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redis序列化问题

0

1

redis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

  @Override
    //单条查询
    public User findUserById(int userId) {
        ValueOperations<String, Object> vos = redisTemplate.opsForValue();

        User user = null;
        if ("".equals(vos.get(String.valueOf(userId)))){

//            (redisTemplate.opsForValue().get(String.valueOf(userId))==null)
            logger.info("\n从缓存返回空值");
            return user;
        }

        try {

            if (vos.get(String.valueOf(userId)) != null) {
                logger.info("\n" + "从缓存中查询单条数据");
                user = (User) vos.get(String.valueOf(userId));
            } else {
                logger.info("\n" + "从数据库中查询单条数据");
                user = userDao.findUserById(userId);
                if (user != null) {
                    vos.set(String.valueOf(userId), user);
                    logger.info("\n" + "新增单条缓存数据:" + vos.get(String.valueOf(userId)));
                } else {
                    vos.set(String.valueOf(userId),"", 60,TimeUnit.SECONDS);
                    logger.info("\n" + "将空值存到缓存");
                }
            }
        } catch (Throwable t) {
            t.printStackTrace();
        }
        return user;


    }

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用./shutdown.sh关闭rmi服务器的tomcat,然后启动客户端的错误

0

1

springRMI

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

java.rmi.ConnectException: Connection refused to host:127.0.0.1; nested exception is:
        java.net.ConnectException: Connection refused: connect
        at sun.rmi.transport.tcp.TCPEndpoint.newSocket(Unknown Source)
        at sun.rmi.transport.tcp.TCPChannel.createConnection(Unknown Source)
        at sun.rmi.transport.tcp.TCPChannel.newConnection(Unknown Source)
        at sun.rmi.server.UnicastRef.invoke(Unknown Source)
        at java.rmi.server.RemoteObjectInvocationHandler.invokeRemoteMethod
        (Unknown Source)
        at java.rmi.server.RemoteObjectInvocationHandler.invoke(Unknown Source)
        at $Proxy0.call(Unknown Source)
        at RMI.Client.callRMI(Client.java:39)
        at RMI.Client.main(Client.java:53)
        Caused by: java.net.ConnectException: Connection refused: connect
        at java.net.PlainSocketImpl.socketConnect(Native Method)
        at java.net.PlainSocketImpl.doConnect(Unknown Source)
        at java.net.PlainSocketImpl.connectToAddress(Unknown Source)
        at java.net.PlainSocketImpl.connect(Unknown Source)
        at java.net.SocksSocketImpl.connect(Unknown Source)
        at java.net.Socket.connect(Unknown Source)
        at java.net.Socket.connect(Unknown Source)
        at java.net.Socket.<init>(Unknown Source)
        at java.net.Socket.<init>(Unknown Source)
        at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket
        (Unknown Source)
        at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket
        (Unknown Source)
        ... 9 more

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maven里jar包该在怎么用，POM.XML的作用是什么

1

maven

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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shiro如何整合JWT

0

1

shiro

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

该问题已被官方收录

JWT工具类不知道引用一些什么依赖，需要怎么配置

0

1

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 源码

public class JwtHelper {
    private final static String base64Secret = "MDk4ZjZiY2Q0NjIxZDM3M2NhZGU0ZTgzMjYyN2I0ZjY=";
    private final static int expiresSecond = 172800000;
    
    public static Claims parseJWT(String jsonWebToken) {
        try {
            Claims claims = Jwts.parser()
                    .setSigningKey(DatatypeConverter.parseBase64Binary(base64Secret))
                    .parseClaimsJws(jsonWebToken).getBody();
            return claims;
        } catch (Exception ex) {
            return null;
        }
    }
    
    public static String createJWT(String username, String roles, String privileges) {
        SignatureAlgorithm signatureAlgorithm = SignatureAlgorithm.HS256;
        
        long nowMillis = System.currentTimeMillis();
        Date now = new Date(nowMillis);
        
        //生成签名密钥
        byte[] apiKeySecretBytes = DatatypeConverter.parseBase64Binary(base64Secret);
        Key signingKey = new SecretKeySpec(apiKeySecretBytes, signatureAlgorithm.getJcaName());
        
        //添加构成JWT的参数
        JwtBuilder builder = Jwts.builder().setHeaderParam("typ", "JWT")
                .claim("user_name", username)
                .claim("user_role", roles)
                .claim("user_privilege", privileges)
                .signWith(signatureAlgorithm, signingKey);
        //添加Token过期时间
        if (expiresSecond >= 0) {
            long expMillis = nowMillis + expiresSecond;
            Date exp = new Date(expMillis);
            builder.setExpiration(exp).setNotBefore(now);
        }
        
        //生成JWT
        return builder.compact();
    }
}

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映射文件中 sql语句全都出现标红运行却没问题

2

1

mybatis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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mybatis 查询全表时发生异常

0

1

mybatis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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自定义标签是如何实现时间的转换的

2

1

时间转换(C标签)

class="cursor-pointer"> 详细描述

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在spring boot中使用rmi报错

0

1

springboot

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

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自动生成不同的序列化UID

1

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

package test1;

import java.io.Serializable;

public class Animal implements Serializable {
//    private static final long serialVersionUID = 1L;
    private static String age = "222";
    private String kind;
    private String color;
    transient private String name;
//    private String master;
//
//    public String getMaster() {
//        return master;
//    }
//
//    public void setMaster(String master) {
//        this.master = master;
//    }


    @Override
    public String toString() {
        return "Animal{" +
                "kind='" + kind + '\'' +
                ", color='" + color + '\'' +
                ", name='" + name + '\'' +
                ", age='"+age+'\''+
//                ", master ='"+master+'\''+
                '}';
    }

    public static String getAge() {
        return age;
    }

    public static void setAge(String age) {
        Animal.age = age;
    }

    public String getKind() {
        return kind;
    }

    public void setKind(String kind) {
        this.kind = kind;
    }

    public String getColor() {
        return color;
    }

    public void setColor(String color) {
        this.color = color;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}



package test1;

import java.io.*;

public class Serialization {
    public static void main(String[] args) throws  Exception{
//        serializeAnimal();
        Animal animal2= deserializeAnimal();
        System.out.println("反序列化后得到的对象为："+animal2);



    }
    private static void serializeAnimal() throws IOException{
        //实例化对象和属性
        Animal animal1=new Animal();
        animal1.setColor("red");
        animal1.setKind("cat");
        animal1.setName("coco");
        // // ObjectOutputStream 对象输出流，对象存储到.txt 文件中，完成对象的序列化操作
        ObjectOutputStream oos=new ObjectOutputStream(new FileOutputStream("/Users/a1/test/animal.txt"));
        //writeObject(Object obj)方法可对参数指定的obj对象进行序列化，把得到的字节序列写到一个目标输出流中
        oos.writeObject(animal1);
        System.out.println("序列化Animal成功");
        System.out.println("进行序列化的对象为："+animal1);
        oos.close();
    }

    private static Animal deserializeAnimal() throws Exception{
        // ObjectInputStream 对象读取流
        ObjectInputStream ois=new ObjectInputStream(new FileInputStream("/Users/a1/test/animal.txt"));
        //readObject()方法从一个源输入流中读取字节序列，再把它们反序列化为一个对象，并将其返回。
        Animal animal2 = (Animal) ois.readObject();
        System.out.println("Animal对象反序列化成功！");
        return animal2;
    }
}