gapic: Restructure Paths.java.

Use the visitor pattern to implement:
 • toNode() - Takes a path.Any, returns an unboxed Node type.
 • toAny() - Inverse of toNode.
 • parentOf() - Returns the parent node of the given node.
 • setParent() - Returns a copy of the node with the parent changed.
 • toString()

Long and verbose, but is explicit and does the job. Happy to try and replace portions with reflection magic - I just want something that works for now.

gapic/src/main/com/google/gapid/models/ApiState.java

@@ -76,7 +76,7 @@ public void onStateFollowed(Path.Any path) {
   @Override
   protected ListenableFuture<Node> doLoad(Path.Any path) {
     return Futures.transformAsync(client.get(path),
-        tree -> Futures.transform(client.get(Paths.any(tree.getStateTree().getRoot())),
+        tree -> Futures.transform(client.get(Paths.toAny(tree.getStateTree().getRoot())),
             val -> new RootNode(
                 tree.getStateTree().getRoot().getTree(), val.getStateTreeNode())));
   }
@@ -115,7 +115,7 @@ protected void fireLoadedEvent() {
 
   public ListenableFuture<Node> load(Node node) {
     return node.load(shell, () -> Futures.transformAsync(
-        client.get(Paths.any(node.getPath(Path.StateTreeNode.newBuilder()))),
+        client.get(Paths.toAny(node.getPath(Path.StateTreeNode.newBuilder()))),
         value -> Futures.transform(constants.loadConstants(value.getStateTreeNode()),
             ignore -> new NodeData(value.getStateTreeNode()))));
   }

gapic/src/main/com/google/gapid/models/AtomStream.java

@@ -16,7 +16,6 @@
 package com.google.gapid.models;
 
 import static com.google.gapid.proto.service.memory.Memory.PoolNames.Application_VALUE;
-import static com.google.gapid.util.Paths.any;
 import static com.google.gapid.util.Paths.commandTree;
 import static com.google.gapid.util.Paths.lastCommand;
 import static com.google.gapid.util.Paths.observationsAfter;
@@ -104,14 +103,14 @@ public void onContextSelected(FilteringContext ctx) {
   @Override
   protected ListenableFuture<Node> doLoad(Path.Any path) {
     return Futures.transformAsync(client.get(path),
-        tree -> Futures.transform(client.get(Paths.any(tree.getCommandTree().getRoot())),
+        tree -> Futures.transform(client.get(Paths.toAny(tree.getCommandTree().getRoot())),
             val -> new RootNode(
                 tree.getCommandTree().getRoot().getTree(), val.getCommandTreeNode())));
   }
 
   public ListenableFuture<Node> load(Node node) {
     return node.load(shell, () -> Futures.transformAsync(
-        client.get(any(node.getPath(Path.CommandTreeNode.newBuilder()))), v1 -> {
+        client.get(Paths.toAny(node.getPath(Path.CommandTreeNode.newBuilder()))), v1 -> {
           Service.CommandTreeNode data = v1.getCommandTreeNode();
           if (data.getGroup().isEmpty() && data.hasCommands()) {
             return Futures.transform(
@@ -122,7 +121,7 @@ public ListenableFuture<Node> load(Node node) {
   }
 
   public ListenableFuture<API.Command> loadCommand(Path.Command path) {
-    return Futures.transformAsync(client.get(any(path)), value ->
+    return Futures.transformAsync(client.get(Paths.toAny(path)), value ->
         Futures.transform(constants.loadConstants(value.getCommand()), ignore ->
             value.getCommand()));
   }

gapic/src/main/com/google/gapid/models/ConstantSets.java

@@ -34,7 +34,7 @@ public class ConstantSets {
 
   public ConstantSets(Client client) {
     this.cache = FutureCache.hardCache(
-        path -> Futures.transform(client.get(Paths.any(path)), Service.Value::getConstantSet),
+        path -> Futures.transform(client.get(Paths.toAny(path)), Service.Value::getConstantSet),
         result -> result.getConstantsCount() != 0);
   }
 

gapic/src/main/com/google/gapid/models/Devices.java

@@ -118,7 +118,7 @@ public void loadDevices() {
     rpcController.start().listen(Futures.transformAsync(client.getDevices(), paths -> {
       List<ListenableFuture<Service.Value>> results = Lists.newArrayList();
       for (Path.Device path : paths) {
-        results.add(client.get(Paths.any(path)));
+        results.add(client.get(Paths.toAny(path)));
       }
       return Futures.allAsList(results);
     }), new UiErrorCallback<List<Service.Value>, List<Device.Instance>, Void>(shell, LOG) {

gapic/src/main/com/google/gapid/models/Follower.java

@@ -25,7 +25,6 @@
 import com.google.common.util.concurrent.ListenableFuture;
 import com.google.gapid.proto.service.api.API;
 import com.google.gapid.proto.service.path.Path;
-import com.google.gapid.proto.service.path.Path.Any.PathCase;
 import com.google.gapid.rpc.Rpc;
 import com.google.gapid.rpc.RpcException;
 import com.google.gapid.rpc.UiCallback;
@@ -37,15 +36,13 @@
 import com.google.gapid.util.Flags.Flag;
 import com.google.gapid.util.ObjectStore;
 import com.google.gapid.util.Paths;
-
-import org.eclipse.swt.widgets.Shell;
-
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ExecutionException;
 import java.util.function.Consumer;
 import java.util.logging.Level;
 import java.util.logging.Logger;
+import org.eclipse.swt.widgets.Shell;
 
 /**
  * Model handling link following throughout the UI.
@@ -209,8 +206,7 @@ public void onFollow(Path.Any path) {
       case FIELD:
       case ARRAY_INDEX:
       case MAP_INDEX:
-        if (Paths.contains(path, n ->
-            n.getPathCase() == PathCase.STATE || n.getPathCase() == PathCase.GLOBAL_STATE)) {
+        if (Paths.contains(path, n -> n instanceof Path.State || n instanceof Path.GlobalState)) {
           listeners.fire().onStateFollowed(path);
         } else {
           LOG.log(WARNING, "Unknown follow path result: " + path);