Formatted code. Added javadoc. Upgraded artifacts.

pom.xml

@@ -7,7 +7,7 @@
     <groupId>com.github.yvasyliev</groupId>
     <artifactId>deezer-api</artifactId>
     <packaging>jar</packaging>
-    <version>1.1.4</version>
+    <version>1.2.0</version>
     <name>Deezer API Java Library</name>
     <description>A Java implementation of Deezer API.</description>
     <url>https://github.com/yvasyliev/deezer-api</url>
@@ -30,17 +30,17 @@
         <dependency>
             <groupId>org.slf4j</groupId>
             <artifactId>slf4j-api</artifactId>
-            <version>2.0.5</version>
+            <version>2.0.6</version>
         </dependency>
         <dependency>
             <groupId>com.google.code.gson</groupId>
             <artifactId>gson</artifactId>
-            <version>2.10</version>
+            <version>2.10.1</version>
         </dependency>
         <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter</artifactId>
-            <version>5.9.1</version>
+            <version>5.9.2</version>
             <scope>test</scope>
         </dependency>
         <dependency>
@@ -169,12 +169,12 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-surefire-plugin</artifactId>
-                <version>3.0.0-M7</version>
+                <version>3.0.0-M8</version>
                 <dependencies>
                     <dependency>
                         <groupId>org.junit.jupiter</groupId>
                         <artifactId>junit-jupiter-engine</artifactId>
-                        <version>5.9.1</version>
+                        <version>5.9.2</version>
                     </dependency>
                 </dependencies>
             </plugin>

src/main/java/api/deezer/http/HttpClient.java

@@ -1,7 +1,6 @@
 package api.deezer.http;
 
 import java.io.IOException;
-import java.io.OutputStream;
 
 /**
  * Executes HTTP requests.
@@ -15,5 +14,4 @@ public interface HttpClient {
      * @throws IOException if errors occur.
      */
     HttpResponse execute(HttpRequest httpRequest) throws IOException;
-
 }

src/main/java/api/deezer/http/HttpRequest.java

@@ -30,8 +30,7 @@ public interface HttpRequest {
     /**
      * File as bytes.
      *
-     * @return the file as bytes
+     * @return the file as bytes.
      */
     HttpRequestFilePart[] getFileParts();
-
 }

src/main/java/api/deezer/http/HttpRequestFilePart.java

@@ -1,19 +1,47 @@
 package api.deezer.http;
 
+/**
+ * A file to upload as {@code multipart/form-data}.
+ */
 public class HttpRequestFilePart {
+    /**
+     * Form field name.
+     */
+    private final String name;
 
-    private String name = null;
-    private String filename = null;
-    private String contentType = null;
-    private String contentTransferEncoding = null;
-    private byte[] value = null;
+    /**
+     * File data.
+     */
+    private final byte[] value;
+
+    /**
+     * Filename.
+     */
+    private String filename;
+
+    /**
+     * Form field content type.
+     */
+    private String contentType;
+
+    /**
+     * Content encoding.
+     */
+    private String contentTransferEncoding;
 
     public HttpRequestFilePart(final String name, final byte[] value) {
         this.name = name;
         this.value = value;
     }
 
-    public static HttpRequestFilePart image(final String name, final byte[] value){
+    /**
+     * Creates an instance of {@link HttpRequestFilePart} with a PNG image as a value.
+     *
+     * @param name  form field name.
+     * @param value image data.
+     * @return instance of {@link HttpRequestFilePart}.
+     */
+    public static HttpRequestFilePart png(final String name, final byte[] value) {
         HttpRequestFilePart image = new HttpRequestFilePart(name, value);
         image.setContentType("image/png");
         image.setFilename("image.png");
@@ -51,5 +79,4 @@ public void setContentTransferEncoding(String contentTransferEncoding) {
     public byte[] getValue() {
         return value;
     }
-
 }

src/main/java/api/deezer/http/impl/DeezerRequest.java

@@ -30,7 +30,7 @@ public abstract class DeezerRequest<Response> implements HttpRequest {
     private final Map<String, String> params;
 
     /**
-     * File
+     * File.
      */
     private final HttpRequestFilePart[] parts;
 

src/main/java/api/deezer/http/impl/DefaultHttpClient.java

@@ -8,7 +8,10 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.io.*;
+import java.io.BufferedReader;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.io.InputStreamReader;
 import java.net.HttpURLConnection;
 import java.net.URL;
 import java.util.Map;
@@ -60,6 +63,13 @@ public HttpResponse execute(HttpRequest httpRequest) throws IOException {
         }
     }
 
+    /**
+     * Creates GET request.
+     *
+     * @param httpRequest request data.
+     * @return {@link HttpURLConnection}.
+     * @throws IOException if errors occur.
+     */
     private static HttpURLConnection prepareRegularRequest(HttpRequest httpRequest) throws IOException {
         HttpURLConnection connection = (HttpURLConnection) new URL(httpRequest.getUrl()).openConnection();
         connection.setRequestMethod(httpRequest.getRequestMethod());
@@ -74,7 +84,13 @@ private static HttpURLConnection prepareRegularRequest(HttpRequest httpRequest)
         return connection;
     }
 
-
+    /**
+     * Creates POST request.
+     *
+     * @param httpRequest request data.
+     * @return {@link HttpURLConnection}.
+     * @throws IOException if errors occur.
+     */
     private static HttpURLConnection prepareMultipartRequest(HttpRequest httpRequest) throws IOException {
         Map<String, String> params = httpRequest.getParams();
         String urlParams = "";
@@ -109,7 +125,4 @@ private static HttpURLConnection prepareMultipartRequest(HttpRequest httpRequest
         }
         return connection;
     }
-
-
-
 }

src/main/java/api/deezer/requests/PlaylistRequests.java

@@ -119,7 +119,7 @@ public DeezerRequest<Boolean> uploadPicture(long playlistId, final String upload
                 property("playlist.picture", playlistId),
                 params,
                 Boolean.class,
-                new HttpRequestFilePart[]{ HttpRequestFilePart.image("file", image) }
+                new HttpRequestFilePart[]{ HttpRequestFilePart.png("file", image) }
         );
     }