快速构建一个权限项目

Posted 2021-03-13 My丶Ou

今天我们首先讲的是Json转化工具-JsonMapper开发:

在这里我们首先在pom文件引入jackson的两个依赖,分别是:

<!-- jackson -->
    <dependency>
      <groupId>org.codehaus.jackson</groupId>
      <artifactId>jackson-core-asl</artifactId>
      <version>1.9.13</version>
    </dependency>
    <dependency>
      <groupId>org.codehaus.jackson</groupId>
      <artifactId>jackson-mapper-asl</artifactId>
      <version>1.9.13</version>
    </dependency>

然后在util包编写JsonMapper类:

package cn.oyc.util;

import org.codehaus.jackson.map.DeserializationConfig;
import org.codehaus.jackson.map.ObjectMapper;
import org.codehaus.jackson.map.SerializationConfig;
import org.codehaus.jackson.map.annotate.JsonSerialize;
import org.codehaus.jackson.map.ser.impl.SimpleFilterProvider;
import org.codehaus.jackson.type.TypeReference;

public class JsonMapper {
    private static ObjectMapper objectMapper = new ObjectMapper();

    static{
        //config
        objectMapper.disable(DeserializationConfig.Feature.FAIL_ON_UNKNOWN_PROPERTIES);
        objectMapper.configure(SerializationConfig.Feature.FAIL_ON_EMPTY_BEANS,false);
        objectMapper.setFilters(new SimpleFilterProvider().setFailOnUnknownId(false));
        objectMapper.setSerializationInclusion(JsonSerialize.Inclusion.NON_EMPTY);
    }
    public static <T> String obj2String(T src){
        if (src==null){
            return null;
        }
        try {
            return src instanceof String ? (String) src : objectMapper.writeValueAsString(src);
        }catch (Exception e){
            e.printStackTrace();
            return null;
        }
    }
    public static <T> T string2Obj(String src, TypeReference<T> typeReference) {
        if (src == null || typeReference == null) {
            return null;
        }
        try {
            return (T) (typeReference.getType().equals(String.class) ? src : objectMapper.readValue(src, typeReference));
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
}

然后在学习我们的获取Spring上下文工具-ApplicationContextHelper开发

在common创建一个获取上下文的类applicationContextGelper:

package cn.oyc.common;

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;

@Component("applicationContextHelper")
public class ApplicationContextHelper implements ApplicationContextAware {
    private static ApplicationContext applicationContext;

    @Override
    public void setApplicationContext(ApplicationContext context) throws BeansException {
        applicationContext = context;
    }
    public static <T> T popBean(Class<T> clazz){
        if (applicationContext == null){
            return null;
        }
        return applicationContext.getBean(clazz);
    }

    public static <T> T popBean(String name,Class<T> clazz){
        if (applicationContext == null){
            return null;
        }
        return applicationContext.getBean(name,clazz);
    }
}

然后别忘记在spring-servle.xml配置一下,内容为:

<bean class="cn.oyc.common.ApplicationContextHelper" lazy-init="false" />

今天我们就教到这里,请关注下集!