fix sign v2 bug.

Author: huiguangjun

src/main/java/com/aliyun/oss/internal/SignV2Utils.java

@@ -237,18 +237,23 @@ private static String buildCanonicalizedResource(String resourcePath, Map<String
         builder.append(uriEncoding(resourcePath));
 
         if (parameters != null) {
-            String[] parameterNames = parameters.keySet().toArray(new String[parameters.size()]);
-            Arrays.sort(parameterNames);
+            TreeMap<String, String> canonicalizedParams = new TreeMap<String, String>();
+            for (Map.Entry<String, String> param : parameters.entrySet()) {
+                if (param.getValue() != null ) {
+                    canonicalizedParams.put(uriEncoding(param.getKey()), uriEncoding(param.getValue()));
+                }
+                else {
+                    canonicalizedParams.put(uriEncoding(param.getKey()), null);
+                }
+            }
 
             char separator = '?';
-            for (String paramName : parameterNames) {
+            for (Map.Entry<String, String> entry : canonicalizedParams.entrySet()) {
                 builder.append(separator);
-                builder.append(uriEncoding(paramName));
-                String paramValue = parameters.get(paramName);
-                if (paramValue != null && !paramValue.isEmpty()) {
-                    builder.append("=").append(uriEncoding(paramValue));
+                builder.append(entry.getKey());
+                if (entry.getValue() != null && !entry.getValue().isEmpty()) {
+                    builder.append("=").append(entry.getValue());
                 }
-
                 separator = '&';
             }
         }

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

@@ -51,6 +51,12 @@ public void testSignV2() {
             request.addAdditionalHeaderName("x-oss-head1");
             request.addAdditionalHeaderName("abc");
             request.addParameter("param1", "value1");
+            request.addParameter("|param1", "value2");
+            request.addParameter("+param1", "value3");
+            request.addParameter("|param1", "value4");
+            request.addParameter("+param2", "");
+            request.addParameter("|param2", null);
+            request.addParameter("param2", "");
 
             ossClient.putObject(request);
         } catch (Exception e) {
@@ -77,7 +83,7 @@ public void testGenerateSignedV2URL() {
         String filePath;
 
         try {
-            filePath = genFixedLengthFile(1 * 1024 * 1024); //1MB
+            filePath = genFixedLengthFile(100); //1MB
             PutObjectRequest putObjectRequest = new PutObjectRequest(bucket, key, new File(filePath));
 
             ossClient.putObject(putObjectRequest);
@@ -114,7 +120,7 @@ public void testSwitchSignatureVersion() {
         String filePath;
 
         try {
-            filePath = genFixedLengthFile(1 * 1024 * 1024); //1MB
+            filePath = genFixedLengthFile(100);
 
             ossClient.putObject(bucket, key, new File(filePath));