feat(java): add ping + galaxy-browse CLI subcommands and galaxy command aliases

- D4: add 'ping' subcommand (MX_COMMAND_KIND_PING / PingCommand{message}),
  accepting --session-id and optional --message (default "ping"); prints the
  worker's echoed diagnostic message.
- D8-java: add 'galaxy-browse' subcommand over browse()/LazyBrowseNode.expand()
  and raw BrowseChildren paging for --parent. JSON node shape matches the
  cross-client surface (flattened object fields + hasChildrenHint + nested
  children array).
- D9-java: make galaxy-test-connection / galaxy-last-deploy the primary names,
  keeping galaxy-test / galaxy-deploy-time as deprecated picocli aliases.
- Tests for ping, galaxy-browse JSON hasChildrenHint key, and alias resolution.
- README updated for the new/renamed subcommands.

clients/java/README.md

@@ -115,17 +115,33 @@ try (GalaxyRepositoryClient galaxy = GalaxyRepositoryClient.connect(options)) {
 messages directly so callers can read all fields (including the nested
 `GalaxyAttribute` list) without an extra DTO layer.
 
-The CLI exposes matching subcommands: `galaxy-test`, `galaxy-deploy-time`,
-`galaxy-discover`, and `galaxy-watch`. They take the same `--endpoint`,
-`--api-key-env`, `--plaintext`, `--ca-file`, `--server-name-override`,
-`--timeout`, and `--json` options as the gateway commands.
+The CLI exposes matching subcommands: `galaxy-test-connection`,
+`galaxy-last-deploy`, `galaxy-discover`, `galaxy-browse`, and `galaxy-watch`.
+The short names `galaxy-test` and `galaxy-deploy-time` remain as deprecated
+aliases for `galaxy-test-connection` and `galaxy-last-deploy` so existing
+scripts keep working. They take the same `--endpoint`, `--api-key-env`,
+`--plaintext`, `--ca-file`, `--server-name-override`, `--timeout`, and `--json`
+options as the gateway commands.
 
 ```powershell
-gradle :zb-mom-ww-mxgateway-cli:run --args="galaxy-test --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
-gradle :zb-mom-ww-mxgateway-cli:run --args="galaxy-deploy-time --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="galaxy-test-connection --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="galaxy-last-deploy --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
 gradle :zb-mom-ww-mxgateway-cli:run --args="galaxy-discover --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
 ```
 
+`galaxy-browse` walks the hierarchy via `BrowseChildren`. Without `--parent` it
+returns the root nodes and eagerly expands `--depth` further levels; with
+`--parent <gobject-id>` it returns exactly one level of children for that
+parent. The filter flags (`--category-ids`, `--template-contains`,
+`--tag-name-glob`, `--alarm-bearing-only`, `--historized-only`,
+`--include-attributes`) match `galaxy-discover`. The `--json` node shape is the
+cross-client browse surface: the flattened object fields plus a
+`hasChildrenHint` flag and a nested `children` array.
