sun.misc.Unsafe.park(Native Method)异常

sun.misc.Unsafe.park(Native Method)异常，异常如下：

2019/07/30-09:40:34 [localhost-startStop-1] WARN org.apache.catalina.loader.WebappClassLoaderBase - The web application [iot-ms] appears to have started a thread named [HikariPool-1 housekeeper] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
sun.misc.Unsafe.park(Native Method)
java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1093)
java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:809)java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1074)java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1134)java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
java.lang.Thread.run(Thread.java:748)
2019/07/30-09:40:34 [localhost-startStop-1] WARN org.apache.catalina.loader.WebappClassLoaderBase - The web application [iot-ms] appears to have started a thread named [lettuce-eventExecutorLoop-2-1] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
sun.misc.Unsafe.park(Native Method)
java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)
java.util.concurrent.LinkedBlockingQueue.poll(LinkedBlockingQueue.java:467)
io.netty.util.concurrent.SingleThreadEventExecutor.takeTask(SingleThreadEventExecutor.java:251)
io.netty.util.concurrent.DefaultEventExecutor.run(DefaultEventExecutor.java:64)
io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:905)
io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
java.lang.Thread.run(Thread.java:748)

1.错误分析
这种情况有可能是在启动的时候，某个东西重复被初始化，导致内存溢出或者其它。分析找到错误的地方如下：

那么这里会有什么问题呢？
1、访问的路由重复
2、接收数据对象PostDeviceCommandOutDTO2接收数据初始化错误。
初步排除1的可能性，那么只能是2的原因了，那么我们一起来看一下这个对象里面有什么?

package com.iotplatform.client.dto;

import com.fasterxml.jackson.databind.node.ObjectNode;

public class PostDeviceCommandOutDTO2 {
    private String commandId;
    private String appId;
    private String deviceId;
    private CommandDTOV4 command;
    private String callbackUrl;
    private Integer expireTime;
    private String status;
    private ObjectNode result;
    private String creationTime;
    private String executeTime;
    private String platformIssuedTime;
    private String deliveredTime;
    private Integer issuedTimes;
    private Integer maxRetransmit;

    public PostDeviceCommandOutDTO2() {
    }

    public String getCommandId() {
        return this.commandId;
    }

    public void setCommandId(String commandId) {
        this.commandId = commandId;
    }

    public String getAppId() {
        return this.appId;
    }

    public void setAppId(String appId) {
        this.appId = appId;
    }

    public String getDeviceId() {
        return this.deviceId;
    }

    public void setDeviceId(String deviceId) {
        this.deviceId = deviceId;
    }

    public CommandDTOV4 getCommand() {
        return this.command;
    }

    public void setCommand(CommandDTOV4 command) {
        this.command = command;
    }

    public String getCallbackUrl() {
        return this.callbackUrl;
    }

    public void setCallbackUrl(String callbackUrl) {
        this.callbackUrl = callbackUrl;
    }

    public Integer getExpireTime() {
        return this.expireTime;
    }

    public void setExpireTime(Integer expireTime) {
        this.expireTime = expireTime;
    }

    public String getStatus() {
        return this.status;
    }

    public void setStatus(String status) {
        this.status = status;
    }

    public ObjectNode getResult() {
        return this.result;
    }

    public void setResult(ObjectNode result) {
        this.result = result;
    }

    public String getCreationTime() {
        return this.creationTime;
    }

    public void setCreationTime(String creationTime) {
        this.creationTime = creationTime;
    }

    public String getExecuteTime() {
        return this.executeTime;
    }

    public void setExecuteTime(String executeTime) {
        this.executeTime = executeTime;
    }

    public String getPlatformIssuedTime() {
        return this.platformIssuedTime;
    }

    public void setPlatformIssuedTime(String platformIssuedTime) {
        this.platformIssuedTime = platformIssuedTime;
    }

    public String getDeliveredTime() {
        return this.deliveredTime;
    }

    public void setDeliveredTime(String deliveredTime) {
        this.deliveredTime = deliveredTime;
    }

    public Integer getIssuedTimes() {
        return this.issuedTimes;
    }

    public void setIssuedTimes(Integer issuedTimes) {
        this.issuedTimes = issuedTimes;
    }

    public Integer getMaxRetransmit() {
        return this.maxRetransmit;
    }

    public void setMaxRetransmit(Integer maxRetransmit) {
        this.maxRetransmit = maxRetransmit;
    }

    public String toString() {
        return "PostDeviceCommandOutDTO2 [commandId=" + this.commandId + ", appId=" + this.appId + ", deviceId=" + this.deviceId + ", command=" + this.command + ", callbackUrl=" + this.callbackUrl + ", expireTime=" + this.expireTime + ", status=" + this.status + ", result=" + this.result + ", creationTime=" + this.creationTime + ", executeTime=" + this.executeTime + ", platformIssuedTime=" + this.platformIssuedTime + ", deliveredTime=" + this.deliveredTime + ", issuedTimes=" + this.issuedTimes + ",  maxRetransmit=" + this.maxRetransmit + "]";
    }
}

可以看出来这就是个简单的bean，没有什么特别的，但是你会发现

ObjectNode这个对象不能够序列化，在初始化的时候，不断去初始化这个对象，导致内存溢出，线程暴露出不安全，到此完美解决。