Rework exception model

Author: LucaScorpion

README.md

@@ -24,30 +24,14 @@ To access devRant simply create a new `DevRant` object:
 DevRant devRant = new DevRant();
 ```
 
-Most object that are returned from `DevRant` are wrapped in a `Result` object.
-This will contain an optional result value, along with an error message.
-If the optional result is empty, then an error occurred and the error message will be set.
-For example:
-
-```
-Result<CommentedRant> result = devRant.getRant(832125);
-
-if (!result.getValue().isPresent()) {
-    System.out.println("An error occurred: " + result.getError());
-} else {
-    CommentedRant rant = result.getValue().get();
-    System.out.println(rant.getUser().getUsername() + '\n' + rant.getText());
-}
-```
-
 The `DevRant` class itself can be used to get specific rants and users.
 
 ```
 // Get a specific rant.
-Result<CommentedRant> rant = devRant.getRant(686001);
+CommentedRant rant = devRant.getRant(686001);
 
 // Get a user by username.
-Result<User> me = devRant.getUser("LucaScorpion");
+User me = devRant.getUser("LucaScorpion");
 ```
 
 The `DevRant` class contains 2 methods for getting to specific parts of the api.
@@ -56,13 +40,13 @@ This is used to access the rant and collab feeds.
 
 ```
 // Get the 10 latest rants.
-Result<List<Rant>> recent = devRant.getFeed().getRants(Sort.RECENT, 10, 0);
+List<Rant> recent = devRant.getFeed().getRants(Sort.RECENT, 10, 0);
 
 // Get the 10 best stories.
-Result<List<Rant>> stories = devRant.getFeed().getStories(Sort.TOP, 0);
+List<Rant> stories = devRant.getFeed().getStories(Sort.TOP, 0);
 
