Add HttpUtility

build.gradle.kts

@@ -11,7 +11,10 @@ plugins {
 }
 
 repositories.mavenCentral()
-dependencies.compileOnly("org.jetbrains:annotations:24.0.1")
+dependencies {
+    compileOnly("org.jetbrains:annotations:24.0.1")
+    compileOnly("com.google.code.gson:gson:2.3.1")
+}
 
 setupJava("xyz.srnyx", "1.0.0", "General Java utility library for srnyx's projects", JavaVersion.VERSION_1_8)
 setupPublishing(

src/main/java/xyz/srnyx/javautilities/HttpUtility.java

@@ -0,0 +1,162 @@
+package xyz.srnyx.javautilities;
+
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.net.HttpURLConnection;
+import java.net.URI;
+import java.util.function.Function;
+import java.util.stream.Collectors;
+
+
+/**
+ * Utility class for making HTTP requests
+ */
+public class HttpUtility {
+    /**
+     * Sends a GET request to the specified URL and returns the result of the specified function
+     *
+     * @param   userAgent   the user agent to use
+     * @param   url         the URL to request from
+     * @param   function    the function to apply to the {@link InputStreamReader}
+     *
+     * @param   <T>         the type of the result of the specified function
+     *
+     * @return              the result of the specified function, or null if the request failed
+     */
+    @Nullable
+    public static <T> T get(@NotNull String userAgent, @NotNull String url, Function<InputStreamReader, T> function) {
+        T result = null;
+        HttpURLConnection connection = null;
+        try {
+            connection = (HttpURLConnection) URI.create(url).toURL().openConnection();
+            connection.setRequestMethod("GET");
+            connection.setRequestProperty("User-Agent", userAgent);
+            if (connection.getResponseCode() == 404) return null;
+            result = function.apply(new InputStreamReader(connection.getInputStream()));
+        } catch (final IOException ignored) {
+            // Ignored
+        }
+        if (connection != null) connection.disconnect();
+        return result;
+    }
+
+    /**
+     * Sends a GET request to the specified URL and returns the result as a {@link String}
+     *
+     * @param   userAgent   the user agent to use
+     * @param   urlString   the URL to request from
+     *
+     * @return              the {@link String}, or null if the request failed
+     */
+    @Nullable
+    public static String getString(@NotNull String userAgent, @NotNull String urlString) {
+        return get(userAgent, urlString, reader -> new BufferedReader(reader).lines().collect(Collectors.joining("\n")));
+    }
+
+    /**
+     * Sends a GET request to the specified URL and returns the result as a {@link JsonElement}
+     *
+     * @param   userAgent   the user agent to use when retrieving the {@link JsonElement}
+     * @param   urlString   the URL to retrieve the {@link JsonElement} from
+     *
+     * @return              the {@link JsonElement} retrieved from the specified URL
+     */
+    @Nullable
+    public static JsonElement getJson(@NotNull String userAgent, @NotNull String urlString) {
+        return get(userAgent, urlString, reader -> new JsonParser().parse(reader));
+    }
+
+    /**
+     * Sends a POST request to the specified URL with the specified {@link JsonObject JSON data}
+     *
+     * @param   userAgent   the user agent to use
+     * @param   urlString   the URL to send the POST request to
+     * @param   data        the {@link JsonObject JSON data} to send with the POST request
+     *
+     * @return              the response code of the request
+     */
+    public static int postJson(@NotNull String userAgent, @NotNull String urlString, @NotNull JsonElement data) {
+        int responseCode = -1;
+        HttpURLConnection connection = null;
+        try {
+            connection = (HttpURLConnection) URI.create(urlString).toURL().openConnection();
+            connection.setRequestMethod("POST");
+            connection.setRequestProperty("User-Agent", userAgent);
+            connection.setRequestProperty("Content-Type", "application/json");
+            connection.setDoOutput(true);
+            connection.getOutputStream().write(data.toString().getBytes());
+            responseCode = connection.getResponseCode();
+        } catch (final IOException ignored) {
+            // Ignored
+        }
+        if (connection != null) connection.disconnect();
+        return responseCode;
+    }
+
+    /**
+     * Sends a PUT request to the specified URL with the specified {@link JsonElement JSON data}
+     *
+     * @param   userAgent   the user agent to use
+     * @param   urlString   the URL to send the PUT request to
+     * @param   data        the {@link JsonElement JSON data} to send with the PUT request
+     *
+     * @return              the response code of the request
+     */
+    public static int putJson(@NotNull String userAgent, @NotNull String urlString, @NotNull JsonElement data) {
+        int responseCode = -1;
+        HttpURLConnection connection = null;
+        try {
+            connection = (HttpURLConnection) URI.create(urlString).toURL().openConnection();
+            connection.setRequestMethod("PUT");
+            connection.setRequestProperty("User-Agent", userAgent);
+            connection.setRequestProperty("Content-Type", "application/json");
+            connection.setDoOutput(true);
+            connection.getOutputStream().write(data.toString().getBytes());
+            responseCode = connection.getResponseCode();
+        } catch (final IOException ignored) {
+            // Ignored
+        }
+        if (connection != null) connection.disconnect();
+        return responseCode;
+    }
+
+    /**
+     * Sends a DELETE request to the specified URL
+     *
+     * @param   userAgent   the user agent to use
+     * @param   urlString   the URL to send the DELETE request to
+     *
+     * @return              the response code of the request
+     */
+    public static int delete(@NotNull String userAgent, @NotNull String urlString) {
+        int responseCode = -1;
+        HttpURLConnection connection = null;
+        try {
+            connection = (HttpURLConnection) URI.create(urlString).toURL().openConnection();
+            connection.setRequestMethod("DELETE");
+            connection.setRequestProperty("User-Agent", userAgent);
+            responseCode = connection.getResponseCode();
+        } catch (final IOException ignored) {
+            // Ignored
+        }
+        if (connection != null) connection.disconnect();
+        return responseCode;
+    }
+
+    /**
+     * Constructs a new {@link HttpUtility} instance (illegal)
+     *
+     * @throws  UnsupportedOperationException   if this class is instantiated
+     */
+    private HttpUtility() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}