public class AjaxMessage implements Serializable {
      private String state;     private String msg;     private Object data;     public String getState() {
          return state;     }     public void setState(String state) {
          this.state = state;     }     public String getMsg() {
          return msg;     }     public void setMsg(String msg) {
          this.msg = msg;     }     public Object getData() {
          return data;     }     public void setData(Object data) {
          this.data = data;     }     public String toJson() {
          return JSON.toJSONString(this);     }     public static Builder SYS_ERR() {
          return new Builder(ResponseCode.SYS_ERR);     }     public static Builder SUCC() {
          return new Builder(ResponseCode.SUCC);     }     public static Builder ERR(ResponseCode responseCode) {
          return new Builder(responseCode);     }     public static Builder ERR(String state, String msg) {
          return new Builder(state, msg);     }     public static Builder ERR(String msg) {
          return new Builder("00001", msg);     }     public AjaxMessage(Builder builder) {
          this.state = builder.state;         this.msg = builder.msg;         this.data = builder.data;     }     public static class Builder {
          private String state;         private String msg;         private Object data;         public Builder(ResponseCode responseCode) {
              this.state = responseCode.getState();             this.msg = responseCode.getMsg();         }         public Builder(String state, String msg) {
              this.state = state;             this.msg = msg;         }         public Builder code(String state) {
              this.state = state;             return this;         }         public Builder message(String msg) {
              this.msg = msg;             return this;         }         public Builder data(Object data) {
              this.data = data;             return this;         }         public AjaxMessage build() {
              return new AjaxMessage(this);         }     } }