Add File

src/main/java/org/dromara/easyai/tools/IdCreator.java

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+package org.dromara.easyai.tools;
+
+public class IdCreator {
+    // 生成分布式全局唯一ID
+    public static final long sequenceBits = 12L;// 序列掩码位数
+    public static final long workBits = 4L;// 分布式机器号共四位
+    public static long workId = 1L;
+    public static final long workAndBusBites = workBits + sequenceBits;
+    private static final long sequenceMask = -1L ^ (-1L << sequenceBits);// 序列掩码极值
+    private static IdCreator AcceptorId = new IdCreator();
+    private static long sequence = 0L;
+    private static long lastTimestamp = -1L;
+
+    private IdCreator() {
+
+    }
+
+    public synchronized long nextId() {
+        long timestamp = timeGen();
+        if (timestamp < lastTimestamp) {
+            throw new RuntimeException(String.format(
+                    "Clock moved backwards.  Refusing to generate id for %d milliseconds", lastTimestamp - timestamp));
+        }
+        if (lastTimestamp == timestamp) {
+            sequence = (sequence + 1) & sequenceMask;
+            if (sequence == 0) {
+                timestamp = tilNextMillis(lastTimestamp);
+            }
+        } else {
+            sequence = 0L;
+        }
+        lastTimestamp = timestamp;
+        return (timestamp << workAndBusBites) | (sequence << workBits) | workId;
+
+    }
+
+    protected long tilNextMillis(long lastTimestamp) {
+        long timestamp = timeGen();
+        while (timestamp <= lastTimestamp) {
+            timestamp = timeGen();
+        }
+        return timestamp;
+    }
+
+    protected long timeGen() {
+        return System.currentTimeMillis();
+    }
+
+    public static IdCreator get() {
+        return AcceptorId;
+    }
+}