add getConnectionPoolStats API.

Author: huiguangjun

src/main/java/com/aliyun/oss/OSS.java

@@ -68,6 +68,11 @@ public interface OSS {
      */
     public void shutdown();
 
+    /**
+     * Get the statistics of the connection pool.
+     */
+    public String getConnectionPoolStats();
+
     /**
      * Creates {@link Bucket} instance. The bucket name specified must be
      * globally unique and follow the naming rules from

src/main/java/com/aliyun/oss/OSSClient.java

@@ -1779,4 +1779,12 @@ public void shutdown() {
         }
     }
 
+    @Override
+    public String getConnectionPoolStats() {
+        try {
+            return serviceClient.getConnectionPoolStats();
+        } catch (Exception e) {
+        }
+        return "";
+    }
 }

src/main/java/com/aliyun/oss/common/comm/DefaultServiceClient.java

@@ -322,7 +322,7 @@ public void shutdown() {
     }
 
     @Override
-    protected String getConnectionPoolStats() {
+    public String getConnectionPoolStats() {
         if (connectionManager != null && connectionManager instanceof PoolingHttpClientConnectionManager) {
             PoolingHttpClientConnectionManager conn = (PoolingHttpClientConnectionManager)connectionManager;
             return conn.getTotalStats().toString();

src/main/java/com/aliyun/oss/common/comm/ServiceClient.java

@@ -320,7 +320,7 @@ private String formatSlowRequestLog(RequestMessage request, ResponseMessage resp
 
     public abstract void shutdown();
 
-    protected String getConnectionPoolStats() {
+    public String getConnectionPoolStats() {
         return "";
     };
 

src/test/java/com/aliyun/oss/integrationtests/ClientBuilderTest.java

@@ -242,6 +242,7 @@ public void testClientBuilderWithInvalidEndpoint() {
     public void testClientBuilderLogConnectionPoolStats() {
         OSSClient client = null;
         ClientBuilderConfiguration config = new ClientBuilderConfiguration();
+        config.setMaxConnections(10);
         Assert.assertEquals(config.isLogConnectionPoolStatsEnable(), false);
         config.setLogConnectionPoolStats(true);
         Assert.assertEquals(config.isLogConnectionPoolStatsEnable(), true);
@@ -251,8 +252,43 @@ public void testClientBuilderLogConnectionPoolStats() {
                     new DefaultCredentialProvider(TestConfig.OSS_TEST_ACCESS_KEY_ID,
                             TestConfig.OSS_TEST_ACCESS_KEY_SECRET),
                     config);
-            BucketInfo info = client.getBucketInfo(bucketName);
-            Assert.assertEquals(info.getBucket().getName(), bucketName);
+
+            final OSSClient innerClient = client;
+
+            int threadCount = 20;
+            Thread[] ts = new Thread[threadCount];
+            for (int i = 0; i < threadCount; i++) {
+                final int seqNum = i;
+                Runnable r = new Runnable() {
+
+                    @Override
+                    public void run() {
+                        try {
+                            BucketInfo info = innerClient.getBucketInfo(bucketName);
+                            Assert.assertEquals(info.getBucket().getName(), bucketName);
+                        } catch (Exception e) {
+                            System.out.println(e.getMessage());
+                        }
+                    }
+                };
+
+                ts[i] = new Thread(r);
+            }
+
+            for (int i = 0; i < threadCount; i++) {
+                ts[i].start();
+            }
+
+            for (int i = 0; i < threadCount; i++) {
+                ts[i].join();
+            }
+
+            String str  = client.getConnectionPoolStats();
+            Assert.assertTrue(str.indexOf("leased: 0") != -1);
+            Assert.assertTrue(str.indexOf("pending: 0") != -1);
+            Assert.assertTrue(str.indexOf("available: 10") != -1);
+            Assert.assertTrue(str.indexOf("max: 10") != -1);
+
         } catch (Exception e) {
             Assert.assertTrue(false);
         } finally {