working transaction list retrieval

[mobile-ledger.git] / app / src / main / java / net / ktnx / mobileledger / utils / Digest.java

diff --git a/app/src/main/java/net/ktnx/mobileledger/utils/Digest.java b/app/src/main/java/net/ktnx/mobileledger/utils/Digest.java
new file mode 100644 (file)
index 0000000..c25ca59
--- /dev/null
+++ b/app/src/main/java/net/ktnx/mobileledger/utils/Digest.java
@@ -0,0 +1,89 @@
+/*
+ * Copyright © 2018 Damyan Ivanov.
+ * This file is part of Mobile-Ledger.
+ * Mobile-Ledger is free software: you can distribute it and/or modify it
+ * under the term of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your opinion), any later version.
+ *
+ * Mobile-Ledger is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License terms for details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Mobile-Ledger. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package net.ktnx.mobileledger.utils;
+
+import java.nio.ByteBuffer;
+import java.security.DigestException;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
+public class Digest {
+    private MessageDigest digest;
+    public Digest(String type) throws NoSuchAlgorithmException {
+        digest = MessageDigest.getInstance(type);
+    }
+    public static char[] hexDigitsFor(byte x) {
+        return hexDigitsFor((int) ((x<0) ? 256+x : x));
+    }
+    public static char[] hexDigitsFor(int x) {
+        if ((x < 0) || (x > 255)) throw new ArithmeticException(
+                String.format("Hex digits must be between 0 and 255 (argument: %d)", x));
+        char[] result = new char[]{0, 0};
+        result[0] = hexDigitFor(x / 16);
+        result[1] = hexDigitFor(x % 16);
+
+        return result;
+    }
+    public static char hexDigitFor(int x) {
+        if (x < 0) throw new ArithmeticException(
+                String.format("Hex digits can't be negative (argument: %d)", x));
+        if (x < 10) return (char) ('0' + x);
+        if (x < 16) return (char) ('a' + x - 10);
+        throw new ArithmeticException(
+                String.format("Hex digits can't be greater than 15 (argument: %d)", x));
+    }
+    public void update(byte input) {
+        digest.update(input);
+    }
+    public void update(byte[] input, int offset, int len) {
+        digest.update(input, offset, len);
+    }
+    public void update(byte[] input) {
+        digest.update(input);
+    }
+    public void update(ByteBuffer input) {
+        digest.update(input);
+    }
+    public byte[] digest() {
+        return digest.digest();
+    }
+    public int digest(byte[] buf, int offset, int len) throws DigestException {
+        return digest.digest(buf, offset, len);
+    }
+    public byte[] digest(byte[] input) {
+        return digest.digest(input);
+    }
+    public String digestToHexString() {
+        byte[] digest = digest();
+        StringBuilder result = new StringBuilder();
+        for (int i = 0; i < getDigestLength(); i++) {
+            result.append(hexDigitsFor(digest[i]));
+        }
+        return result.toString();
+    }
+    public void reset() {
+        digest.reset();
+    }
+    public int getDigestLength() {
+        return digest.getDigestLength();
+    }
+    @Override
+    public Object clone() throws CloneNotSupportedException {
+        return digest.clone();
+    }
+}