 // Get 10 collabs.
-Result<List<Collab>> collabs = devRant.getFeed().getCollabs(10);
+List<Collab> collabs = devRant.getFeed().getCollabs(10);
 ```
 
 Second, `getAuth()` which returns a `DevRantAuth` object, which is used to access user functionality.

src/main/java/com/scorpiac/javarant/DevRant.java

@@ -70,8 +70,9 @@ public DevRantAuth getAuth() {
      * @param id The id of the rant.
      * @return The rant.
      */
-    public Result<CommentedRant> getRant(int id) {
-        return requestHandler.get(ApiEndpoint.RANTS.toString() + '/' + id, CommentedRantResponse.class);
+    public CommentedRant getRant(int id) {
+        return requestHandler.get(ApiEndpoint.RANTS.toString() + '/' + id, CommentedRantResponse.class)
+                .getValue().orElseThrow(() -> new NoSuchRantException(id));
     }
 
     /**
@@ -80,16 +81,11 @@ public Result<CommentedRant> getRant(int id) {
      * @param username The username of the user.
      * @return The user.
      */
-    public Result<User> getUser(String username) {
-        Result<Integer> result = requestHandler.get(ApiEndpoint.USER_ID, UserIdResponse.class, new BasicNameValuePair("username", username));
+    public User getUser(String username) {
+        Integer result = requestHandler.get(ApiEndpoint.USER_ID, UserIdResponse.class, new BasicNameValuePair("username", username))
+                .getValue().orElseThrow(() -> new NoSuchUserException(username));
 
-        // Check the result.
-        if (!result.getValue().isPresent()) {
-            // When the username is invalid, no error message is returned by the API.
-            return new Result<>("Invalid username specified.");
-        }
-
-        return getUser(result.getValue().get());
+        return getUser(result);
     }
 
     /**
@@ -98,28 +94,23 @@ public Result<User> getUser(String username) {
      * @param id The id of the user.
      * @return The user.
      */
-    public Result<User> getUser(int id) {
-        Result<User> result = requestHandler.get(ApiEndpoint.USERS.toString() + '/' + id, UserResponse.class);
-
-        // Check the result.
-        if (!result.getValue().isPresent()) {
-            // When the user id is invalid, no error message is returned by the API.
-            return new Result<>("Invalid user id specified.");
-        }
+    public User getUser(int id) {
+        User user = requestHandler.get(ApiEndpoint.USERS.toString() + '/' + id, UserResponse.class)
+                .getValue().orElseThrow(() -> new NoSuchUserException(id));
 
         // Set the id, as that is not part of the response.
-        result.getValue().get().setId(id);
+        user.setId(id);
 
-        return result;
+        return user;
     }
 
     /**
      * Get a random rant.
      *
      * @return A random rant.
      */
-    public Result<Rant> getSurprise() {
-        return requestHandler.get(ApiEndpoint.SURPRISE, RantResponse.class);
+    public Rant getSurprise() {
+        return requestHandler.get(ApiEndpoint.SURPRISE, RantResponse.class).getValueOrError();
     }
 
     /**
@@ -128,8 +119,9 @@ public Result<Rant> getSurprise() {
      * @param id The id of the collab.
      * @return The collab.
      */
-    public Result<Collab> getCollab(int id) {
-        return requestHandler.get(ApiEndpoint.RANTS.toString() + '/' + id, CollabResponse.class);
+    public Collab getCollab(int id) {
+        return requestHandler.get(ApiEndpoint.RANTS.toString() + '/' + id, CollabResponse.class)
+                .getValue().orElseThrow(() -> new NoSuchRantException(id));
     }
 
     /**
@@ -143,17 +135,17 @@ public Result<Collab> getCollab(int id) {
     public boolean login(String username, char[] password) {
         logout();
 
-        Result<Auth> response = requestHandler.post(ApiEndpoint.AUTH_TOKEN, AuthResponse.class,
+        Auth response = requestHandler.post(ApiEndpoint.AUTH_TOKEN, AuthResponse.class,
                 new BasicNameValuePair("username", username),
                 new BasicNameValuePair("password", String.valueOf(password))
-        );
+        ).getValue().orElseThrow(() -> new DevRantException("Could not log in."));
 
         // Clear the password.
         for (int i = 0; i < password.length; i++) {
             password[i] = 0;
         }
 
-        response.getValue().ifPresent(r -> auth = r);
+        auth = response;
         return isLoggedIn();
     }
 

src/main/java/com/scorpiac/javarant/DevRantApiException.java

@@ -0,0 +1,7 @@
+package com.scorpiac.javarant;
+
+public class DevRantApiException extends RuntimeException {
+    public DevRantApiException(String message) {
+        super("A devRant API exception occurred: " + message);
+    }
+}

src/main/java/com/scorpiac/javarant/DevRantAuth.java

@@ -21,12 +21,12 @@ public class DevRantAuth {
      * @param vote The vote to cast.
      * @return The rant.
      */
-    public Result<Rant> voteRant(int id, Vote vote) {
+    public Rant voteRant(int id, Vote vote) {
         return devRant.getRequestHandler().post(
                 ApiEndpoint.RANTS.toString() + '/' + id + '/' + ApiEndpoint.VOTE.toString(),
                 RantResponse.class,
                 getParameters(vote.getOptions())
-        );
+        ).getValueOrError();
     }
 
     /**
@@ -36,12 +36,12 @@ public Result<Rant> voteRant(int id, Vote vote) {
