SpringMvc

@RequestParam 请求参数注解

属性值  value :表示请求参数名

            required：改参数是否必须，默认为false，如果设置为true，请求参数为必须

　　　defaultVale：默认值。

@Responsebody

响应对象必须为对像格式。响应参数转换为json格式，produces = MediaType.APPLICATION_JSON_UTF8_VALUE

这是一个通用实体类。

import java.util.function.Supplier;

/**
 * @param <T>
 * @author cutenaiad
 * @author peikun.wpk
 */
public class DataModel<T> {

    /**
     * 异常堆栈
     */
    private StackTraceElement[] errorTrace;
    /**
     * 给前端的提示信息
     */
    private String prompt;
    /**
     * true:成功,false:失败
     */
    private boolean success;
    /**
     * 分页+数据
     */
    private Pagination pagination;

    private T data;
    
    /**
     * 兼容 DataTable的分页
     */
    private Long recordsTotal;    
    private Long recordsFiltered;

    public DataModel() {
    }

    public DataModel(StackTraceElement[] errorTrace, String prompt, boolean success, Pagination pagination, T data) {
        this.errorTrace = errorTrace;
        this.prompt = prompt;
        this.success = success;
        this.pagination = pagination;
        this.data = data;
    }

    /**
     * 无分页构造函数
     *
     * @param errorTrace
     * @param prompt
     * @param success
     * @param data
     */
    public DataModel(StackTraceElement[] errorTrace, String prompt, boolean success, T data) {
        this.errorTrace = errorTrace;
        this.prompt = prompt;
        this.success = success;
        this.data = data;
    }

    /**
     * 成功且有结果集的DataModal,不支持分页
     *
     * @param data
     * @param <T>
     * @return
     */
    public static <T> DataModel<T> getSucDataModal(T data) {
        DataModel<T> d = new DataModel<T>(null, null, true, data);
        return d;
    }

    /**
     * 成功且有结果集的DataModal,支持分页
     *
     * @param data
     * @param <T>
     * @return
     */
    public static <T> DataModel<T> getSucDataModal(T data, Supplier<Pagination> paginationSupplier) {
        DataModel<T> d = new DataModel<T>(null, null, true, paginationSupplier.get(), data);
        return d;
    }

    /**
     * 成功但没有结果集的DataModal
     *
     * @param <T>
     * @return
     */
    public static <T> DataModel<T> getNotDataSucDataModal() {
        DataModel<T> d = new DataModel<T>(null, null, true, null);
        return d;
    }

    /**
     * 失败的DataModal
     *
     * @param prompt
     * @param errorTrace
     * @param <T>
     * @return
     */
    public static <T> DataModel<T> getFailDataModal(String prompt, StackTraceElement[] errorTrace) {
        DataModel<T> d = new DataModel<T>(errorTrace, prompt, false, null);
        return d;
    }

    /**
     * 失败的DataModal
     *
     * @param prompt
     * @param <T>
     * @return
     */
    public static <T> DataModel<T> getFailDataModalNotException(String prompt) {
        DataModel<T> d = new DataModel<T>(null, prompt, false, null);
        return d;
    }

    public StackTraceElement[] getErrorTrace() {
        return errorTrace;
    }

    public void setErrorTrace(StackTraceElement[] errorTrace) {
        this.errorTrace = errorTrace;
    }

    public String getPrompt() {
        return prompt;
    }

    public void setPrompt(String prompt) {
        this.prompt = prompt;
    }

    public boolean isSuccess() {
        return success;
    }

    public void setSuccess(boolean success) {
        this.success = success;
    }

    public Pagination getPagination() {
        return pagination;
    }

    public void setPagination(Pagination pagination) {
        this.pagination = pagination;
    }

    public T getData() {
        return data;
    }

    public void setData(T data) {
        this.data = data;
    }

   public Long getRecordsTotal() {
      return recordsTotal == null ? (pagination == null ? 0 : pagination.getTotalRows()) : recordsTotal;
   }

   public void setRecordsTotal(Long recordsTotal) {
      this.recordsTotal = recordsTotal;
   }

   public Long getRecordsFiltered() {
      return recordsFiltered == null ? (pagination == null ? 0 : pagination.getTotalRows()) : recordsFiltered;
   }

   public void setRecordsFiltered(Long recordsFiltered) {
      this.recordsFiltered = recordsFiltered;
   }
}