ARTEMIS-3294 Fix conversion of messages with a text body

artemis-server/src/main/java/org/apache/activemq/artemis/core/management/impl/openmbean/OpenTypeSupport.java

@@ -293,8 +293,8 @@ public Map<String, Object> getFields(MessageReference ref, int valueSizeLimit) t
             if (m.containsProperty(Message.HDR_LARGE_COMPRESSED)) {
                rc.put(CompositeDataConstants.TEXT_BODY, "[compressed]");
             } else {
-               final String text = m.getReadOnlyBodyBuffer().readString();
-               rc.put(CompositeDataConstants.TEXT_BODY, text != null ? JsonUtil.truncate(text, valueSizeLimit) : "");
+               SimpleString text = m.getReadOnlyBodyBuffer().readNullableSimpleString();
+               rc.put(CompositeDataConstants.TEXT_BODY, text != null ? JsonUtil.truncate(text.toString(), valueSizeLimit) : "");
             }
          } else {
             rc.put(CompositeDataConstants.TEXT_BODY, "[large message]");

artemis-server/src/test/java/org/apache/activemq/artemis/core/management/impl/openmbean/OpenTypeSupportTest.java

@@ -0,0 +1,46 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.activemq.artemis.core.management.impl.openmbean;
+
+import org.apache.activemq.artemis.api.core.Message;
+import org.apache.activemq.artemis.api.core.SimpleString;
+import org.apache.activemq.artemis.core.message.impl.CoreMessage;
+import org.apache.activemq.artemis.core.server.impl.MessageReferenceImpl;
+import org.apache.activemq.artemis.reader.TextMessageUtil;
+import org.junit.Assert;
+import org.junit.Test;
+
+import javax.management.openmbean.CompositeData;
+import javax.management.openmbean.OpenDataException;
+
+public class OpenTypeSupportTest {
+
+   @Test
+   public void testTextBody() throws OpenDataException {
+      final String bodyText = "TEST";
+      CoreMessage coreMessage = new CoreMessage();
+      coreMessage.initBuffer(1024);
+      coreMessage.setType(Message.TEXT_TYPE);
+
+      TextMessageUtil.writeBodyText(coreMessage.getBodyBuffer(), SimpleString.toSimpleString(bodyText));
+
+      CompositeData cd = OpenTypeSupport.convert(new MessageReferenceImpl(coreMessage, null), 256);
+
+      Assert.assertEquals(bodyText, cd.get("text"));
+   }
+}