1.show variable list in debug view (eclipse-jdtls#43)

* 1.add variable list

Signed-off-by: andxu <andxu@microsoft.com>

* 1.fix a constructor error: missing field assignment.

Signed-off-by: andxu <andxu@microsoft.com>

* ArrayUtils.toStringArray is not available in a low version, remove the usage.

Signed-off-by: andxu <andxu@microsoft.com>

* add javadoc back

Signed-off-by: andxu <andxu@microsoft.com>

* remove local debug code

Signed-off-by: andxu <andxu@microsoft.com>

* remove local debug code

Signed-off-by: andxu <andxu@microsoft.com>

* adjust class signature about util class

Signed-off-by: andxu <andxu@microsoft.com>

* change the options per request.

Signed-off-by: andxu <andxu@microsoft.com>

* change the options per request.

Signed-off-by: andxu <andxu@microsoft.com>

* 1. check all thread running to recycle all ids.
2. remove a unused method in variable formatter.

Signed-off-by: andxu <andxu@microsoft.com>

* 1. check all thread running to recycle all ids.
2. remove a unused method in variable formatter.

Signed-off-by: andxu <andxu@microsoft.com>

org.eclipse.jdt.ls.debug/src/org/eclipse/jdt/ls/debug/adapter/RecyclableObjectPool.java

@@ -0,0 +1,138 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Microsoft Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Microsoft Corporation - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.jdt.ls.debug.adapter;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+/**
+ * An utility object pool class with the following  ability: 
+ * 1. store an object to get an object id.
+ * 2. remove an object.
+ * 3. remove objects which has specified owner.
+ * 4. remove all objects.
+ *
+ * <p>It is thread-safe, the duplicate object will not be stored, an object can be referenced by multiple owners, it is
+ * removed only when user explicitly calls removeObjectById or all the owners has been removed.</p>
+ *
+ * @param <O> the owner class type
+ * @param <V> the object type
+ */
+public class RecyclableObjectPool<O, V> {
+    private final IdCollection<V> objectCollection = new IdCollection<>();
+    private final Map<V, Set<O>> referenceMap = new HashMap<>();
+    private final Map<V, Integer> objectIdMap = new HashMap<>();
+
+    /**
+     * Add an object into this pool, if the object is already added, the original id will be used, it will also create a 
+     * reference link from the object to its owner. 
+     * 
+     * @param owner the owner of this object
+     * @param object the object
+     * @return the inner id of this object
+     */
+    public int addObject(O owner, V object) {
+        if (owner == null) {
+            throw new IllegalArgumentException("Owner cannot be null.");
+        }
+        if (object == null) {
+            throw new IllegalArgumentException("Null object cannot be added.");
+        }
+        synchronized (this) {
+            if (!referenceMap.containsKey(object)) {
+                // the object is new
+                Set<O> owners = new HashSet<>(1);
+                owners.add(owner);
+                referenceMap.put(object, owners);
+                int id = objectCollection.create(object);
+                objectIdMap.put(object, id);
+                return id;
+            } else {
+                // the object is already in this pool
+                referenceMap.get(object).add(owner);
+                return objectIdMap.get(object);
+            }
+        }
+    }
+
+    /**
+     * Get the object by object id.
+     * 
+     * @param id the object id.
+     * @return the object, null if the object cannot be found.
+     */
+    public V getObjectById(int id) {
+        synchronized (this) {
+            return objectCollection.get(id);
+        }
+    }
+
+    /**
+     * Remove the object by object id.
+     * 
+     * @param id the object id.
+     * @return true if the object is removed successfully, false if the object cannot be found.
+     */
+    public boolean removeObjectById(int id) {
+        synchronized (this) {
+            V object = this.objectCollection.remove(id);
+            if (object == null)  {
+                return false;
+            }
+            referenceMap.remove(object);
+            objectIdMap.remove(object);
+            return true;
+        }
+    }
+
+    /**
+     * Remove a group of objects with the owner, the objects which only refers this owner will be removed.
+     *  
+     * @param owner the owner.
+     * @return true if any object is removed.
+     */
+    public boolean removeObjectsByOwner(O owner) {
+        if (owner == null) {
+            throw new IllegalArgumentException("owner cannot be null.");
+        }
+        synchronized (this) {
+            List<V> recycling = new ArrayList<>();
+            referenceMap.forEach((key, value) -> {
+                if (value.remove(owner)) {
+                    if (value.isEmpty()) {
+                        recycling.add(key);
+                    }
+                }
+            });
+            for (V recycled : recycling) {
+                this.objectCollection.remove(objectIdMap.remove(recycled));
+                referenceMap.remove(recycled);
+            }
+            return !recycling.isEmpty();
+        }
+    }
+
+    /**
+     * Removes all the objects.
+     */
+    public void removeAllObjects() {
+        synchronized (this) {
+            this.objectCollection.reset();
+            this.referenceMap.clear();
+            this.objectIdMap.clear();
+        }
+    }
+}

org.eclipse.jdt.ls.debug/src/org/eclipse/jdt/ls/debug/adapter/Requests.java

@@ -16,6 +16,10 @@
  */
 public class Requests {
 
+    public static class ValueFormat {
+        public boolean hex;
+    }
+
     public static class Arguments {
 
     }
@@ -117,13 +121,15 @@ public static class VariablesArguments extends Arguments {
         public int variablesReference = -1;
         public String filter;
         public int start;
-        public int count;
+        public int count;        
+        public ValueFormat format;
     }
 
     public static class SetVariableArguments extends Arguments {
         public int variablesReference;
         public String name;
         public String value;
+        public ValueFormat format;
     }
 
     public static class SourceArguments extends Arguments {
@@ -134,5 +140,6 @@ public static class EvaluateArguments extends Arguments {
         public String expression;
         public int frameId;
         public String context;
+        public ValueFormat format;
     }
 }

org.eclipse.jdt.ls.debug/src/org/eclipse/jdt/ls/debug/adapter/variables/IVariableFormatter.java

