spring boot 枚举转换 博客分类： Java

1、所有枚举使用实现一个通用接口

例如：

public interface BaseEnum {
    Integer getCode() ;
    String getMessage() ;
}

枚举定义：

public enum SexType  implements  BaseEnum{
   MEN(1, "男"), WOMAN(2, "女"), NONE(0, "未知");
   private int code;
   private String text;
SexType(int code, String text) {
      this.code = code;
      this.text = text;
}

   public Integer getCode() {
      return code;
}

   public String getMessage() {
      return text;
}
}

 

2、定义枚举转换工厂

public class EnumConverterFactory  implements ConverterFactory<String,BaseEnum> {

    private static final Map<Class, Converter> converterMap = new WeakHashMap<>();
@Override
public <T extends BaseEnum> Converter<String, T> getConverter(Class<T> targetType) {
        Converter result = converterMap.get(targetType);
        if(result == null) {
            result = new ConverterToEnum<>(targetType);
converterMap.put(targetType, result);
}
        return result;
}
    class ConverterToEnum<T extends BaseEnum> implements Converter<String, T> {
        private final Class<T> enumType;
        private Map<String, T> enumMap = new HashMap<>();
        public ConverterToEnum(Class<T> enumType) {
            this.enumType = enumType;
T[] enums = enumType.getEnumConstants();
            for(T e : enums) {
                enumMap.put(e.getCode() + "", e);
}
        }


        @Override
public T convert(String source) {
            T result = enumMap.get(source);
            if(result == null) {
                throw new IllegalArgumentException("No element matches " + source);
}
            return result;
}
    }

}

 

4、注册到spring boot

import org.springframework.context.annotation.Configuration;
import org.springframework.format.FormatterRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
@Configuration
public class MyWebAppConfigurer extends WebMvcConfigurerAdapter {

    @Override
public void addFormatters(FormatterRegistry registry) {
        registry.addConverterFactory(new EnumConverterFactory());
}
}

 

 

5、spring boot json 响应code转换

import com.bjike.utils.EnumTools;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import org.apache.commons.lang3.math.NumberUtils;
import java.io.IOException;
@SuppressWarnings({ "rawtypes" })
public class EnumJsonSerializer extends JsonSerializer<Enum> {

   @Override
public void serialize(Enum value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
      if (null == value) {
         return;
}
      int code = NumberUtils.toInt(EnumTools.getInvokeValue(value, "getCode"));
      if (code == -1) {
         code = value.ordinal();
}
      gen.writeString(String.valueOf(code));
}

}

MyWebAppConfigurer 类中，新增实现方法

 

/**
 * 新增枚举转换器
 * json返回枚举数字
 * */
@Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
    Jackson2ObjectMapperBuilder builder = new Jackson2ObjectMapperBuilder();
builder.serializationInclusion(JsonInclude.Include.NON_NULL);
ObjectMapper objectMapper = builder.build();
SimpleModule simpleModule = new SimpleModule();
simpleModule.addSerializer(Enum.class, new EnumJsonSerializer());
objectMapper.registerModule(simpleModule);
objectMapper.configure(MapperFeature.PROPAGATE_TRANSIENT_MARKER, true);
converters.add(new MappingJackson2HttpMessageConverter(objectMapper));}

 

枚举反射类：EnumTools 

 

import org.apache.commons.lang3.math.NumberUtils;
import org.apache.commons.lang3.reflect.MethodUtils;

import java.lang.reflect.Method;
import java.util.*;

public class EnumTools {
   
   public static String getText(Class<?> ref , Object code){
      return parseEumn(ref).get( String.valueOf(code) ) ;
}

   public static <T> T parseToEumn(Class<T> ref , Integer data){

      if(data == null){return null;}

      T[] ts = ref.getEnumConstants() ;
      for(T t : ts){
         Enum<?> tempEnum = (Enum<?>) t ;
         int code = NumberUtils.toInt(getInvokeValue(t, "getCode") , -1);
         if(code == -1){
            code = tempEnum.ordinal() ;
}
         if(code == data){
            return t ;
}
      }
      return null ;
}
   
   public static <T> Map<String, String> parseEumn(Class<T> ref){
      Map<String, String> map = new LinkedHashMap<>() ;
      if(ref.isEnum()){
         T[] ts = ref.getEnumConstants() ; 
         for(T t : ts){
            String text = getInvokeValue(t, "getMessage") ;
Enum<?> tempEnum = (Enum<?>) t ;
            if(text == null){
               text = tempEnum.name() ;
}
            String code = getInvokeValue(t, "getCode") ; 
            if(code == null){
               code = String.valueOf( tempEnum.ordinal() );
}
            map.put(code , text ) ; 
}
      }
      return map ;
}
   
   public static <T> String getInvokeValue(T t , String methodName){
      try {
         Method method = MethodUtils.getAccessibleMethod( t.getClass() , methodName);
String text = String.valueOf(method.invoke( t )) ;
         return text ;
} catch (Exception e) {
         return null ;
}
   }

}