[update] SysUtil 增加JVM内存判断等待锁

Signed-off-by: 夜雪剑辰 <1107047387@qq.com>

src/main/java/com/yexuejc/base/util/SysUtil.java

@@ -3,7 +3,15 @@ package com.yexuejc.base.util;
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
 
 import java.net.URL;
+import java.text.DecimalFormat;
+import java.util.ArrayList;
+import java.util.List;
 import java.util.concurrent.*;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 
 /**
  * 系统工具类
@@ -14,6 +22,7 @@ import java.util.concurrent.*;
  * @date: 2017/12/28 16:12
  */
 public class SysUtil {
+    private static Logger logger = Logger.getLogger(SysUtil.class.getName());
     private static final String PROJECT_ROOT_PATH = "java.io.tmpdir";
 
     private SysUtil() {
@@ -79,4 +88,116 @@ public class SysUtil {
          */
         void execute();
     }
+
+
+    /**
+     * 获取当前JVM所有线程
+     *
+     * @return
+     */
+    public static List<Thread> getThreadList() {
+        List<Thread> threadList = new ArrayList<>();
+        ThreadGroup currentGroup = Thread.currentThread().getThreadGroup();
+        while (currentGroup.getParent() != null) {
+            currentGroup = currentGroup.getParent();
+        }
+        int activeCount = currentGroup.activeCount();
+        Thread[] threads = new Thread[activeCount];
+        currentGroup.enumerate(threads);
+        for (Thread thread : threads) {
+            threadList.add(thread);
+        }
+        return threadList;
+    }
+
+    /** 线程锁 */
+    private static final Lock THREAD_LOCK = new ReentrantLock();
+    /** 已经等待的时间 */
+    private static final AtomicInteger SLEEP_TIME = new AtomicInteger(0);
+    /** 最大等待3分钟 */
+    private static final int MAX_SLEEP_TIME = 180;
+
+    /**
+     * 通过锁的方式判断jvm的内存，如果超80%就等待（最大3分钟）JVM内存降低到80%再执行
+     */
+    public static void checkJvmMemory() {
+        THREAD_LOCK.lock();
+        try {
+            while (jvmMemoryIsNotExecutable()) {
+                //jvm内存使用率达到80%,阻塞所有线程，最大等待3分钟后放开
+                if (SLEEP_TIME.incrementAndGet() < MAX_SLEEP_TIME) {
+                    TimeUnit.SECONDS.sleep(1);
+                } else {
+                    break;
+                }
+            }
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+        } finally {
+            THREAD_LOCK.unlock();
+            SLEEP_TIME.set(0);
+        }
+    }
+
+    /**
+     * jvm内存是否大于80%（不能继续执行）
+     *
+     * @return true:是，false:不是
+     */
+    public static boolean jvmMemoryIsNotExecutable() {
+        Runtime runtime = Runtime.getRuntime();
+        //jvm总内存
+        long jvmTotalMemoryByte = runtime.totalMemory();
+        //jvm最大可申请
+        long jvmMaxMemoryByte = runtime.maxMemory();
+        //空闲空间
+        long freeMemoryByte = runtime.freeMemory();
+
+        double rate = (jvmTotalMemoryByte - freeMemoryByte) * 1.0 / jvmTotalMemoryByte;
+        if (rate >= 0.8) {
+            rate = (jvmTotalMemoryByte - freeMemoryByte) * 1.0 / jvmMaxMemoryByte;
+            if (rate >= 0.8) {
+                //jvm内存使用率达到80%
+                print(jvmTotalMemoryByte, jvmMaxMemoryByte, freeMemoryByte);
+                return true;
+            }
+        }
+        return false;
+    }
+
+    private static final DecimalFormat RATE_DECIMAL_FORMAT = new DecimalFormat("#.##%");
+
+    private static void print(long jvmTotalMemoryByte, long jvmMaxMemoryByte, long freeMemoryByte) {
+        if (logger.isLoggable(Level.WARNING)) {
+            String sb = "\n=========================================================" +
+                    "\nThread Name     = " + Thread.currentThread().getName() +
+                    "\nJVM Memory      = " + formatByte(jvmTotalMemoryByte) +
+                    "\nJVM Max Memory  = " + formatByte(jvmMaxMemoryByte) +
+                    "\nJVM Used Memory = " + formatByte(jvmTotalMemoryByte - freeMemoryByte) +
+                    "\nJVM Free Memory = " + formatByte(freeMemoryByte) +
+                    "\nJVM Memory Rate = " + RATE_DECIMAL_FORMAT.format((jvmTotalMemoryByte - freeMemoryByte) * 1.0 / jvmTotalMemoryByte) +
+                    "\n=========================================================";
+            logger.warning(sb);
+        }
+    }
+
+    private static String formatByte(long byteNumber) {
+        //换算单位
+        double format = 1024.0;
+        double kbNumber = byteNumber / format;
+        if (kbNumber < format) {
+            return new DecimalFormat("#.##KB").format(kbNumber);
+        }
+        double mbNumber = kbNumber / format;
+        if (mbNumber < format) {
+            return new DecimalFormat("#.##MB").format(mbNumber);
+        }
+        double gbNumber = mbNumber / format;
+        if (gbNumber < format) {
+            return new DecimalFormat("#.##GB").format(gbNumber);
+        }
+        double tbNumber = gbNumber / format;
+        return new DecimalFormat("#.##TB").format(tbNumber);
+    }
+
 }