[LIB-9] Add ability to archive qrcode content

[chesshog.git] / chesshog-qrcode / src / main / java / org / hedgecode / chess / qrcode / zip / ZipContentUtils.java

diff --git a/chesshog-qrcode/src/main/java/org/hedgecode/chess/qrcode/zip/ZipContentUtils.java b/chesshog-qrcode/src/main/java/org/hedgecode/chess/qrcode/zip/ZipContentUtils.java
new file mode 100644 (file)
index 0000000..dfd7901
--- /dev/null
+++ b/chesshog-qrcode/src/main/java/org/hedgecode/chess/qrcode/zip/ZipContentUtils.java
@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2018-2019. Developed by Hedgecode.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.hedgecode.chess.qrcode.zip;
+
+import java.util.Arrays;
+import java.util.Base64;
+
+/**
+ *
+ *
+ * @author Dmitry Samoshin aka gotty
+ */
+public class ZipContentUtils {
+
+    private static final int LENGTH_BYTE_COUNT = 4;
+
+    private static final int MAX_CONTENT_LENGTH = 65536;
+
+    public static int getMaxContentLength() {
+        return MAX_CONTENT_LENGTH;
+    }
+
+    public static int getZipLength(byte[] zipBytes) {
+        return fromByteArray(
+                Arrays.copyOf(zipBytes, LENGTH_BYTE_COUNT)
+        );
+    }
+
+    public static byte[] getZipBytes(byte[] zipBytes) {
+        return Arrays.copyOfRange(
+                zipBytes, LENGTH_BYTE_COUNT, zipBytes.length
+        );
+    }
+
+    public static byte[] concat(int length, byte[] bytes) {
+        return concat(
+                toByteArray(length),
+                bytes
+        );
+    }
+
+    public static String base64Encode(byte[] bytes) {
+        return Base64.getEncoder().encodeToString(bytes);
+    }
+
+    public static byte[] base64Decode(String value) {
+        return Base64.getDecoder().decode(value);
+    }
+
+    private static byte[] toByteArray(int value) {
+        return new byte[] {
+                (byte) (value >> 24),
+                (byte) (value >> 16),
+                (byte) (value >> 8),
+                (byte) (value)
+        };
+    }
+
+    private static int fromByteArray(byte[] bytes) {
+        return bytes[0] << 24
+                | (bytes[1] & 0xFF) << 16
+                | (bytes[2] & 0xFF) << 8
+                | (bytes[3] & 0xFF);
+    }
+
+    private static byte[] concat(byte[]... byteArrays) {
+        int length = 0;
+        for (byte[] bytes : byteArrays) {
+            length += bytes.length;
+        }
+        byte[] concatBytes = new byte[length];
+        length = 0;
+        for (byte[] bytes : byteArrays) {
+            if (bytes.length == 0)
+                continue;
+            System.arraycopy(bytes, 0, concatBytes, length, bytes.length);
+            length += bytes.length;
+        }
+        return concatBytes;
+    }
+
+    private ZipContentUtils() {
+        throw new AssertionError(
+                "No org.hedgecode.chess.qrcode.zip.ZipContentUtils instances!"
+        );
+    }
+
+}