@@ -405,20 +405,19 @@ public static ElasticsearchException fromXContent(XContentParser parser) throws
     }
 
     private static ElasticsearchException innerFromXContent(XContentParser parser) throws IOException {
+        XContentParser.Token token = parser.currentToken();
+        ensureExpectedToken(XContentParser.Token.FIELD_NAME, token, parser::getTokenLocation);
+
         String type = null, reason = null, stack = null;
         ElasticsearchException cause = null;
         Map<String, List<String>> metadata = new HashMap<>();
         Map<String, List<String>> headers = new HashMap<>();
 
-        XContentParser.Token token = parser.currentToken();
-        String currentFieldName = parser.currentName();
-        do {
-            if (token == XContentParser.Token.FIELD_NAME) {
-                currentFieldName = parser.currentName();
-                token = parser.nextToken();
-            }
+        for (; token == XContentParser.Token.FIELD_NAME; token = parser.nextToken()) {
+            String currentFieldName = parser.currentName();
+            token = parser.nextToken();
 
-            if (token != null && token.isValue()) {
+            if (token.isValue()) {
                 if (TYPE.equals(currentFieldName)) {
                     type = parser.text();
                 } else if (REASON.equals(currentFieldName)) {
@@ -432,18 +431,25 @@ private static ElasticsearchException innerFromXContent(XContentParser parser) t
                 if (CAUSED_BY.equals(currentFieldName)) {
                     cause = fromXContent(parser);
                 } else if (HEADER.equals(currentFieldName)) {
-                    Map<String, Object> headerMap = parser.map();
-                    if (headerMap != null) {
-                        for (Map.Entry<String, Object> header : headerMap.entrySet()) {
-                            List<String> values = headers.getOrDefault(header.getKey(), new ArrayList<>());
-                            if (header.getValue() instanceof Iterable) {
-                                for (Object value : (Iterable) header.getValue()) {
-                                    values.add(String.valueOf(value));
+                    while ((token = parser.nextToken()) != XContentParser.Token.END_OBJECT) {
+                        if (token == XContentParser.Token.FIELD_NAME) {
+                            currentFieldName = parser.currentName();
+                        } else {
+                            List<String> values = headers.getOrDefault(currentFieldName, new ArrayList<>());
+                            if (token.isValue() || token == XContentParser.Token.VALUE_NULL) {
+                                values.add(parser.textOrNull());
+                            } else if (token == XContentParser.Token.START_ARRAY) {
+                                while ((token = parser.nextToken()) != XContentParser.Token.END_ARRAY) {
+                                    if (token.isValue() || token == XContentParser.Token.VALUE_NULL) {
+                                        values.add(parser.textOrNull());
+                                    } else {
+                                        parser.skipChildren();
+                                    }
                                 }
-                            } else {
-                                values.add(String.valueOf(header.getValue()));
+                            } else if (token == XContentParser.Token.START_ARRAY) {
+                                parser.skipChildren();
                             }
-                            headers.put(header.getKey(), values);
+                            headers.put(currentFieldName, values);
                         }
                     }
                 } else {
@@ -470,7 +476,7 @@ private static ElasticsearchException innerFromXContent(XContentParser parser) t
                     metadata.put(currentFieldName, values);
                 }
             }
-        } while ((token = parser.nextToken()) == XContentParser.Token.FIELD_NAME);
+        }
 
         StringBuilder message = new StringBuilder("Elasticsearch exception [");
         message.append(TYPE).append('=').append(type).append(", ");

core/src/test/java/org/elasticsearch/ElasticsearchExceptionTests.java

@@ -543,7 +543,7 @@ public void testThrowableToAndFromXContent() throws IOException {
         assertNotNull(parsedException);
 
         ElasticsearchException expected = exceptions.v2();
-        while (expected != null) {
+        do {
             assertEquals(expected.getMessage(), parsedException.getMessage());
             assertEquals(expected.getHeaders(), parsedException.getHeaders());
             assertEquals(expected.getMetadata(), parsedException.getMetadata());
@@ -555,7 +555,7 @@ public void testThrowableToAndFromXContent() throws IOException {
             if (expected == null) {
                 assertNull(parsedException);
             }
-        }
+        } while (expected != null);
     }
 
     /**
@@ -633,10 +633,11 @@ private static Tuple<Throwable, ElasticsearchException> randomExceptions() {
         }
 
         if (actual instanceof ElasticsearchException) {
+            ElasticsearchException actualException = (ElasticsearchException) actual;
             if (randomBoolean()) {
-                Map<String, List<String>> randomHeaders = new HashMap<>();
-
                 int nbHeaders = randomIntBetween(1, 5);
+                Map<String, List<String>> randomHeaders = new HashMap<>(nbHeaders);
+
                 for (int i = 0; i < nbHeaders; i++) {
                     List<String> values = new ArrayList<>();
 
@@ -648,15 +649,15 @@ private static Tuple<Throwable, ElasticsearchException> randomExceptions() {
                 }
 
                 for (Map.Entry<String, List<String>> entry : randomHeaders.entrySet()) {
-                    ((ElasticsearchException) actual).addHeader(entry.getKey(), entry.getValue());
+                    actualException.addHeader(entry.getKey(), entry.getValue());
                     expected.addHeader(entry.getKey(), entry.getValue());
                 }
             }
 
             if (randomBoolean()) {
-                Map<String, List<String>> randomMetadata = new HashMap<>();
-
                 int nbMetadata = randomIntBetween(1, 5);
+                Map<String, List<String>> randomMetadata = new HashMap<>(nbMetadata);
+
                 for (int i = 0; i < nbMetadata; i++) {
                     List<String> values = new ArrayList<>();
 
@@ -668,7 +669,7 @@ private static Tuple<Throwable, ElasticsearchException> randomExceptions() {
                 }
 
                 for (Map.Entry<String, List<String>> entry : randomMetadata.entrySet()) {
-                    ((ElasticsearchException) actual).addMetadata(entry.getKey(), entry.getValue());
+                    actualException.addMetadata(entry.getKey(), entry.getValue());
                     expected.addMetadata(entry.getKey(), entry.getValue());
                 }
             }
@@ -679,13 +680,12 @@ private static Tuple<Throwable, ElasticsearchException> randomExceptions() {
                     String resourceType = "type_" + i;
                     String[] resourceIds = null;
                     if (frequently()) {
-                        resourceIds = new String[randomIntBetween(0, 3)];
+                        resourceIds = new String[randomIntBetween(1, 3)];
                         for (int j = 0; j < resourceIds.length; j++) {
                             resourceIds[j] = frequently() ? randomAsciiOfLength(5) : null;
                         }
                     }
-
-                    ((ElasticsearchException) actual).setResources(resourceType, resourceIds);
+                    actualException.setResources(resourceType, resourceIds);
                     expected.setResources(resourceType, resourceIds);
                 }
             }