+
+```powershell
+gradle :zb-mom-ww-mxgateway-cli:run --args="galaxy-browse --depth 1 --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --json"
+```
+
 ### Browsing lazily
 
 For UI trees or OPC UA bridges, use `browseChildrenRaw` to walk one level at a
@@ -239,6 +255,7 @@ Run the CLI through Gradle:
 ```powershell
 gradle :zb-mom-ww-mxgateway-cli:run --args="version --json"
 gradle :zb-mom-ww-mxgateway-cli:run --args="open-session --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --client-session-name java-cli --json"
+gradle :zb-mom-ww-mxgateway-cli:run --args="ping --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --message hello --json"
 gradle :zb-mom-ww-mxgateway-cli:run --args="register --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --client-name java-cli --json"
 gradle :zb-mom-ww-mxgateway-cli:run --args="add-item --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --server-handle 1 --item TestObject.TestInt --json"
 gradle :zb-mom-ww-mxgateway-cli:run --args="advise --endpoint localhost:5000 --api-key-env MXGATEWAY_API_KEY --plaintext --session-id <id> --server-handle 1 --item-handle 1 --json"

clients/java/zb-mom-ww-mxgateway-cli/src/main/java/com/zb/mom/ww/mxgateway/cli/MxGatewayCli.java

@@ -1,7 +1,9 @@
 package com.zb.mom.ww.mxgateway.cli;
 
+import com.zb.mom.ww.mxgateway.client.BrowseChildrenOptions;
 import com.zb.mom.ww.mxgateway.client.DeployEventStream;
 import com.zb.mom.ww.mxgateway.client.GalaxyRepositoryClient;
+import com.zb.mom.ww.mxgateway.client.LazyBrowseNode;
 import com.zb.mom.ww.mxgateway.client.MxEventStream;
 import com.zb.mom.ww.mxgateway.client.MxGatewayAlarmFeedSubscription;
 import com.zb.mom.ww.mxgateway.client.MxGatewayClient;
@@ -10,6 +12,8 @@ import com.zb.mom.ww.mxgateway.client.MxGatewayClientVersion;
 import com.zb.mom.ww.mxgateway.client.MxGatewaySecrets;
 import com.zb.mom.ww.mxgateway.client.MxGatewaySession;
 import com.zb.mom.ww.mxgateway.client.MxValues;
+import galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenReply;
+import galaxy_repository.v1.GalaxyRepositoryOuterClass.BrowseChildrenRequest;
 import galaxy_repository.v1.GalaxyRepositoryOuterClass.DeployEvent;
 import galaxy_repository.v1.GalaxyRepositoryOuterClass.GalaxyAttribute;
 import galaxy_repository.v1.GalaxyRepositoryOuterClass.GalaxyObject;
@@ -26,8 +30,10 @@ import java.time.Duration;
 import java.time.Instant;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.HashSet;
 import java.util.LinkedHashMap;
 import java.util.List;
+import java.util.Set;
 import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.ArrayBlockingQueue;
@@ -42,11 +48,14 @@ import mxaccess_gateway.v1.MxaccessGateway.AlarmFeedMessage;
 import mxaccess_gateway.v1.MxaccessGateway.BulkReadResult;
 import mxaccess_gateway.v1.MxaccessGateway.BulkWriteResult;
 import mxaccess_gateway.v1.MxaccessGateway.CloseSessionRequest;
+import mxaccess_gateway.v1.MxaccessGateway.MxCommand;
+import mxaccess_gateway.v1.MxaccessGateway.MxCommandKind;
 import mxaccess_gateway.v1.MxaccessGateway.MxCommandReply;
 import mxaccess_gateway.v1.MxaccessGateway.MxEvent;
 import mxaccess_gateway.v1.MxaccessGateway.MxValue;
 import mxaccess_gateway.v1.MxaccessGateway.OnAlarmTransitionEvent;
 import mxaccess_gateway.v1.MxaccessGateway.OpenSessionRequest;
+import mxaccess_gateway.v1.MxaccessGateway.PingCommand;
 import mxaccess_gateway.v1.MxaccessGateway.StreamAlarmsRequest;
 import mxaccess_gateway.v1.MxaccessGateway.SubscribeResult;
 import mxaccess_gateway.v1.MxaccessGateway.Write2BulkEntry;
@@ -126,6 +135,7 @@ public final class MxGatewayCli implements Callable<Integer> {
         commandLine.addSubcommand("version", new VersionCommand());
         commandLine.addSubcommand("open-session", new OpenSessionCommand(clientFactory));
         commandLine.addSubcommand("close-session", new CloseSessionCommand(clientFactory));
+        commandLine.addSubcommand("ping", new PingCommandLine(clientFactory));
         commandLine.addSubcommand("register", new RegisterCommand(clientFactory));
