Fix issue with some attribtues causing NPE under REST and WLS (#115)

* Fix issue with some attribtues causing NPE under REST and WLS
* minor javadoc

Author: Tim Middleton

coherence-visualvm-plugin/src/main/java/com/oracle/coherence/plugin/visualvm/tablemodel/model/AbstractData.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2024 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2025 Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -112,6 +112,31 @@ protected void preProcessReporterData(VisualVMModel model)
         {
         }
 
+    /**
+     * Returns the string representation of a {@link JsonNode} and key.
+     * @param node {@link JsonNode} to inspect
+     * @param sKey key to retrieve
+     * @return the string representation
+     */
+    protected String getSafeValue(JsonNode node, String sKey)
+        {
+        return getSafeValue(node, sKey, null);
+        }
+
+    /**
+     * Returns the string representation of a {@link JsonNode} and key.
+     * @param node {@link JsonNode} to inspect
+     * @param sKey key to retrieve
+     * @param sDefault default value
+     *
+     * @return the string representation
+     */
+    protected String getSafeValue(JsonNode node, String sKey, String sDefault)
+        {
+        JsonNode jsonNode = node.get(sKey);
+        return jsonNode != null ? jsonNode.asText() : sDefault;
+        }
+
     /**
      * {@inheritDoc}
      */

coherence-visualvm-plugin/src/main/java/com/oracle/coherence/plugin/visualvm/tablemodel/model/CacheDetailData.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2024 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2025 Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -282,10 +282,11 @@ public SortedMap<Object, Data> getAggregatedDataFromHttpQueryingInternal(
                             Long.valueOf(nodeCacheMember.get("cacheHits").asText()));
                     data.setColumn(CacheDetailData.CACHE_MISSES,
                             Integer.valueOf(nodeCacheMember.get("cacheMisses").asText()));
+
                     data.setColumn(CacheDetailData.CACHE_PRUNES,
-                            Long.valueOf(nodeCacheMember.get("cachePrunes").asText()));
+                            Long.valueOf(getSafeValue(nodeCacheMember, "cachePrunes", "0")));
                     data.setColumn(CacheDetailData.CACHE_PRUNES_MILLIS,
-                            Long.valueOf(nodeCacheMember.get("cachePrunesMillis").asText()));
+                            Long.valueOf(getSafeValue(nodeCacheMember, "cachePrunesMillis", "0")));
                     data.setColumn(CacheDetailData.HIT_PROBABILITY,
                             Float.valueOf(nodeCacheMember.get("hitProbability").floatValue()));
 

coherence-visualvm-plugin/src/main/java/com/oracle/coherence/plugin/visualvm/tablemodel/model/MemberData.java

@@ -191,8 +191,8 @@ public SortedMap<Object, Data> getAggregatedDataFromHttpQuerying(VisualVMModel m
                 data.setColumn(MemberData.USED_MEMORY,
                         (Integer) data.getColumn(MemberData.MAX_MEMORY)
                                 - (Integer) data.getColumn(MemberData.FREE_MEMORY));
-                data.setColumn(MemberData.MACHINE_NAME, clusterMember.get("machineName").asText());
-                data.setColumn(MemberData.UNICAST_ADDRESS, clusterMember.get("uncasstAddress").asText());
+                data.setColumn(MemberData.MACHINE_NAME, getSafeValue(clusterMember, "machineName"));
+                data.setColumn(MemberData.UNICAST_ADDRESS, clusterMember.get("unicastAddress").asText());
                 data.setColumn(MemberData.ROLE_NAME, clusterMember.get("roleName").asText());
                 data.setColumn(MemberData.PRODUCT_EDITION, clusterMember.get("productEdition").asText());
                 data.setColumn(MemberData.PORT, Integer.valueOf(getNumberValue(clusterMember.get("unicastPort").asText())));