envservlet.java

java xml开发指南（初学者推荐）Java Xml 编程指南书籍源码

package MyNa.utils;
// servlet class EnvServlet, which provides a few
// environment functions so that servlet classes
// which extend it can conveniently set environment
// values from an environment, initparameters, or
// explicit default strings, adding a prefix (often
// a filepath) if required

import javax.servlet.*;  // communicate with client
import javax.servlet.http.*; 

import MyNa.utils.Env;   // basic package

public class EnvServlet extends HttpServlet { 

public String setStr(Env E,String resNm,String pre,String nm,String dflt){
  //sets E[resNm] to pre+(getInitParameter(nm) or E[nm] or dflt)
  String val=getInitParameter(nm);
  if(null==val)val=E.getStr(nm);
  if(null==val)val=dflt;
  E.put(resNm,pre+val);
  return pre+val;
}
public String setStr(Env E,String nm,String pre,String dflt){
  //sets E[nm] to pre+(getInitParameter(nm) or E[nm] or dflt)
  return setStr(E,nm,pre,nm,dflt);
}

}