         commandLine.addSubcommand("add-item", new AddItemCommand(clientFactory));
         commandLine.addSubcommand("advise", new AdviseCommand(clientFactory));
@@ -142,9 +152,10 @@ public final class MxGatewayCli implements Callable<Integer> {
         commandLine.addSubcommand("stream-alarms", new StreamAlarmsCommand(clientFactory));
         commandLine.addSubcommand("acknowledge-alarm", new AcknowledgeAlarmCommand(clientFactory));
         commandLine.addSubcommand("smoke", new SmokeCommand(clientFactory));
-        commandLine.addSubcommand("galaxy-test", new GalaxyTestConnectionCommand());
-        commandLine.addSubcommand("galaxy-deploy-time", new GalaxyDeployTimeCommand());
+        commandLine.addSubcommand("galaxy-test-connection", new GalaxyTestConnectionCommand());
+        commandLine.addSubcommand("galaxy-last-deploy", new GalaxyDeployTimeCommand());
         commandLine.addSubcommand("galaxy-discover", new GalaxyDiscoverCommand());
+        commandLine.addSubcommand("galaxy-browse", new GalaxyBrowseCommand());
         commandLine.addSubcommand("galaxy-watch", new GalaxyWatchCommand());
         commandLine.addSubcommand("batch", new BatchCommand(clientFactory));
         return commandLine;
@@ -359,7 +370,10 @@ public final class MxGatewayCli implements Callable<Integer> {
         }
     }
 
-    @Command(name = "galaxy-test", description = "Calls GalaxyRepository.TestConnection.")
+    @Command(
+            name = "galaxy-test-connection",
+            aliases = {"galaxy-test"},
+            description = "Calls GalaxyRepository.TestConnection.")
     static final class GalaxyTestConnectionCommand extends GalaxyCommand {
         @Override
         public Integer call() {
@@ -368,7 +382,7 @@ public final class MxGatewayCli implements Callable<Integer> {
                 PrintWriter out = common.spec.commandLine().getOut();
                 if (json) {
                     Map<String, Object> output = new LinkedHashMap<>();
-                    output.put("command", "galaxy-test");
+                    output.put("command", "galaxy-test-connection");
                     output.put("options", common.redactedJsonMap());
                     output.put("ok", ok);
                     out.println(jsonObject(output));
@@ -380,7 +394,10 @@ public final class MxGatewayCli implements Callable<Integer> {
         }
     }
 
-    @Command(name = "galaxy-deploy-time", description = "Calls GalaxyRepository.GetLastDeployTime.")
+    @Command(
+            name = "galaxy-last-deploy",
+            aliases = {"galaxy-deploy-time"},
+            description = "Calls GalaxyRepository.GetLastDeployTime.")
     static final class GalaxyDeployTimeCommand extends GalaxyCommand {
         @Override
         public Integer call() {
@@ -389,7 +406,7 @@ public final class MxGatewayCli implements Callable<Integer> {
                 PrintWriter out = common.spec.commandLine().getOut();
                 if (json) {
                     Map<String, Object> output = new LinkedHashMap<>();
-                    output.put("command", "galaxy-deploy-time");
+                    output.put("command", "galaxy-last-deploy");
                     output.put("options", common.redactedJsonMap());
                     output.put("present", result.isPresent());
                     output.put("timeOfLastDeploy", result.map(Instant::toString).orElse(""));
@@ -429,6 +446,260 @@ public final class MxGatewayCli implements Callable<Integer> {
         }
     }
 
+    /**
+     * Page size used for the raw {@code BrowseChildren} paging loop driven by
+     * the {@code --parent} one-level path. Mirrors {@code BROWSE_CHILDREN_PAGE_SIZE}
+     * in the client library's lazy-browse helper and the other clients' CLI page
+     * size so paging behaviour is consistent across languages.
+     */
+    private static final int BROWSE_CHILDREN_CLI_PAGE_SIZE = 500;
+
+    @Command(
+            name = "galaxy-browse",
+            description = "Browses the Galaxy hierarchy via GalaxyRepository.BrowseChildren.")
