Update the latest code

CHANGES.md

@@ -6,10 +6,10 @@
 2. Asset transfer to ASF, includeing pom, license, DISCLAIMER and so on, #1491
 3. Introduce of new dispatcher policy: EagerThreadpool, #1568
 4. Separate monitor data with group and version, #1407
-5. Spring Boot Enhancenment, #1611
-6. Gaceful shutdown enhancement
+5. Spring Boot Enhancement, #1611
+6. Graceful shutdown enhancement
    - Remove exporter destroy logic in AnnotationBean.
    - Waiting for registry notification on consumer side by checking channel state.
 7. Simplify consumer/provider side check in RpcContext, #1444.
 
-Issues and Pull Requests, check [milestone-2.6.2](https://github.com/apache/incubator-dubbo/milestone/15).
+Issues and Pull Requests, check [milestone-2.6.2](https://github.com/apache/incubator-dubbo/milestone/15).

CONTRIBUTING.md

@@ -63,4 +63,14 @@ Thanks for contributing!
 ### Code style
 
 We provide a template file [dubbo_codestyle_for_idea.xml](https://github.com/apache/incubator-dubbo/tree/master/codestyle/dubbo_codestyle_for_idea.xml) for IntelliJ idea, you can import it to you IDE. 
-If you use Eclipse you can config manually by referencing the same file.
+If you use Eclipse you can config manually by referencing the same file.
+
+**NOTICE**
+
+It is very important to set the dubbo_codestyle_for_idea.xml, otherwise you will fail to pass the Travis CI. Steps to set the code style are as below:
+
+1. Enter `Editor > Code Style`
+2. To manage a code style scheme, in the Code Style page, select the desired scheme from the drop-down list, and click ![manage profiles](codestyle/manage_profiles.png).
+From the drop-down list, select `Import Scheme`, then select this option `IntelliJ IDEA code style XML` to import scheme
+3. In the Scheme field, type the name of the new scheme and press ⏎ to save the changes.
+

PULL_REQUEST_TEMPLATE.md

@@ -16,5 +16,5 @@ Follow this checklist to help us incorporate your contribution quickly and easil
 - [ ] Format the pull request title like `[Dubbo-XXX] Fix UnknownException when host config not exist #XXX`. Each commit in the pull request should have a meaningful subject line and body.
 - [ ] Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
 - [ ] Write necessary unit-test to verify your logic correction, more mock a little better when cross module dependency exist. If the new feature or significant change is committed, please remember to add integration-test in [test module](https://github.com/apache/incubator-dubbo/tree/master/dubbo-test).
-- [ ] Run `mvn clean install -DskipTests` & `mvn clean test-compile failsafe:integration-test` to make sure unit-test and integration-test pass.
+- [ ] Run `mvn clean install -DskipTests=false` & `mvn clean test-compile failsafe:integration-test` to make sure unit-test and integration-test pass.
 - [ ] If this contribution is large, please follow the [Software Donation Guide](https://github.com/apache/incubator-dubbo/wiki/Software-donation-guide).

README.md

@@ -147,7 +147,7 @@ The consumer will print out `Hello world` on the screen.
 
 * [Your first Dubbo application](http://dubbo.apache.org/en-us/blog/dubbo-101.html) - A 101 tutorial to reveal more details, with the same code above.
 * [Dubbo user manual](http://dubbo.apache.org/en-us/docs/user/preface/background.html) - How to use Dubbo and all its features.
-* [Dubbo developer guide](http://dubbo.apache.org/en-us/docs/dev/build.html) - How to invovle in Dubbo development.
+* [Dubbo developer guide](http://dubbo.apache.org/en-us/docs/dev/build.html) - How to involve in Dubbo development.
 * [Dubbo admin manual](http://dubbo.apache.org/en-us/docs/admin/install/provider-demo.html) - How to admin and manage Dubbo services.
 
 ## Contact

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/loadbalance/AbstractLoadBalance.java

@@ -26,10 +26,17 @@
 
 /**
  * AbstractLoadBalance
- *
  */
 public abstract class AbstractLoadBalance implements LoadBalance {
-
+    /**
+     * Calculate the weight according to the uptime proportion of warmup time
+     * the new weight will be within 1(inclusive) to weight(inclusive)
+     *
+     * @param uptime the uptime in milliseconds
+     * @param warmup the warmup time in milliseconds
+     * @param weight the weight of an invoker
+     * @return weight which takes warmup into account
+     */
     static int calculateWarmupWeight(int uptime, int warmup, int weight) {
         int ww = (int) ((float) uptime / ((float) warmup / (float) weight));
         return ww < 1 ? 1 : (ww > weight ? weight : ww);
@@ -48,6 +55,15 @@ public <T> Invoker<T> select(List<Invoker<T>> invokers, URL url, Invocation invo
 
     protected abstract <T> Invoker<T> doSelect(List<Invoker<T>> invokers, URL url, Invocation invocation);
 
