Gracefully handle calling make_meta_request on closed S3 client (#725)

src/main/java/software/amazon/awssdk/crt/s3/S3Client.java

@@ -122,16 +122,22 @@ private void onShutdownComplete() {
 
     public S3MetaRequest makeMetaRequest(S3MetaRequestOptions options) {
 
+        if(isNull()) {
+            Log.log(Log.LogLevel.Error, Log.LogSubject.S3Client,
+                    "S3Client.makeMetaRequest has invalid client. The client can not be used after it is closed.");
+            throw new IllegalStateException("S3Client.makeMetaRequest has invalid client. The client can not be used after it is closed.");
+        }
+
         if (options.getHttpRequest() == null) {
             Log.log(Log.LogLevel.Error, Log.LogSubject.S3Client,
                     "S3Client.makeMetaRequest has invalid options; Http Request cannot be null.");
-            return null;
+            throw new IllegalArgumentException("S3Client.makeMetaRequest has invalid options; Http Request cannot be null.");
         }
 
         if (options.getResponseHandler() == null) {
             Log.log(Log.LogLevel.Error, Log.LogSubject.S3Client,
                     "S3Client.makeMetaRequest has invalid options; Response Handler cannot be null.");
-            return null;
+            throw new IllegalArgumentException("S3Client.makeMetaRequest has invalid options; Response Handler cannot be null.");
         }
 
         S3MetaRequest metaRequest = new S3MetaRequest();

src/test/java/software/amazon/awssdk/crt/test/S3ClientTest.java

@@ -333,6 +333,36 @@ public void onFinished(S3FinishedResponseContext context) {
         }
     }
 
+    @Test
+    public void testS3GetAfterClientIsClose() {
+        skipIfAndroid();
+        skipIfNetworkUnavailable();
+        Assume.assumeTrue(hasAwsCredentials());
+        S3ClientOptions clientOptions = new S3ClientOptions().withRegion(REGION);
+        S3Client client = createS3Client(clientOptions);
+        client.close();
+        S3MetaRequestResponseHandler responseHandler = new S3MetaRequestResponseHandler() {
+
+            @Override
+            public int onResponseBody(ByteBuffer bodyBytesIn, long objectRangeStart, long objectRangeEnd) {
+                return 0;
+            }
+
+            @Override
+            public void onFinished(S3FinishedResponseContext context) {
+            }
+        };
+
+        HttpHeader[] headers = { new HttpHeader("Host", ENDPOINT) };
+        HttpRequest httpRequest = new HttpRequest("GET", "/get_object_test_1MB.txt", headers, null);
+
+        S3MetaRequestOptions metaRequestOptions = new S3MetaRequestOptions()
+                .withMetaRequestType(MetaRequestType.GET_OBJECT).withHttpRequest(httpRequest)
+                .withResponseHandler(responseHandler);
+
+        assertThrows(IllegalStateException.class, () -> client.makeMetaRequest(metaRequestOptions));
+    }
+
     @Test
     public void testS3CallbackExceptionIsProperlyPropagated() {
         skipIfAndroid();