+    static final class GalaxyBrowseCommand extends GalaxyCommand {
+        @Option(
+                names = "--parent",
+                defaultValue = "-1",
+                description = "Parent gobject id to browse one level of children for; omit to walk the roots.")
+        int parent;
+
+        @Option(
+                names = "--depth",
+                defaultValue = "0",
+                description = "When walking roots, eagerly expand this many further levels before printing.")
+        int depth;
+
+        @Option(names = "--category-ids", description = "Comma-separated category ids to include.")
+        String categoryIds;
+
+        @Option(names = "--template-contains", description = "Comma-separated template names each child's chain must contain.")
+        String templateContains;
+
+        @Option(names = "--tag-name-glob", description = "SQL-LIKE-style glob applied to tag_name.")
+        String tagNameGlob;
+
+        @Option(names = "--alarm-bearing-only", description = "Restrict to alarm-bearing objects.")
+        boolean alarmBearingOnly;
+
+        @Option(names = "--historized-only", description = "Restrict to objects with at least one historized attribute.")
+        boolean historizedOnly;
+
+        @Option(names = "--include-attributes", description = "Request attribute population on each returned object.")
+        boolean includeAttributes;
+
+        @Override
+        public Integer call() {
+            if (depth < 0) {
+                throw new IllegalArgumentException("--depth must be non-negative");
+            }
+            BrowseChildrenOptions options = buildOptions();
+            PrintWriter out = common.spec.commandLine().getOut();
+            PrintWriter err = common.spec.commandLine().getErr();
+            try (GalaxyRepositoryClient client = connect()) {
+                if (parent >= 0) {
+                    if (depth > 0) {
+                        err.println("warning: --depth is ignored when --parent is specified.");
+                    }
+                    List<BrowseChild> children = browseOneLevel(client, parent, options);
+                    if (json) {
+                        List<Map<String, Object>> nodes = new ArrayList<>(children.size());
+                        for (BrowseChild child : children) {
+                            nodes.add(browseNodeMap(child.object(), child.hasChildrenHint(), List.of()));
+                        }
+                        Map<String, Object> output = new LinkedHashMap<>();
+                        output.put("command", "galaxy-browse");
+                        output.put("options", common.redactedJsonMap());
+                        output.put("parentId", parent);
+                        output.put("nodes", nodes);
+                        out.println(jsonObject(output));
+                    } else {
+                        out.println(children.size());
+                        for (BrowseChild child : children) {
+                            printBrowseChild(out, child);
+                        }
+                    }
+                    return 0;
+                }
+
+                List<LazyBrowseNode> roots = client.browse(options);
+                for (LazyBrowseNode root : roots) {
+                    expandToDepth(root, depth);
+                }
+                if (json) {
+                    List<Map<String, Object>> nodes = new ArrayList<>(roots.size());
+                    for (LazyBrowseNode root : roots) {
+                        nodes.add(lazyNodeMap(root));
+                    }
+                    Map<String, Object> output = new LinkedHashMap<>();
+                    output.put("command", "galaxy-browse");
+                    output.put("options", common.redactedJsonMap());
+                    output.put("nodes", nodes);
+                    out.println(jsonObject(output));
+                } else {
+                    out.println(roots.size());
+                    for (LazyBrowseNode root : roots) {
+                        printLazyNode(out, root, 0);
+                    }
+                }
+            }
+            return 0;
+        }
+
+        private BrowseChildrenOptions buildOptions() {
+            return BrowseChildrenOptions.builder()
+                    .categoryIds(parseOptionalIntList(categoryIds))
+                    .templateChainContains(parseOptionalStringList(templateContains))
+                    .tagNameGlob(tagNameGlob == null ? "" : tagNameGlob)
+                    // Tri-state: only override the server default when the flag is present.
