Make PendingResult#await throw specific Exception

src/main/java/com/google/maps/GeoApiContext.java

@@ -20,7 +20,6 @@
 import com.google.maps.errors.OverQueryLimitException;
 import com.google.maps.internal.ApiConfig;
 import com.google.maps.internal.ApiResponse;
-import com.google.maps.internal.ExceptionResult;
 import com.google.maps.internal.ExceptionsAllowedToRetry;
 import com.google.maps.internal.UrlSigner;
 
@@ -30,6 +29,8 @@
 import java.io.UnsupportedEncodingException;
 import java.net.Proxy;
 import java.net.URLEncoder;
+import java.security.InvalidKeyException;
+import java.security.NoSuchAlgorithmException;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 
@@ -115,7 +116,8 @@ <T, R extends ApiResponse<T>> PendingResult<T> get(ApiConfig config, Class<? ext
       try {
         query.append(URLEncoder.encode(param.getValue(), "UTF-8"));
       } catch (UnsupportedEncodingException e) {
-        return new ExceptionResult<T>(e);
+        // This should never happen. UTF-8 support is required for every Java implementation.
+        throw new IllegalStateException(e);
       }
     }
 
@@ -143,7 +145,8 @@ <T, R extends ApiResponse<T>> PendingResult<T> get(ApiConfig config, Class<? ext
       try {
         query.append(URLEncoder.encode(params[i], "UTF-8"));
       } catch (UnsupportedEncodingException e) {
-        return new ExceptionResult<T>(e);
+        // This should never happen. UTF-8 support is required for every Java implementation.
+        throw new IllegalStateException(e);
       }
     }
 
@@ -170,12 +173,7 @@ <T, R extends ApiResponse<T>> PendingResult<T> post(ApiConfig config,
     }
 
     if (config.supportsClientId && clientId != null) {
-      try {
-        String signature = urlSigner.getSignature(url.toString());
-        url.append("&signature=").append(signature);
-      } catch (Exception e) {
-        return new ExceptionResult<T>(e);
-      }
+      url.append("&signature=").append(urlSigner.getSignature(url.toString()));
     }
 
     String hostName = config.hostName;
@@ -213,12 +211,7 @@ private <T, R extends ApiResponse<T>> PendingResult<T> getWithPath(Class<R> claz
     url.append(encodedPath);
 
     if (canUseClientId && clientId != null) {
-      try {
-        String signature = urlSigner.getSignature(url.toString());
-        url.append("&signature=").append(signature);
-      } catch (Exception e) {
-        return new ExceptionResult<T>(e);
-      }
+      url.append("&signature=").append(urlSigner.getSignature(url.toString()));
     }
 
     if (baseUrlOverride != null) {
@@ -258,7 +251,11 @@ public GeoApiContext setApiKey(String apiKey) {
 
   public GeoApiContext setEnterpriseCredentials(String clientId, String cryptographicSecret) {
     this.clientId = clientId;
-    this.urlSigner = new UrlSigner(cryptographicSecret);
+    try {
+      this.urlSigner = new UrlSigner(cryptographicSecret);
+    } catch (NoSuchAlgorithmException | InvalidKeyException e) {
+      throw new IllegalStateException(e);
+    }
     return this;
   }
 

src/main/java/com/google/maps/PendingResult.java

@@ -15,6 +15,10 @@
 
 package com.google.maps;
 
+import com.google.maps.errors.ApiException;
+
+import java.io.IOException;
+
 /**
  * Represents a pending result from an API call.
  *
@@ -33,7 +37,7 @@ public interface PendingResult<T> {
    *
    * @return The result.
    */
-  T await() throws Exception;
+  T await() throws ApiException, InterruptedException, IOException;
 
   /**
    * Performs the request synchronously, ignoring exceptions while performing the request and errors

src/main/java/com/google/maps/PendingResultBase.java

@@ -15,10 +15,12 @@
 
 package com.google.maps;
 