+
+    /**
+     * Get the weight of the invoker's invocation which takes warmup time into account
+     * if the uptime is within the warmup time, the weight will be reduce proportionally
+     *
+     * @param invoker    the invoker
+     * @param invocation the invocation of this invoker
+     * @return weight
+     */
     protected int getWeight(Invoker<?> invoker, Invocation invocation) {
         int weight = invoker.getUrl().getMethodParameter(invocation.getMethodName(), Constants.WEIGHT_KEY, Constants.DEFAULT_WEIGHT);
         if (weight > 0) {
@@ -60,7 +76,7 @@ protected int getWeight(Invoker<?> invoker, Invocation invocation) {
                 }
             }
         }
-        return weight;
+        return weight >= 0 ? weight : 0;
     }
 
 }

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/loadbalance/LeastActiveLoadBalance.java

@@ -46,20 +46,25 @@ protected <T> Invoker<T> doSelect(List<Invoker<T>> invokers, URL url, Invocation
         int leastCount = 0;
         // The index of invokers having the same least active value (leastActive)
         int[] leastIndexes = new int[length];
+        // the weight of every invokers
+        int[] weights = new int[length];
         // The sum of the warmup weights of all the least active invokes
         int totalWeight = 0;
         // The weight of the first least active invoke
         int firstWeight = 0;
         // Every least active invoker has the same weight value?
         boolean sameWeight = true;
 
+
         // Filter out all the least active invokers
         for (int i = 0; i < length; i++) {
             Invoker<T> invoker = invokers.get(i);
             // Get the active number of the invoke
             int active = RpcStatus.getStatus(invoker.getUrl(), invocation.getMethodName()).getActive();
             // Get the weight of the invoke configuration. The default value is 100.
             int afterWarmup = getWeight(invoker, invocation);
+            // save for later use
+            weights[i] = afterWarmup;
             // If it is the first invoker or the active number of the invoker is less than the current least active number
             if (leastActive == -1 || active < leastActive) {
                 // Reset the active number of the current invoker to the least active number
@@ -95,12 +100,12 @@ protected <T> Invoker<T> doSelect(List<Invoker<T>> invokers, URL url, Invocation
         if (!sameWeight && totalWeight > 0) {
             // If (not every invoker has the same weight & at least one invoker's weight>0), select randomly based on 
             // totalWeight.
-            int offsetWeight = ThreadLocalRandom.current().nextInt(totalWeight) + 1;
+            int offsetWeight = ThreadLocalRandom.current().nextInt(totalWeight);
             // Return a invoker based on the random value.
             for (int i = 0; i < leastCount; i++) {
                 int leastIndex = leastIndexes[i];
-                offsetWeight -= getWeight(invokers.get(leastIndex), invocation);
-                if (offsetWeight <= 0) {
+                offsetWeight -= weights[leastIndex];
+                if (offsetWeight < 0) {
                     return invokers.get(leastIndex);
                 }
             }

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/loadbalance/RandomLoadBalance.java

@@ -25,21 +25,30 @@
 
 /**
  * random load balance.
- *
  */
 public class RandomLoadBalance extends AbstractLoadBalance {
 
     public static final String NAME = "random";
 
     @Override
     protected <T> Invoker<T> doSelect(List<Invoker<T>> invokers, URL url, Invocation invocation) {
-        int length = invokers.size(); // Number of invokers
-        boolean sameWeight = true; // Every invoker has the same weight?
+        // Number of invokers
+        int length = invokers.size();
+        // Every invoker has the same weight?
+        boolean sameWeight = true;
+        // the weight of every invokers
+        int[] weights = new int[length];
+        // the first invoker's weight
         int firstWeight = getWeight(invokers.get(0), invocation);
-        int totalWeight = firstWeight; // The sum of weights
+        weights[0] = firstWeight;
+        // The sum of weights
+        int totalWeight = firstWeight;
         for (int i = 1; i < length; i++) {
             int weight = getWeight(invokers.get(i), invocation);
-            totalWeight += weight; // Sum
+            // save for later use
+            weights[i] = weight;
+            // Sum
+            totalWeight += weight;
             if (sameWeight && weight != firstWeight) {
                 sameWeight = false;
             }
@@ -49,7 +58,7 @@ protected <T> Invoker<T> doSelect(List<Invoker<T>> invokers, URL url, Invocation
             int offset = ThreadLocalRandom.current().nextInt(totalWeight);
             // Return a invoker based on the random value.
             for (int i = 0; i < length; i++) {
-                offset -= getWeight(invokers.get(i), invocation);
+                offset -= weights[i];
                 if (offset < 0) {
                     return invokers.get(i);
                 }

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/loadbalance/RoundRobinLoadBalance.java

@@ -101,9 +101,7 @@ protected <T> Invoker<T> doSelect(List<Invoker<T>> invokers, URL url, Invocation
             String identifyString = invoker.getUrl().toIdentityString();
             WeightedRoundRobin weightedRoundRobin = map.get(identifyString);
             int weight = getWeight(invoker, invocation);
-            if (weight < 0) {
-                weight = 0;
-            }
+
             if (weightedRoundRobin == null) {
                 weightedRoundRobin = new WeightedRoundRobin();
                 weightedRoundRobin.setWeight(weight);