+                    .includeAttributes(includeAttributes ? Boolean.TRUE : null)
+                    .alarmBearingOnly(alarmBearingOnly)
+                    .historizedOnly(historizedOnly)
+                    .build();
+        }
+    }
+
+    /** One raw {@code BrowseChildren} child paired with its server-supplied has-children hint. */
+    private record BrowseChild(GalaxyObject object, boolean hasChildrenHint) {
+    }
+
+    /**
+     * Drives the raw {@code BrowseChildren} paging loop for a single parent and
+     * returns the flattened one-level child list. Used by the {@code --parent}
+     * path, which surfaces a single level rather than the lazy root-tree walk.
+     */
+    private static List<BrowseChild> browseOneLevel(
+            GalaxyRepositoryClient client, int parentGobjectId, BrowseChildrenOptions options) {
+        List<BrowseChild> children = new ArrayList<>();
+        Set<String> seenPageTokens = new HashSet<>();
+        String pageToken = "";
+        while (true) {
+            BrowseChildrenRequest.Builder builder = BrowseChildrenRequest.newBuilder()
+                    .setPageSize(BROWSE_CHILDREN_CLI_PAGE_SIZE)
+                    .setPageToken(pageToken)
+                    .setParentGobjectId(parentGobjectId)
+                    .setAlarmBearingOnly(options.isAlarmBearingOnly())
+                    .setHistorizedOnly(options.isHistorizedOnly());
+            if (!options.getCategoryIds().isEmpty()) {
+                builder.addAllCategoryIds(options.getCategoryIds());
+            }
+            if (!options.getTemplateChainContains().isEmpty()) {
+                builder.addAllTemplateChainContains(options.getTemplateChainContains());
+            }
+            if (!options.getTagNameGlob().isEmpty()) {
+                builder.setTagNameGlob(options.getTagNameGlob());
+            }
+            if (options.getIncludeAttributes() != null) {
+                builder.setIncludeAttributes(options.getIncludeAttributes());
+            }
+
+            BrowseChildrenReply reply = client.browseChildrenRaw(builder.build());
+            for (int i = 0; i < reply.getChildrenCount(); i++) {
+                boolean hint = i < reply.getChildHasChildrenCount() && reply.getChildHasChildren(i);
+                children.add(new BrowseChild(reply.getChildren(i), hint));
+            }
+
+            pageToken = reply.getNextPageToken();
+            if (pageToken == null || pageToken.isEmpty()) {
+                return children;
+            }
+            if (!seenPageTokens.add(pageToken)) {
+                throw new IllegalStateException(
+                        "galaxy browse children returned repeated page token: " + pageToken);
+            }
+        }
+    }
+
+    /**
+     * Recursively expands a {@link LazyBrowseNode} up to {@code depth} further
+     * levels. A {@code depth} of 0 leaves the node unexpanded so callers print
+     * only the requested level. Nodes the server reports as childless are not
+     * expanded.
+     */
+    private static void expandToDepth(LazyBrowseNode node, int depth) {
+        if (depth <= 0) {
+            return;
+        }
+        if (node.hasChildrenHint()) {
+            node.expand();
+        }
+        for (LazyBrowseNode child : node.getChildren()) {
+            expandToDepth(child, depth - 1);
+        }
+    }
+
+    /**
+     * Renders one {@link LazyBrowseNode} (and any already-expanded descendants)
+     * as a JSON map. Mirrors the {@code galaxy-discover} object shape with an
+     * added {@code hasChildrenHint} flag and a nested {@code children} array,
+     * matching the cross-client browse JSON surface.
+     */
+    private static Map<String, Object> lazyNodeMap(LazyBrowseNode node) {
+        List<Map<String, Object>> children = new ArrayList<>();
+        if (node.isExpanded()) {
+            for (LazyBrowseNode child : node.getChildren()) {
+                children.add(lazyNodeMap(child));
+            }
+        }
+        return browseNodeMap(node.getObject(), node.hasChildrenHint(), children);
+    }
+
+    /**
+     * Builds the per-node browse JSON map: the flattened Galaxy object fields,
+     * the {@code hasChildrenHint} flag, and a nested {@code children} array.