+import com.google.maps.errors.ApiException;
 import com.google.maps.internal.ApiConfig;
 import com.google.maps.internal.ApiResponse;
 import com.google.maps.internal.StringJoin.UrlValue;
 
+import java.io.IOException;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
@@ -51,7 +53,7 @@ public final void setCallback(Callback<T> callback) {
   }
 
   @Override
-  public final T await() throws Exception {
+  public final T await() throws ApiException, InterruptedException, IOException {
     PendingResult<T> request = makeRequest();
     return request.await();
   }
@@ -75,12 +77,15 @@ private PendingResult<T> makeRequest() {
           "'await', 'awaitIgnoreError' or 'setCallback' was already called.");
     }
     validateRequest();
-    if(config.requestVerb == "GET") {
-      delegate = context.get(config, responseClass, params);
-    } else if (config.requestVerb == "POST") {
-      delegate = context.post(config, responseClass, params);
+    switch (config.requestVerb) {
+      case "GET":
+        return delegate = context.get(config, responseClass, params);
+      case "POST":
+        return delegate = context.post(config, responseClass, params);
+      default:
+        throw new IllegalStateException(
+            String.format("Unexpected request method '%s'", config.requestVerb));
     }
-    return delegate;
   }
 
   protected abstract void validateRequest();

src/main/java/com/google/maps/internal/GaePendingResult.java

@@ -27,6 +27,7 @@
 import com.google.maps.PendingResult;
 import com.google.maps.PhotoRequest;
 import com.google.maps.errors.ApiException;
+import com.google.maps.errors.UnknownErrorException;
 import com.google.maps.model.AddressComponentType;
 import com.google.maps.model.AddressType;
 import com.google.maps.model.Distance;
@@ -49,6 +50,7 @@
 import java.nio.charset.Charset;
 import java.util.Arrays;
 import java.util.List;
+import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Future;
 
 
@@ -68,7 +70,6 @@ public class GaePendingResult<T, R extends ApiResponse<T>>
   private final Integer maxRetries;
   private final ExceptionsAllowedToRetry exceptionsAllowedToRetry;
 
-  private Callback<T> callback;
   private long errorTimeOut;
   private int retryCounter = 0;
   private long cumulativeSleepTime = 0;
@@ -105,12 +106,18 @@ public void setCallback(Callback<T> callback) {
   }
 
   @Override
-  public T await() throws Exception {
-    HTTPResponse response = call.get();
-    if (response != null) {
-      return parseResponse(this, response);
-    } else {
-      throw new Exception(response.getResponseCode() + " " + new String(response.getContent()));
+  public T await() throws ApiException, IOException, InterruptedException {
+    try {
+      return parseResponse(this, call.get());
+    } catch (ExecutionException e) {
+      if (e.getCause() instanceof IOException) {
+        throw (IOException) e.getCause();
+      } else {
+        // According to
+        // https://cloud.google.com/appengine/docs/standard/java/javadoc/com/google/appengine/api/urlfetch/URLFetchService
+        // all exceptions should be subclass of IOException so this should not happen.
+        throw new UnknownErrorException("Unexpected exception from " + e.getMessage());
+      }
     }
   }
 
@@ -130,7 +137,8 @@ public void cancel() {
 
 
   @SuppressWarnings("unchecked")
-  private T parseResponse(GaePendingResult<T, R> request, HTTPResponse response) throws Exception {
+  private T parseResponse(GaePendingResult<T, R> request, HTTPResponse response)
+      throws IOException, ApiException, InterruptedException {
     if (shouldRetry(response)) {
       // Retry is a blocking method, but that's OK. If we're here, we're either in an await()
       // call, which is blocking anyway, or we're handling a callback in a separate thread.
@@ -212,7 +220,7 @@ private T parseResponse(GaePendingResult<T, R> request, HTTPResponse response) t
     }
   }
 
