Add 'forks' config into xml config (#2568)

* Add forks into xml config.

* Add forks into xml config.

* Add forks into xml config.

Author: carryxyh

dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/AbstractMethodConfig.java

@@ -64,6 +64,19 @@ public abstract class AbstractMethodConfig extends AbstractConfig {
     // customized parameters
     protected Map<String, String> parameters;
 
+    /**
+     * forks for forking cluster
+     */
+    protected Integer forks;
+
+    public Integer getForks() {
+        return forks;
+    }
+
+    public void setForks(Integer forks) {
+        this.forks = forks;
+    }
+
     public Integer getTimeout() {
         return timeout;
     }

dubbo-config/dubbo-config-api/src/test/java/org/apache/dubbo/config/AbstractMethodConfigTest.java

@@ -35,6 +35,13 @@ public void testTimeout() throws Exception {
         assertThat(methodConfig.getTimeout(), equalTo(10));
     }
 
+    @Test
+    public void testForks() throws Exception {
+        MethodConfig methodConfig = new MethodConfig();
+        methodConfig.setForks(10);
+        assertThat(methodConfig.getForks(), equalTo(10));
+    }
+
     @Test
     public void testRetries() throws Exception {
         MethodConfig methodConfig = new MethodConfig();

dubbo-config/dubbo-config-spring/src/main/resources/META-INF/compat/dubbo.xsd

@@ -101,6 +101,11 @@
                         <xsd:documentation><![CDATA[ Use cluster strategy. ]]></xsd:documentation>
                     </xsd:annotation>
                 </xsd:attribute>
+                <xsd:attribute name="forks" type="xsd:string">
+                    <xsd:annotation>
+                        <xsd:documentation><![CDATA[ ForkingCluster forks. ]]></xsd:documentation>
+                    </xsd:annotation>
+                </xsd:attribute>
                 <xsd:attribute name="filter" type="xsd:string">
                     <xsd:annotation>
                         <xsd:documentation><![CDATA[ The filter. ]]></xsd:documentation>
@@ -492,6 +497,11 @@
                 <xsd:documentation><![CDATA[ The registry cluster type. ]]></xsd:documentation>
             </xsd:annotation>
         </xsd:attribute>
+        <xsd:attribute name="forks" type="xsd:string">
+            <xsd:annotation>
+                <xsd:documentation><![CDATA[ ForkingCluster forks. ]]></xsd:documentation>
+            </xsd:annotation>
+        </xsd:attribute>
         <xsd:attribute name="group" type="xsd:string">
             <xsd:annotation>
                 <xsd:documentation><![CDATA[ The registry group. ]]></xsd:documentation>

dubbo-config/dubbo-config-spring/src/main/resources/META-INF/dubbo.xsd

@@ -101,6 +101,11 @@
                         <xsd:documentation><![CDATA[ Use cluster strategy. ]]></xsd:documentation>
                     </xsd:annotation>
                 </xsd:attribute>
+                <xsd:attribute name="forks" type="xsd:string">
+                    <xsd:annotation>
+                        <xsd:documentation><![CDATA[ ForkingCluster forks. ]]></xsd:documentation>
+                    </xsd:annotation>
+                </xsd:attribute>
                 <xsd:attribute name="filter" type="xsd:string">
                     <xsd:annotation>
                         <xsd:documentation><![CDATA[ The filter. ]]></xsd:documentation>
@@ -486,6 +491,11 @@
                 <xsd:documentation><![CDATA[ The registry cluster type. ]]></xsd:documentation>
             </xsd:annotation>
         </xsd:attribute>
+        <xsd:attribute name="forks" type="xsd:string">
+            <xsd:annotation>
+                <xsd:documentation><![CDATA[ ForkingCluster forks. ]]></xsd:documentation>
+            </xsd:annotation>
+        </xsd:attribute>
         <xsd:attribute name="group" type="xsd:string">
             <xsd:annotation>
                 <xsd:documentation><![CDATA[ The registry group. ]]></xsd:documentation>

dubbo-config/dubbo-config-spring/src/test/java/org/apache/dubbo/config/spring/ConfigTest.java

@@ -147,6 +147,20 @@ public void testToString() {
         assertTrue(str.endsWith(" />"));
     }
 
+    @Test
+    public void testForks() {
+        ReferenceConfig<DemoService> reference = new ReferenceConfig<DemoService>();
+        reference.setApplication(new ApplicationConfig("consumer"));
+        reference.setRegistry(new RegistryConfig(RegistryConfig.NO_AVAILABLE));
+        reference.setInterface(DemoService.class);
+        reference.setUrl("dubbo://127.0.0.1:20881");
+
+        int forks = 10;
+        reference.setForks(forks);
+        String str = reference.toString();
+        assertTrue(str.contains("forks=\"" + forks + "\""));
+    }
+
     @Test
     public void testMultiProtocol() {
         ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext(ConfigTest.class.getPackage().getName().replace('.', '/') + "/multi-protocol.xml");