+     * The {@code hasChildrenHint} key is the cross-client standard (Rust /
+     * Python / .NET / Go all use the same key and node shape).
+     */
+    static Map<String, Object> browseNodeMap(
+            GalaxyObject object, boolean hasChildrenHint, List<Map<String, Object>> children) {
+        Map<String, Object> values = galaxyObjectMap(object);
+        values.put("hasChildrenHint", hasChildrenHint);
+        values.put("children", children);
+        return values;
+    }
+
+    private static void printLazyNode(PrintWriter out, LazyBrowseNode node, int level) {
+        GalaxyObject obj = node.getObject();
+        out.printf(
+                "%s%d\t%s\t%s\t(attrs=%d, hasChildrenHint=%b)%n",
+                "  ".repeat(level),
+                obj.getGobjectId(),
+                obj.getTagName(),
+                obj.getBrowseName(),
+                obj.getAttributesCount(),
+                node.hasChildrenHint());
+        if (node.isExpanded()) {
+            for (LazyBrowseNode child : node.getChildren()) {
+                printLazyNode(out, child, level + 1);
+            }
+        }
+    }
+
+    private static void printBrowseChild(PrintWriter out, BrowseChild child) {
+        GalaxyObject obj = child.object();
+        out.printf(
+                "%d\t%s\t%s\t(attrs=%d, hasChildrenHint=%b)%n",
+                obj.getGobjectId(),
+                obj.getTagName(),
+                obj.getBrowseName(),
+                obj.getAttributesCount(),
+                child.hasChildrenHint());
+    }
+
+    private static List<Integer> parseOptionalIntList(String value) {
+        if (value == null || value.isBlank()) {
+            return List.of();
+        }
+        return parseIntList(value);
+    }
+
+    private static List<String> parseOptionalStringList(String value) {
+        if (value == null || value.isBlank()) {
+            return List.of();
+        }
+        return parseStringList(value);
+    }
+
     @Command(
             name = "galaxy-watch",
             description = "Streams GalaxyRepository.WatchDeployEvents until cancelled.")
@@ -622,6 +893,31 @@ public final class MxGatewayCli implements Callable<Integer> {
         }
     }
 
+    @Command(name = "ping", description = "Sends a diagnostic ping command to the session worker.")
+    static final class PingCommandLine extends GatewayCommand {
+        @Option(names = "--session-id", required = true, description = "Gateway session id.")
+        String sessionId;
+
+        @Option(names = "--message", defaultValue = "ping", description = "Message echoed back in the reply.")
+        String message;
+
+        PingCommandLine(MxGatewayCliClientFactory clientFactory) {
+            super(clientFactory);
+        }
+
+        @Override
+        public Integer call() {
+            try (MxGatewayCliClient client = clientFactory.connect(common.resolved())) {
+                MxCommandReply reply = client.session(sessionId).pingRaw(message);
+                // The worker echoes the message in the diagnostic message field;
+                // there is no dedicated ping reply payload, so the plain-text path
+                // surfaces that field.
+                writeOutput("ping", common, json, reply, reply::getDiagnosticMessage);
+            }
+            return 0;
+        }
+    }
+
     @Command(name = "register", description = "Invokes MXAccess Register.")
     static final class RegisterCommand extends GatewayCommand {
         @Option(names = "--session-id", required = true, description = "Gateway session id.")