-  private T retry() throws Exception {
+  private T retry() throws IOException, ApiException, InterruptedException  {
     retryCounter++;
     LOG.info("Retrying request. Retry #{}",retryCounter);
     this.call = client.fetchAsync(request);

src/main/java/com/google/maps/internal/OkHttpPendingResult.java

@@ -115,23 +115,23 @@ public void setCallback(Callback<T> callback) {
   private class QueuedResponse {
     private final OkHttpPendingResult<T, R> request;
     private final Response response;
-    private final Exception e;
+    private final IOException e;
 
     public QueuedResponse(OkHttpPendingResult<T, R> request, Response response) {
       this.request = request;
       this.response = response;
       this.e = null;
     }
 
-    public QueuedResponse(OkHttpPendingResult<T, R> request, Exception e) {
+    public QueuedResponse(OkHttpPendingResult<T, R> request, IOException e) {
       this.request = request;
       this.response = null;
       this.e = e;
     }
   }
 
   @Override
-  public T await() throws Exception {
+  public T await() throws ApiException, IOException, InterruptedException {
     // Handle sleeping for retried requests
     if (retryCounter > 0) {
       // 0.5 * (1.5 ^ i) represents an increased sleep time of 1.5x per iteration,
@@ -210,7 +210,8 @@ public void onResponse(Response response) throws IOException {
   }
 
   @SuppressWarnings("unchecked")
-  private T parseResponse(OkHttpPendingResult<T, R> request, Response response) throws Exception {
+  private T parseResponse(OkHttpPendingResult<T, R> request, Response response)
+      throws ApiException, InterruptedException, IOException {
     if (shouldRetry(response)) {
       // Retry is a blocking method, but that's OK. If we're here, we're either in an await()
       // call, which is blocking anyway, or we're handling a callback in a separate thread.
@@ -284,7 +285,7 @@ private T parseResponse(OkHttpPendingResult<T, R> request, Response response) th
     }
   }
 
-  private T retry() throws Exception {
+  private T retry() throws ApiException, InterruptedException, IOException {
     retryCounter++;
     LOG.info("Retrying request. Retry #" + retryCounter);
     this.call = client.newCall(request);

src/main/java/com/google/maps/internal/UrlSigner.java

@@ -30,9 +30,10 @@
  * a client ID</a> for more detail on this protocol.
  */
 public class UrlSigner {
-  private final SecretKeySpec key;
+  private static final String ALGORITHM_HMAC_SHA1 = "HmacSHA1";
+  private final Mac mac;
 
-  public UrlSigner(final String keyString) {
+  public UrlSigner(final String keyString) throws NoSuchAlgorithmException, InvalidKeyException {
     // Convert from URL-safe base64 to regular base64.
     String base64 = keyString.replace('-', '+').replace('_', '/');
 
@@ -41,17 +42,16 @@ public UrlSigner(final String keyString) {
       // NOTE: don't log the exception, in case some of the private key leaks to an end-user.
       throw new IllegalArgumentException("Private key is invalid.");
     }
-    this.key = new SecretKeySpec(decodedKey.toByteArray(), "HmacSHA1");
+
+    // TODO(macd): add test
+    mac = Mac.getInstance(ALGORITHM_HMAC_SHA1);
+    mac.init(new SecretKeySpec(decodedKey.toByteArray(), ALGORITHM_HMAC_SHA1));
   }
 
   /**
    * Generate url safe HmacSHA1 of a path.
    */
-  public String getSignature(String path)
-      throws NoSuchAlgorithmException, InvalidKeyException {
-    // TODO(macd): add test
-    Mac mac = Mac.getInstance("HmacSHA1");
-    mac.init(key);
+  public String getSignature(String path) {
     byte[] digest = mac.doFinal(path.getBytes());
     return ByteString.of(digest).base64().replace('+', '-').replace('/', '_');
   }