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/merger/ArrayMerger.java

@@ -16,6 +16,7 @@
  */
 package org.apache.dubbo.rpc.cluster.merger;
 
+import org.apache.dubbo.common.utils.ArrayUtils;
 import org.apache.dubbo.rpc.cluster.Merger;
 
 import java.lang.reflect.Array;
@@ -25,34 +26,48 @@ public class ArrayMerger implements Merger<Object[]> {
     public static final ArrayMerger INSTANCE = new ArrayMerger();
 
     @Override
-    public Object[] merge(Object[]... others) {
-        if (others.length == 0) {
-            return null;
+    public Object[] merge(Object[]... items) {
+        if (ArrayUtils.isEmpty(items)) {
+            return new Object[0];
         }
+
+        int i = 0;
+        while (i < items.length && items[i] == null) {
+            i++;
+        }
+
+        if (i == items.length) {
+            return new Object[0];
+        }
+
+        Class<?> type = items[i].getClass().getComponentType();
+
         int totalLen = 0;
-        for (int i = 0; i < others.length; i++) {
-            Object item = others[i];
-            if (item != null && item.getClass().isArray()) {
-                totalLen += Array.getLength(item);
-            } else {
-                throw new IllegalArgumentException((i + 1) + "th argument is not an array");
+        for (; i < items.length; i++) {
+            if (items[i] == null) {
+                continue;
+            }
+            Class<?> itemType = items[i].getClass().getComponentType();
+            if (itemType != type) {
+                throw new IllegalArgumentException("Arguments' types are different");
             }
+            totalLen += items[i].length;
         }
 
         if (totalLen == 0) {
-            return null;
+            return new Object[0];
         }
 
-        Class<?> type = others[0].getClass().getComponentType();
-
         Object result = Array.newInstance(type, totalLen);
+
         int index = 0;
-        for (Object array : others) {
-            for (int i = 0; i < Array.getLength(array); i++) {
-                Array.set(result, index++, Array.get(array, i));
+        for (Object[] array : items) {
+            if (array != null) {
+                for (int j = 0; j < array.length; j++) {
+                    Array.set(result, index++, array[j]);
+                }
             }
         }
         return (Object[]) result;
     }
-
 }

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/merger/BooleanArrayMerger.java

@@ -17,21 +17,29 @@
 
 package org.apache.dubbo.rpc.cluster.merger;
 
+import org.apache.dubbo.common.utils.ArrayUtils;
 import org.apache.dubbo.rpc.cluster.Merger;
 
 public class BooleanArrayMerger implements Merger<boolean[]> {
 
     @Override
     public boolean[] merge(boolean[]... items) {
+        if (ArrayUtils.isEmpty(items)) {
+            return new boolean[0];
+        }
         int totalLen = 0;
         for (boolean[] array : items) {
-            totalLen += array.length;
+            if (array != null) {
+                totalLen += array.length;
+            }
         }
         boolean[] result = new boolean[totalLen];
         int index = 0;
         for (boolean[] array : items) {
-            for (boolean item : array) {
-                result[index++] = item;
+            if (array != null) {
+                for (boolean item : array) {
+                    result[index++] = item;
+                }
             }
         }
         return result;

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/merger/ByteArrayMerger.java

@@ -17,21 +17,29 @@
 
 package org.apache.dubbo.rpc.cluster.merger;
 
+import org.apache.dubbo.common.utils.ArrayUtils;
 import org.apache.dubbo.rpc.cluster.Merger;
 
 public class ByteArrayMerger implements Merger<byte[]> {
 
     @Override
     public byte[] merge(byte[]... items) {
+        if (ArrayUtils.isEmpty(items)) {
+            return new byte[0];
+        }
         int total = 0;
         for (byte[] array : items) {
-            total += array.length;
+            if (array != null) {
+                total += array.length;
+            }
         }
         byte[] result = new byte[total];
         int index = 0;
         for (byte[] array : items) {
-            for (byte item : array) {
-                result[index++] = item;
+            if (array != null) {
+                for (byte item : array) {
+                    result[index++] = item;
+                }
             }
         }
         return result;

dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/merger/CharArrayMerger.java

@@ -17,21 +17,29 @@
 
 package org.apache.dubbo.rpc.cluster.merger;
 
+import org.apache.dubbo.common.utils.ArrayUtils;
 import org.apache.dubbo.rpc.cluster.Merger;
 
 public class CharArrayMerger implements Merger<char[]> {
 
     @Override
     public char[] merge(char[]... items) {
+        if (ArrayUtils.isEmpty(items)) {
+            return new char[0];
+        }
         int total = 0;
         for (char[] array : items) {
-            total += array.length;
+            if (array != null) {
+                total += array.length;
+            }
         }
         char[] result = new char[total];
         int index = 0;
         for (char[] array : items) {
-            for (char item : array) {
-                result[index++] = item;
+            if (array != null) {
+                for (char item : array) {
+                    result[index++] = item;
+                }
             }
         }
         return result;