@@ -1438,6 +1734,8 @@ public final class MxGatewayCli implements Callable<Integer> {
     }
 
     interface MxGatewayCliSession {
+        MxCommandReply pingRaw(String message);
+
         int register(String clientName);
 
         MxCommandReply registerRaw(String clientName);
@@ -1523,6 +1821,14 @@ public final class MxGatewayCli implements Callable<Integer> {
     }
 
     record GrpcMxGatewayCliSession(MxGatewaySession session) implements MxGatewayCliSession {
+        @Override
+        public MxCommandReply pingRaw(String message) {
+            return session.invokeCommand(MxCommand.newBuilder()
+                    .setKind(MxCommandKind.MX_COMMAND_KIND_PING)
+                    .setPing(PingCommand.newBuilder().setMessage(message))
+                    .build());
+        }
+
         @Override
         public int register(String clientName) {
             return session.register(clientName);

clients/java/zb-mom-ww-mxgateway-cli/src/test/java/com/zb/mom/ww/mxgateway/cli/MxGatewayCliTests.java

@@ -6,6 +6,7 @@ import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import com.zb.mom.ww.mxgateway.client.MxGatewayAlarmFeedSubscription;
 import com.zb.mom.ww.mxgateway.client.MxGatewayClientOptions;
+import galaxy_repository.v1.GalaxyRepositoryOuterClass.GalaxyObject;
 import io.grpc.stub.StreamObserver;
 import java.io.ByteArrayInputStream;
 import java.io.InputStream;
@@ -15,6 +16,7 @@ import java.nio.charset.StandardCharsets;
 import java.time.Duration;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
 import mxaccess_gateway.v1.MxaccessGateway.AcknowledgeAlarmReply;
 import mxaccess_gateway.v1.MxaccessGateway.AcknowledgeAlarmRequest;
 import mxaccess_gateway.v1.MxaccessGateway.ActiveAlarmSnapshot;
@@ -124,6 +126,119 @@ final class MxGatewayCliTests {
         assertTrue(run.output().contains("\"itemHandle\":7"));
     }
 
+    // ---- ping subcommand (D4) ----
+
+    @Test
+    void pingCommandForwardsMessageAndPrintsEcho() {
+        FakeClientFactory factory = new FakeClientFactory();
+        CliRun run = execute(
+                factory, "ping", "--session-id", "session-cli", "--message", "hello-mxgw");
+
+        assertEquals(0, run.exitCode());
+        assertEquals("hello-mxgw", factory.client.session.lastPingMessage);
+        // The worker echoes the message in the diagnostic message field; the
+        // plain-text path surfaces exactly that echoed value.
+        assertEquals("hello-mxgw", run.output().trim());
+    }
+
+    @Test
+    void pingCommandDefaultsMessageToPing() {
+        FakeClientFactory factory = new FakeClientFactory();
+        CliRun run = execute(factory, "ping", "--session-id", "session-cli");
+
+        assertEquals(0, run.exitCode());
+        assertEquals("ping", factory.client.session.lastPingMessage);
+    }
+
+    @Test
+    void pingCommandJsonIncludesPingKindAndDiagnosticMessage() {
+        FakeClientFactory factory = new FakeClientFactory();
+        CliRun run = execute(
+                factory, "ping", "--session-id", "session-cli", "--message", "diag-1", "--json");
+
+        assertEquals(0, run.exitCode());
+        String out = run.output();
+        assertTrue(out.contains("\"command\":\"ping\""), out);
+        assertTrue(out.contains("\"kind\":\"MX_COMMAND_KIND_PING\""), out);
+        assertTrue(out.contains("diag-1"), out);
+    }
+
+    // ---- galaxy-browse subcommand (D8-java) ----
+
+    @Test
+    void galaxyBrowseNodeJsonUsesHasChildrenHintKeyAndFlattensObjectFields() {
+        GalaxyObject object = GalaxyObject.newBuilder()
+                .setGobjectId(101)
+                .setTagName("Area001")
+                .setBrowseName("Area001")
+                .build();
+        Map<String, Object> leaf = MxGatewayCli.browseNodeMap(
+                GalaxyObject.newBuilder().setGobjectId(202).setTagName("Pump001").build(),
+                false,
+                List.of());
+        Map<String, Object> node = MxGatewayCli.browseNodeMap(object, true, List.of(leaf));
+
+        // Cross-client JSON parity: the per-node "has children" flag MUST use the
+        // key hasChildrenHint (Rust / Python / .NET / Go all standardized on it).
