自定义异常BException

/**
 * 业务系统 RuntimeException 
* 业务异常， 需要对外抛错。
* 1. 接管异常信息
* 2. 单据信息与后台信息交互
* 3. 业务错误进行回滚
* 
* @author weilecai
*
*/
public class BException extends RuntimeException{
private static final long serialVersionUID = 1L;
private String msg;//错误消息
private boolean async; //是否异步

public BException(){
super();
}

public BException(String msg) {
super(msg);
this.async = false;
this.msg = msg;
}

public BException(Exception e){
super(e.getMessage());
this.async = false;
if(e instanceof BException){
BException self = (BException) e;
   this.msg = self.getMsg();
}else{
this.msg = e.getMessage();
}

}


public String getMsg() {
return msg;
}


public void setMsg(String msg) {
this.msg = msg;
}


public boolean isAsync() {
return async;
}


public void setAsync(boolean async) {
this.async = async;
}

public static BException E(String msg){
return new BException(msg);
} 
}