package cn.home1.oss.lib.webmvc.api;
   
   import static org.apache.commons.lang3.StringUtils.isNotBlank;
   
   import cn.home1.oss.lib.common.Jackson2Utils;
   
   import com.fasterxml.jackson.databind.ObjectMapper;
   
   import lombok.extern.slf4j.Slf4j;
  
  import java.util.function.Function;
  
  /**
   * Created by zhanghaolun on 16/10/29.
   */
  @Slf4j
  public class JsonToken<T> implements TypeSafeToken<T> {
  
    private final Function<String, T> fromToken;
    private final Function<T, String> toToken;
  
    public JsonToken( //
      final Class<T> type, //
      final ObjectMapper objectMapper //
    ) {
      this.toToken = Jackson2Utils.toJson(objectMapper);
      this.fromToken = Jackson2Utils.fromJson(objectMapper, type);
    }
  
    @Override
    public String toToken(final T obj) {
      return this.toToken != null && obj != null ? //
        this.toToken.apply(obj) : //
        (obj != null) ? obj.toString() : null;
    }
  
    @Override
    public T fromToken(final String token) {
      T result;
      try {
        result = isNotBlank(token) ? this.fromToken.apply(token) : null;
      } catch (final Exception ex) {
        log.warn("error reading token: {}", token, ex);
        result = null;
      }
      return result;
    }
  }