Android: Add AndroidHTTPDownloader class

android/app/src/main/java/com/github/stenzek/duckstation/URLDownloader.java

@@ -0,0 +1,92 @@
+package com.github.stenzek.duckstation;
+
+import java.io.BufferedInputStream;
+import java.io.BufferedOutputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+/**
+ * Helper class for exposing HTTP downloads to native code without pulling in an external
+ * dependency for doing so.
+ */
+public class URLDownloader {
+    private int statusCode = -1;
+    private byte[] data = null;
+
+    public URLDownloader() {
+    }
+
+    static private HttpURLConnection getConnection(String url) {
+        try {
+            final URL parsedUrl = new URL(url);
+            HttpURLConnection connection = (HttpURLConnection) parsedUrl.openConnection();
+            if (connection == null)
+                throw new RuntimeException(String.format("openConnection(%s) returned null", url));
+
+            return connection;
+        } catch (Exception e) {
+            e.printStackTrace();
+            return null;
+        }
+    }
+
+    public int getStatusCode() {
+        return statusCode;
+    }
+
+    public byte[] getData() {
+        return data;
+    }
+
+    private boolean download(HttpURLConnection connection) {
+        try {
+            statusCode = connection.getResponseCode();
+            if (statusCode != HttpURLConnection.HTTP_OK)
+                return false;
+
+            final InputStream inStream = new BufferedInputStream(connection.getInputStream());
+            final ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+            final int CHUNK_SIZE = 128 * 1024;
+            final byte[] chunk = new byte[CHUNK_SIZE];
+            int len;
+            while ((len = inStream.read(chunk)) > 0) {
+                outputStream.write(chunk, 0, len);
+            }
+
+            data = outputStream.toByteArray();
+            return true;
+        } catch (Exception e) {
+            e.printStackTrace();
+            return false;
+        }
+    }
+
+    public boolean get(String url) {
+        final HttpURLConnection connection = getConnection(url);
+        if (connection == null)
+            return false;
+
+        return download(connection);
+    }
+
+    public boolean post(String url, byte[] postData) {
+        final HttpURLConnection connection = getConnection(url);
+        if (connection == null)
+            return false;
+
+        try {
+            connection.setDoOutput(true);
+            connection.setChunkedStreamingMode(0);
+
+            OutputStream postStream = new BufferedOutputStream(connection.getOutputStream());
+            postStream.write(postData);
+            return download(connection);
+        } catch (Exception e) {
+            e.printStackTrace();
+            return false;
+        }
+    }
+}