      * @param vote The vote to cast.
      * @return The comment.
      */
-    public Result<Comment> voteComment(int id, Vote vote) {
+    public Comment voteComment(int id, Vote vote) {
         return devRant.getRequestHandler().post(
                 ApiEndpoint.COMMENTS.toString() + '/' + id + '/' + ApiEndpoint.VOTE.toString(),
                 CommentResponse.class,
                 getParameters(vote.getOptions())
-        );
+        ).getValueOrError();
     }
 
     private NameValuePair[] getParameters(List<NameValuePair> params) {

src/main/java/com/scorpiac/javarant/DevRantException.java

@@ -0,0 +1,11 @@
+package com.scorpiac.javarant;
+
+public class DevRantException extends RuntimeException {
+    public DevRantException(String message) {
+        super(message);
+    }
+
+    public DevRantException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

src/main/java/com/scorpiac/javarant/DevRantFeed.java

@@ -1,5 +1,6 @@
 package com.scorpiac.javarant;
 
+import com.scorpiac.javarant.responses.CollabsFeedResponse;
 import com.scorpiac.javarant.responses.RantsFeedResponse;
 import com.scorpiac.javarant.responses.ResultsFeedResponse;
 import org.apache.http.message.BasicNameValuePair;
@@ -21,12 +22,12 @@ public class DevRantFeed {
      * @param skip  How many rants to skip.
      * @return Rants from the feed.
      */
-    public Result<List<Rant>> getRants(Sort sort, int limit, int skip) {
+    public List<Rant> getRants(Sort sort, int limit, int skip) {
         return devRant.getRequestHandler().get(ApiEndpoint.RANTS, RantsFeedResponse.class,
                 new BasicNameValuePair("sort", sort.toString()),
                 new BasicNameValuePair("limit", String.valueOf(limit)),
                 new BasicNameValuePair("skip", String.valueOf(skip))
-        );
+        ).getValueOrError();
     }
 
     /**
@@ -35,10 +36,10 @@ public Result<List<Rant>> getRants(Sort sort, int limit, int skip) {
      * @param term The term to search for.
      * @return The search results.
      */
-    public Result<List<Rant>> search(String term) {
+    public List<Rant> search(String term) {
         return devRant.getRequestHandler().get(ApiEndpoint.SEARCH, ResultsFeedResponse.class,
                 new BasicNameValuePair("term", term)
-        );
+        ).getValueOrError();
     }
 
     /**
@@ -48,11 +49,11 @@ public Result<List<Rant>> search(String term) {
      * @param skip How many rants to skip.
      * @return Weekly rants from the feed.
      */
-    public Result<List<Rant>> getWeekly(Sort sort, int skip) {
+    public List<Rant> getWeekly(Sort sort, int skip) {
         return devRant.getRequestHandler().get(ApiEndpoint.WEEKLY, RantsFeedResponse.class,
                 new BasicNameValuePair("sort", sort.toString()),
                 new BasicNameValuePair("skip", String.valueOf(skip))
-        );
+        ).getValueOrError();
     }
 
     /**
@@ -62,11 +63,11 @@ public Result<List<Rant>> getWeekly(Sort sort, int skip) {
      * @param skip How many rants to skip.
      * @return Stories from the feed.
      */
-    public Result<List<Rant>> getStories(Sort sort, int skip) {
+    public List<Rant> getStories(Sort sort, int skip) {
         return devRant.getRequestHandler().get(ApiEndpoint.STORIES, RantsFeedResponse.class,
                 new BasicNameValuePair("sort", sort.toString()),
                 new BasicNameValuePair("skip", String.valueOf(skip))
-        );
+        ).getValueOrError();
     }
 
     /**
@@ -75,9 +76,9 @@ public Result<List<Rant>> getStories(Sort sort, int skip) {
      * @param limit How many rants to get.
      * @return Collabs from the feed.
      */
-    public Result<List<Collab>> getCollabs(int limit) {
-        return devRant.getRequestHandler().get(ApiEndpoint.COLLABS, RantsFeedResponse.class,
+    public List<Collab> getCollabs(int limit) {
+        return devRant.getRequestHandler().get(ApiEndpoint.COLLABS, CollabsFeedResponse.class,
                 new BasicNameValuePair("limit", String.valueOf(limit))
-        );
+        ).getValueOrError();
     }
 }

src/main/java/com/scorpiac/javarant/NoSuchRantException.java

@@ -0,0 +1,7 @@
+package com.scorpiac.javarant;
+
+public class NoSuchRantException extends RuntimeException {
+    public NoSuchRantException(int id) {
+        super("A rant with id " + id + " does not exist.");
+    }
+}

src/main/java/com/scorpiac/javarant/NoSuchUserException.java

@@ -0,0 +1,11 @@
+package com.scorpiac.javarant;
+
+public class NoSuchUserException extends RuntimeException {
+    public NoSuchUserException(String username) {
+        super("The user '" + username + "' does not exist.");
+    }
+
+    public NoSuchUserException(int id) {
+        super("A user with id " + id + " does not exist.");
+    }
+}

src/main/java/com/scorpiac/javarant/Result.java

@@ -0,0 +1,17 @@
+package com.scorpiac.javarant.responses;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.scorpiac.javarant.News;
+import com.scorpiac.javarant.Rant;
+
+import java.util.List;
+
+abstract class AbstractRantsFeedResponse<T extends Rant> extends Response<List<T>> {
+    @JsonProperty
+    private News news; // TODO: use this.
+
+    @JsonProperty
+    void setRants(List<T> rants) {
+        value = rants;
+    }
+}