feat(triggers): Add support for querying mbean attributes

cryostat-core/src/main/java/io/cryostat/core/net/JFRConnection.java

@@ -33,6 +33,7 @@
 import io.cryostat.libcryostat.JvmIdentifier;
 import io.cryostat.libcryostat.net.IDException;
 import io.cryostat.libcryostat.net.MBeanMetrics;
+import io.cryostat.libcryostat.net.MbeanAttributeMap;
 import io.cryostat.libcryostat.sys.Clock;
 import io.cryostat.libcryostat.triggers.SmartTrigger;
 
@@ -87,6 +88,12 @@ public default void disableSmartTrigger(String definitions) throws ConnectionExc
         throw new ConnectionException("Unimplemented");
     }
 
+    public List<MbeanAttributeMap> queryMbeanAttributes()
+            throws IOException,
+                    InstanceNotFoundException,
+                    IntrospectionException,
+                    ReflectionException;
+
     public MBeanMetrics getMBeanMetrics()
             throws ConnectionException,
                     IOException,

cryostat-core/src/main/java/io/cryostat/core/net/JFRJMXConnection.java

@@ -31,7 +31,9 @@
 import javax.management.IntrospectionException;
 import javax.management.MBeanAttributeInfo;
 import javax.management.MBeanException;
+import javax.management.MBeanInfo;
 import javax.management.MalformedObjectNameException;
+import javax.management.ObjectInstance;
 import javax.management.ObjectName;
 import javax.management.ReflectionException;
 import javax.management.openmbean.CompositeData;
@@ -62,6 +64,8 @@
 import io.cryostat.libcryostat.JvmIdentifier;
 import io.cryostat.libcryostat.net.IDException;
 import io.cryostat.libcryostat.net.MBeanMetrics;
+import io.cryostat.libcryostat.net.MbeanAttributeMap;
+import io.cryostat.libcryostat.net.MbeanAttributeMap.MBeanAttribute;
 import io.cryostat.libcryostat.net.MemoryMetrics;
 import io.cryostat.libcryostat.net.OperatingSystemMetrics;
 import io.cryostat.libcryostat.net.RuntimeMetrics;
@@ -428,4 +432,34 @@ public ConnectionFailureException(String message) {
             super(message);
         }
     }
+
+    @Override
+    public synchronized List<MbeanAttributeMap> queryMbeanAttributes()
+            throws IOException,
+                    InstanceNotFoundException,
+                    IntrospectionException,
+                    ReflectionException {
+        if (!isConnected()) {
+            connect();
+        }
+        List<MbeanAttributeMap> attributeMap = new ArrayList<MbeanAttributeMap>();
+        // null,null returns all Mbeans
+        Set<ObjectInstance> beans = rjmxConnection.getMBeanServer().queryMBeans(null, null);
+        for (ObjectInstance bean : beans) {
+            List<MBeanAttribute> attrs = new ArrayList<>();
+            MBeanInfo info = rjmxConnection.getMBeanServer().getMBeanInfo(bean.getObjectName());
+            for (MBeanAttributeInfo a : info.getAttributes()) {
+                attrs.add(
+                        new MBeanAttribute(
+                                a.getName(),
+                                a.getType(),
+                                a.getDescription(),
+                                bean.getClassName(),
+                                a.isReadable(),
+                                a.isWritable()));
+            }
+            attributeMap.add(new MbeanAttributeMap(bean.getClassName(), attrs));
+        }
+        return attributeMap;
+    }
 }

libcryostat/src/main/java/io/cryostat/libcryostat/net/MbeanAttributeMap.java

@@ -0,0 +1,130 @@
+/*
+ * Copyright The Cryostat Authors.
+ *
+ * Licensed 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
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * 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 io.cryostat.libcryostat.net;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+public class MbeanAttributeMap {
+
+    private String mBeanName;
+    private List<MBeanAttribute> attributes;
+
+    public MbeanAttributeMap(String name, List<MBeanAttribute> attrs) {
+        this.mBeanName = name;
+        this.attributes = new ArrayList<MBeanAttribute>(attrs);
+    }
+
+    // Default Constructor for ObjectMapper deserialization
+    public MbeanAttributeMap() {
+        this("", Collections.emptyList());
+    }
+
+    public String getMbeanName() {
+        return mBeanName;
+    }
+
+    public List<MBeanAttribute> getAttributes() {
+        return Collections.unmodifiableList(attributes);
+    }
+
+    public void setMbeanName(String mbeanName) {
+        this.mBeanName = mbeanName;
+    }
+
+    public void setAttributes(List<MBeanAttribute> attributes) {
+        this.attributes = new ArrayList<MBeanAttribute>(attributes);
+    }
+
+    public static class MBeanAttribute {
+
+        private String name;
+        private String type;
+        private String description;
+        private String parentBean;
+        private boolean isReadable;
+        private boolean isWritable;
+
+        public MBeanAttribute(
+                String name,
+                String type,
+                String description,
+                String parentBean,
+                boolean isReadable,
+                boolean isWritable) {
+            this.name = name;
+            this.type = type;
+            this.description = description;
+            this.parentBean = parentBean;
+            this.isReadable = isReadable;
+            this.isWritable = isWritable;
+        }
+
+        // Default constructor for ObjectMapper deserialization
+        public MBeanAttribute() {
+            this("", "", "", "", false, false);
+        }
+
+        public String getName() {
+            return name;
+        }
+
+        public void setName(String name) {
+            this.name = name;
+        }
+
+        public String getType() {
+            return type;
+        }
+
+        public void setType(String type) {
+            this.type = type;
+        }
+
+        public String getDescription() {
+            return description;
+        }
+
+        public void setDescription(String description) {
+            this.description = description;
+        }
+
+        public String getParentBean() {
+            return parentBean;
+        }
+
+        public void setParentBean(String parentBean) {
+            this.parentBean = parentBean;
+        }
+
+        public boolean isReadable() {
+            return isReadable;
+        }
+
+        public void setIsReadable(boolean isReadable) {
+            this.isReadable = isReadable;
+        }
+
+        public boolean isWritable() {
+            return isWritable;
+        }
+
+        public void setIsWritable(boolean isWritable) {
+            this.isWritable = isWritable;
+        }
+    }
+}