struts2显示图片

import java.io.ByteArrayOutputStream;
import java.io.IOException;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.opensymphony.xwork2.ActionContext;


public class TestDao {
private  ByteArrayOutputStream bout = new ByteArrayOutputStream(4096);
public String execute(){
HttpServletResponse response=(HttpServletResponse)ActionContext.getContext().get(org.apache.struts2.StrutsStatics.HTTP_RESPONSE);
try {

BarCoderTool barTool=new BarCoderTool();
bout=barTool.doGet((HttpServletRequest)ActionContext.getContext().get(org.apache.struts2.StrutsStatics.HTTP_REQUEST),(HttpServletResponse)ActionContext.getContext().get(org.apache.struts2.StrutsStatics.HTTP_RESPONSE));
  }catch (Exception e) {
// TODO Auto-generated catch block
//e.printStackTrace();
}
  response.setContentType("image/jpeg");
  try {
response.getOutputStream().write(bout.toByteArray());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
}