+        assertTrue(node.containsKey("hasChildrenHint"), node.toString());
+        assertEquals(Boolean.TRUE, node.get("hasChildrenHint"));
+        // Object fields are flattened directly into the node (matching the
+        // galaxy-discover object shape), not nested under an "object" key.
+        assertFalse(node.containsKey("object"), node.toString());
+        assertEquals(101L, ((Number) node.get("gobjectId")).longValue());
+        assertEquals("Area001", node.get("tagName"));
+        // Nested children array carries the same node shape recursively.
+        @SuppressWarnings("unchecked")
+        List<Map<String, Object>> children = (List<Map<String, Object>>) node.get("children");
+        assertEquals(1, children.size());
+        assertTrue(children.get(0).containsKey("hasChildrenHint"));
+        assertEquals(Boolean.FALSE, children.get(0).get("hasChildrenHint"));
+    }
+
+    @Test
+    void galaxyBrowseInvocationsParseCleanly() {
+        // galaxy-browse connects via GalaxyRepositoryClient.connect (a static),
+        // so the full surface is exercised only by the cross-language matrix
+        // against a live gateway. Here we assert the option surface parses.
+        assertReadmeExampleParses(new String[] {"galaxy-browse", "--json"});
+        assertReadmeExampleParses(new String[] {"galaxy-browse", "--parent", "42", "--json"});
+        assertReadmeExampleParses(new String[] {
+            "galaxy-browse",
+            "--depth", "2",
+            "--category-ids", "1,2",
+            "--template-contains", "$Pump",
+            "--tag-name-glob", "Area%",
+            "--alarm-bearing-only",
+            "--historized-only",
+            "--include-attributes",
+            "--json"
+        });
+    }
+
+    // ---- galaxy command-name aliases (D9-java) ----
+
+    @Test
+    void galaxyTestConnectionCanonicalAndDeprecatedAliasResolve() {
+        picocli.CommandLine commandLine = MxGatewayCli.commandLine(new FakeClientFactory());
+        // Both the canonical dash-separated name and the deprecated short alias
+        // must resolve to the same subcommand so existing scripts keep working.
+        assertTrue(commandLine.getSubcommands().containsKey("galaxy-test-connection"));
+        assertTrue(commandLine.getSubcommands().containsKey("galaxy-test"));
+        assertEquals(
+                commandLine.getSubcommands().get("galaxy-test-connection"),
+                commandLine.getSubcommands().get("galaxy-test"));
+    }
+
+    @Test
+    void galaxyLastDeployCanonicalAndDeprecatedAliasResolve() {
+        picocli.CommandLine commandLine = MxGatewayCli.commandLine(new FakeClientFactory());
+        assertTrue(commandLine.getSubcommands().containsKey("galaxy-last-deploy"));
+        assertTrue(commandLine.getSubcommands().containsKey("galaxy-deploy-time"));
+        assertEquals(
+                commandLine.getSubcommands().get("galaxy-last-deploy"),
+                commandLine.getSubcommands().get("galaxy-deploy-time"));
+    }
+
     @Test
     void subscribeBulkCommandPrintsResults() {
         CliRun run = execute(
@@ -652,6 +767,19 @@ final class MxGatewayCliTests {
         private boolean addItemCalled;
         private boolean adviseCalled;
         private MxValue lastWriteValue;
+        private String lastPingMessage;
+
+        @Override
+        public MxCommandReply pingRaw(String message) {
+            lastPingMessage = message;
+            // The worker echoes the request message in the diagnostic message
+            // field; there is no dedicated ping reply payload.
+            return MxCommandReply.newBuilder()
+                    .setKind(MxCommandKind.MX_COMMAND_KIND_PING)
+                    .setProtocolStatus(ok())
+                    .setDiagnosticMessage(message)
+                    .build();
+        }
 
         @Override
         public int register(String clientName) {