Convert project to gradle

1 files changed, 200 insertions, 0 deletions

diff --git a/src/main/java/org/traccar/helper/Checksum.java b/src/main/java/org/traccar/helper/Checksum.java
new file mode 100644
index 000000000..adfa697c5
--- /dev/null
+++ b/src/main/java/org/traccar/helper/Checksum.java
@@ -0,0 +1,200 @@
+/*
+ * Copyright 2012 - 2018 Anton Tananaev (anton@traccar.org)
+ *
+ * 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.traccar.helper;
+
+import java.nio.ByteBuffer;
+import java.nio.charset.StandardCharsets;
+import java.util.zip.CRC32;
+
+public final class Checksum {
+
+    private Checksum() {
+    }
+
+    public static class Algorithm {
+
+        private int poly;
+        private int init;
+        private boolean refIn;
+        private boolean refOut;
+        private int xorOut;
+        private int[] table;
+
+        public Algorithm(int bits, int poly, int init, boolean refIn, boolean refOut, int xorOut) {
+            this.poly = poly;
+            this.init = init;
+            this.refIn = refIn;
+            this.refOut = refOut;
+            this.xorOut = xorOut;
+            this.table = bits == 8 ? initTable8() : initTable16();
+        }
+
+        private int[] initTable8() {
+            int[] table = new int[256];
+            int crc;
+            for (int i = 0; i < 256; i++) {
+                crc = i;
+                for (int j = 0; j < 8; j++) {
+                    boolean bit = (crc & 0x80) != 0;
+                    crc <<= 1;
+                    if (bit) {
+                        crc ^= poly;
+                    }
+                }
+                table[i] = crc & 0xFF;
+            }
+            return table;
+        }
+
+        private int[] initTable16() {
+            int[] table = new int[256];
+            int crc;
+            for (int i = 0; i < 256; i++) {
+                crc = i << 8;
+                for (int j = 0; j < 8; j++) {
+                    boolean bit = (crc & 0x8000) != 0;
+                    crc <<= 1;
+                    if (bit) {
+                        crc ^= poly;
+                    }
+                }
+                table[i] = crc & 0xFFFF;
+            }
+            return table;
+        }
+
+    }
+
+    private static int reverse(int value, int bits) {
+        int result = 0;
+        for (int i = 0; i < bits; i++) {
+            result = (result << 1) | (value & 1);
+            value >>= 1;
+        }
+        return result;
+    }
+
+    public static int crc8(Algorithm algorithm, ByteBuffer buf) {
+        int crc = algorithm.init;
+        while (buf.hasRemaining()) {
+            int b = buf.get() & 0xFF;
+            if (algorithm.refIn) {
+                b = reverse(b, 8);
+            }
+            crc = algorithm.table[(crc & 0xFF) ^ b];
+        }
+        if (algorithm.refOut) {
+            crc = reverse(crc, 8);
+        }
+        return (crc ^ algorithm.xorOut) & 0xFF;
+    }
+
+    public static int crc16(Algorithm algorithm, ByteBuffer buf) {
+        int crc = algorithm.init;
+        while (buf.hasRemaining()) {
+            int b = buf.get() & 0xFF;
+            if (algorithm.refIn) {
+                b = reverse(b, 8);
+            }
+            crc = (crc << 8) ^ algorithm.table[((crc >> 8) & 0xFF) ^ b];
+        }
+        if (algorithm.refOut) {
+            crc = reverse(crc, 16);
+        }
+        return (crc ^ algorithm.xorOut) & 0xFFFF;
+    }
+
+    public static final Algorithm CRC8_EGTS = new Algorithm(8, 0x31, 0xFF, false, false, 0x00);
+    public static final Algorithm CRC8_ROHC = new Algorithm(8, 0x07, 0xFF, true, true, 0x00);
+
+    public static final Algorithm CRC16_IBM = new Algorithm(16, 0x8005, 0x0000, true, true, 0x0000);
+    public static final Algorithm CRC16_X25 = new Algorithm(16, 0x1021, 0xFFFF, true, true, 0xFFFF);
+    public static final Algorithm CRC16_MODBUS = new Algorithm(16, 0x8005, 0xFFFF, true, true, 0x0000);
+    public static final Algorithm CRC16_CCITT_FALSE = new Algorithm(16, 0x1021, 0xFFFF, false, false, 0x0000);
+    public static final Algorithm CRC16_KERMIT = new Algorithm(16, 0x1021, 0x0000, true, true, 0x0000);
+    public static final Algorithm CRC16_XMODEM = new Algorithm(16, 0x1021, 0x0000, false, false, 0x0000);
+
+    public static int crc32(ByteBuffer buf) {
+        CRC32 checksum = new CRC32();
+        while (buf.hasRemaining()) {
+            checksum.update(buf.get());
+        }
+        return (int) checksum.getValue();
+    }
+
+    public static int xor(ByteBuffer buf) {
+        int checksum = 0;
+        while (buf.hasRemaining()) {
+            checksum ^= buf.get();
+        }
+        return checksum;
+    }
+
+    public static int xor(String string) {
+        byte checksum = 0;
+        for (byte b : string.getBytes(StandardCharsets.US_ASCII)) {
+            checksum ^= b;
+        }
+        return checksum;
+    }
+
+    public static String nmea(String msg) {
+        int checksum = 0;
+        byte[] bytes = msg.getBytes(StandardCharsets.US_ASCII);
+        for (int i = 1; i < bytes.length; i++) {
+            checksum ^= bytes[i];
+        }
+        return String.format("*%02x", checksum).toUpperCase();
+    }
+
+    public static int sum(ByteBuffer buf) {
+        byte checksum = 0;
+        while (buf.hasRemaining()) {
+            checksum += buf.get();
+        }
+        return checksum;
+    }
+
+    public static String sum(String msg) {
+        byte checksum = 0;
+        for (byte b : msg.getBytes(StandardCharsets.US_ASCII)) {
+            checksum += b;
+        }
+        return String.format("%02X", checksum).toUpperCase();
+    }
+
+    public static long luhn(long imei) {
+        long checksum = 0;
+        long remain = imei;
+
+        for (int i = 0; remain != 0; i++) {
+            long digit = remain % 10;
+
+            if (i % 2 == 0) {
+                digit *= 2;
+                if (digit >= 10) {
+                    digit = 1 + (digit % 10);
+                }
+            }
+
+            checksum += digit;
+            remain /= 10;
+        }
+
+        return (10 - (checksum % 10)) % 10;
+    }
+
+}