@@ -0,0 +1,63 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Microsoft Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Microsoft Corporation - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.jdt.ls.debug.adapter.variables;
+
+import com.sun.jdi.Type;
+import com.sun.jdi.Value;
+import org.eclipse.jdt.ls.debug.adapter.formatter.ITypeFormatter;
+import org.eclipse.jdt.ls.debug.adapter.formatter.IValueFormatter;
+
+import java.util.Map;
+
+public interface IVariableFormatter {
+    /**
+     * Register a type formatter. Be careful about the priority of formatters, the formatter with the largest
+     * priority which accepts the type will be used.
+     *
+     * @param typeFormatter the type formatter
+     * @param priority      the priority for this formatter
+     */
+    void registerTypeFormatter(ITypeFormatter typeFormatter, int priority);
+
+    /**
+     * Register a value formatter. Be careful about the priority of formatters, the formatter with the largest
+     * priority which accepts the type will be used.
+     *
+     * @param formatter the value formatter
+     * @param priority  the priority for this formatter
+     */
+    void registerValueFormatter(IValueFormatter formatter, int priority);
+
+    /**
+     * Get the default options for all formatters registered.
+     * @return The default options.
+     */
+    Map<String, Object> getDefaultOptions();
+
+    /**
+     * Get display text of the value.
+     *
+     * @param value   the value.
+     * @param options additional information about expected format
+     * @return the display text of the value
+     */
+    String valueToString(Value value, Map<String, Object> options);
+
+    /**
+     * Get display name of type.
+     *
+     * @param type    the JDI type
+     * @param options additional information about expected format
+     * @return display name of type of the value.
+     */
+    String typeToString(Type type, Map<String, Object> options);
+}

org.eclipse.jdt.ls.debug/src/org/eclipse/jdt/ls/debug/adapter/variables/StackFrameScope.java

@@ -0,0 +1,63 @@
+/*******************************************************************************
+* Copyright (c) 2017 Microsoft Corporation and others.
+* All rights reserved. This program and the accompanying materials
+* are made available under the terms of the Eclipse Public License v1.0
+* which accompanies this distribution, and is available at
+* http://www.eclipse.org/legal/epl-v10.html
+*
+* Contributors:
+*     Microsoft Corporation - initial API and implementation
+*******************************************************************************/
+
+package org.eclipse.jdt.ls.debug.adapter.variables;
+
+import java.util.Objects;
+
+import com.sun.jdi.StackFrame;
+
+public class StackFrameScope {
+    private final StackFrame stackFrame;
+    private final String scope;
+    private int hashCode;
+
+
+    /**
+     * Create a stack frame scope with the related stack frame.
+     * 
+     * @param stackFrame the JDI stack frame
+     * @param scope the scope
+     */
+    public StackFrameScope(StackFrame stackFrame, String scope) {
+        this.stackFrame = stackFrame;
+        this.scope = scope;
+        this.hashCode = this.getStackFrame().hashCode() & this.getScope().hashCode();
+
+    }
+
+    @Override
+    public String toString() {
+        return String.format("%s %s", String.valueOf(getStackFrame()), getScope());
+    }
+
+    @Override
+    public int hashCode() {
+        return hashCode;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (!(o instanceof StackFrameScope)) {
+            return false;
+        }
+        final StackFrameScope other = (StackFrameScope) o;
+        return (Objects.equals(this.getStackFrame(), other.getStackFrame()) && Objects.equals(this.getScope(), other.getScope()));
+    }
+
+    public StackFrame getStackFrame() {
+        return stackFrame;
+    }
+
+    public String getScope() {
+        return scope;
+    }
+}

org.eclipse.jdt.ls.debug/src/org/eclipse/jdt/ls/debug/adapter/variables/ThreadObjectReference.java

@@ -0,0 +1,69 @@
+/*******************************************************************************
+ * Copyright (c) 2017 Microsoft Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Microsoft Corporation - initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.jdt.ls.debug.adapter.variables;
+
+import java.util.Objects;
+
+import com.sun.jdi.ObjectReference;
+import com.sun.jdi.ThreadReference;
+
+public class ThreadObjectReference {
+    private final ThreadReference thread;
+    private final ObjectReference object;
+    private int hashCode;
+
+    /**
+     * Create a JDI object with the related thread.
+     * 
+     * @param thread the JDI thread
+     * @param object the object
+     */
+    public ThreadObjectReference(ThreadReference thread,
+                                 ObjectReference object) {
+        if (thread == null) {
+            throw new IllegalArgumentException("Null argument 'thread' is illegal.");
+        }
+        if (object == null) {
+            throw new IllegalArgumentException("Parameter 'object' is null.");
+        }
+        this.thread = thread;
+        this.object = object;
+        hashCode = this.object.hashCode() & this.thread.hashCode();
+    }
+
+    @Override
+    public String toString() {
+        return this.object.toString();
+    }
+
+    @Override
+    public int hashCode() {
+        return hashCode;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (!(o instanceof ThreadObjectReference)) {
+            return false;
+        }
+        final ThreadObjectReference other = (ThreadObjectReference) o;
+        return (Objects.equals(this.thread, other.thread) && Objects.equals(this.object, other.object));
+    }
+
+    public ThreadReference getThread() {
+        return thread;
+    }
+
+    public ObjectReference getObject() {
+        return object;
+    }
+}