Feat cross app wf + use Java 11, not Java 8

CONTRIBUTING.md

@@ -1,3 +1,8 @@
+Verify Compilation:
+```shell
+./gradlew compileJava
+```
+
 Build & test:
 
 ```shell

client/src/main/java/io/dapr/durabletask/TaskOptions.java

@@ -8,26 +8,51 @@
 public final class TaskOptions {
     private final RetryPolicy retryPolicy;
     private final RetryHandler retryHandler;
+    private final String appID;
+
+    public TaskOptions(RetryPolicy retryPolicy, RetryHandler retryHandler, String appID) {
+        this.retryPolicy = retryPolicy;
+        this.retryHandler = retryHandler;
+        this.appID = appID;
+    }
 
     public TaskOptions(RetryPolicy retryPolicy, RetryHandler retryHandler) {
         this.retryPolicy = retryPolicy;
         this.retryHandler = retryHandler;
+        this.appID = null;
     }
 
     /**
      * Creates a new {@code TaskOptions} object from a {@link RetryPolicy}.
      * @param retryPolicy the retry policy to use in the new {@code TaskOptions} object.
      */
     public TaskOptions(RetryPolicy retryPolicy) {
-        this(retryPolicy, null);
+        this(retryPolicy, null, null);
     }
 
     /**
      * Creates a new {@code TaskOptions} object from a {@link RetryHandler}.
      * @param retryHandler the retry handler to use in the new {@code TaskOptions} object.
      */
     public TaskOptions(RetryHandler retryHandler) {
-        this(null, retryHandler);
+        this(null, retryHandler, null);
+    }
+
+    /**
+     * Creates a new {@code TaskOptions} object with the specified app ID.
+     * @param appID the app ID to use for cross-app workflow routing
+     */
+    public TaskOptions(String appID) {
+        this(null, null, appID);
+    }
+
+    /**
+     * Creates a new {@code TaskOptions} object with the specified retry policy and app ID.
+     * @param retryPolicy the retry policy to use
+     * @param appID the app ID to use for cross-app workflow routing
+     */
+    public TaskOptions(RetryPolicy retryPolicy, String appID) {
+        this(retryPolicy, null, appID);
     }
 
     boolean hasRetryPolicy() {
@@ -53,4 +78,16 @@ boolean hasRetryHandler() {
     public RetryHandler getRetryHandler() {
         return this.retryHandler;
     }
+
+    /**
+     * Gets the configured app ID value or {@code null} if none was configured.
+     * @return the configured app ID
+     */
+    public String getAppID() {
+        return this.appID;
+    }
+
+    boolean hasAppID() {
+        return this.appID != null && !this.appID.isEmpty();
+    }
 }

client/src/test/java/io/dapr/durabletask/TaskOptionsTest.java

@@ -0,0 +1,88 @@
+/*
+ * Copyright 2025 The Dapr 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.dapr.durabletask;
+
+import org.junit.jupiter.api.Test;
+import java.time.Duration;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * Unit tests for TaskOptions with cross-app workflow support.
+ */
+public class TaskOptionsTest {
+
+    @Test
+    void taskOptionsWithAppID() {
+        TaskOptions options = new TaskOptions("app1");
+
+        assertTrue(options.hasAppID());
+        assertEquals("app1", options.getAppID());
+        assertFalse(options.hasRetryPolicy());
+        assertFalse(options.hasRetryHandler());
+    }
+
+    @Test
+    void taskOptionsWithRetryPolicyAndAppID() {
+        RetryPolicy retryPolicy = new RetryPolicy(3, Duration.ofSeconds(1));
+        TaskOptions options = new TaskOptions(retryPolicy, null, "app2");
+
+        assertTrue(options.hasAppID());
+        assertEquals("app2", options.getAppID());
+        assertTrue(options.hasRetryPolicy());
+        assertEquals(retryPolicy, options.getRetryPolicy());
+        assertFalse(options.hasRetryHandler());
+    }
+
+    @Test
+    void taskOptionsWithRetryHandlerAndAppID() {
+        RetryHandler retryHandler = new RetryHandler() {
+            @Override
+            public boolean handle(RetryContext context) {
+                return context.getLastAttemptNumber() < 2;
+            }
+        };
+        TaskOptions options = new TaskOptions(null, retryHandler, "app3");
+
+        assertTrue(options.hasAppID());
+        assertEquals("app3", options.getAppID());
+        assertFalse(options.hasRetryPolicy());
+        assertTrue(options.hasRetryHandler());
+        assertEquals(retryHandler, options.getRetryHandler());
+    }
+
+    @Test
+    void taskOptionsWithoutAppID() {
+        TaskOptions options = new TaskOptions(null, null, null);
+
+        assertFalse(options.hasAppID());
+        assertNull(options.getAppID());
+    }
+
+    @Test
+    void taskOptionsWithEmptyAppID() {
+        TaskOptions options = new TaskOptions("");
+
+        assertFalse(options.hasAppID());
+        assertEquals("", options.getAppID());
+    }
+
+    @Test
+    void taskOptionsWithNullAppID() {
+        TaskOptions options = new TaskOptions(null, null, null);
+
+        assertFalse(options.hasAppID());
+        assertNull(options.getAppID());
+    }
+}