fix: resolve node for Java smoke host

References sdk-smoke Java failure in run 28129531025.

Author: james

java/src/test/java/com/jestevery/codebridge/ProtocolHostProcess.java

@@ -5,8 +5,11 @@
 import java.io.IOException;
 import java.io.InputStreamReader;
 import java.util.ArrayList;
+import java.util.LinkedHashSet;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
+import java.util.Set;
 import java.util.concurrent.TimeUnit;
 
 import com.google.gson.Gson;
@@ -19,10 +22,10 @@ class ProtocolHostProcess implements AutoCloseable {
 
     ProtocolHostProcess(int port, boolean autoPong, boolean sendControl, boolean dropPong) throws IOException, InterruptedException {
         File script = new File("src/test/resources/ProtocolHost.js");
-        String node = "/usr/local/bin/node";
-        ProcessBuilder pb = new ProcessBuilder(node, script.getAbsolutePath());
+        ProcessBuilder pb = new ProcessBuilder();
         Map<String, String> env = pb.environment();
-        env.put("PATH", System.getenv("PATH"));
+        String node = resolveNodeCommand(env);
+        pb.command(node, script.getAbsolutePath());
         env.put("PORT", Integer.toString(port));
         env.put("SECRET", "dev-secret");
         env.put("AUTO_PONG", autoPong ? "true" : "false");
@@ -50,6 +53,79 @@ class ProtocolHostProcess implements AutoCloseable {
         }
     }
 
+    private static String resolveNodeCommand(Map<String, String> env) throws IOException {
+        // CODE_BRIDGE_NODE may point at a specific node binary for environments
+        // where the Java test process does not inherit the expected PATH.
+        String override = trimToNull(env.get("CODE_BRIDGE_NODE"));
+        if (override != null) {
+            if (isPathLike(override)) {
+                File file = new File(override);
+                if (file.isFile() && file.canExecute()) {
+                    return file.getAbsolutePath();
+                }
+                throw new IOException("CODE_BRIDGE_NODE must point to an executable node binary: " + override);
+            }
+
+            String resolved = findExecutableOnPath(override, env.get("PATH"));
+            if (resolved != null) {
+                return resolved;
+            }
+            throw new IOException("CODE_BRIDGE_NODE was set but not found on PATH: " + override);
+        }
+
+        String resolved = findExecutableOnPath("node", env.get("PATH"));
+        if (resolved != null) {
+            return resolved;
+        }
+        throw new IOException("node executable not found on PATH; set CODE_BRIDGE_NODE to the node binary for Java protocol tests");
+    }
+
+    private static String findExecutableOnPath(String command, String path) {
+        if (trimToNull(path) == null) {
+            return null;
+        }
+
+        for (String dir : path.split(File.pathSeparator)) {
+            if (dir.isBlank()) {
+                continue;
+            }
+            for (String candidate : executableCandidates(command)) {
+                File file = new File(dir, candidate);
+                if (file.isFile() && file.canExecute()) {
+                    return file.getAbsolutePath();
+                }
+            }
+        }
+        return null;
+    }
+
+    private static Set<String> executableCandidates(String command) {
+        Set<String> candidates = new LinkedHashSet<>();
+        candidates.add(command);
+
+        String pathExt = System.getenv("PATHEXT");
+        if (pathExt != null) {
+            for (String extension : pathExt.split(File.pathSeparator)) {
+                if (!extension.isBlank()
+                        && !command.toLowerCase(Locale.ROOT).endsWith(extension.toLowerCase(Locale.ROOT))) {
+                    candidates.add(command + extension);
+                }
+            }
+        }
+        return candidates;
+    }
+
+    private static boolean isPathLike(String command) {
+        return new File(command).isAbsolute() || command.contains("/") || command.contains("\\");
+    }
+
+    private static String trimToNull(String value) {
+        if (value == null || value.trim().isEmpty()) {
+            return null;
+        }
+        return value.trim();
+    }
+
     List<Map<String, Object>> readEvents(long timeoutMs) throws IOException {
         long deadline = System.currentTimeMillis() + timeoutMs;
         List<Map<String, Object>> events = new ArrayList<>();