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<% _abstractJSPBean.setRequest(request); %>
<% _abstractJSPBean.setResponse(response); %>
<% _abstractJSPBean.setServlet(this); %>

<% _abstractJSPBean.process(); %>

package lbm.jsputil;
import java.util.*;
import javax.servlet.http.*;
import javax.servlet.*;
public abstract class AbstractJSPBean {
  /* constants used for _state */
  public static final int NEW = 0;
  public static final int FIRSTPASS = 1;
  public static final int PROC = 2;
  public static final int ERR = -1;
  private int _state; // current state
  private String _errorMsg; // current message that is being appended during validation
  private boolean _skipPageOutput; // should the page output be skipped
  private SharedSessionBean _sharedSessionBean; // used for associating the JSP Bean with the HTTP Session
  /* standard Servlet objects that need to be setup for each JSP Bean */
  protected HttpServletRequest _request;
  protected HttpServletResponse _response;
  protected Servlet _servlet;
  public AbstractJSPBean () {
    setState(NEW);
  }
  protected abstract void beanProcess() throws java.io.IOException;
  protected abstract void beanFirstPassProcess() throws java.io.IOException;
  protected abstract void beanFooterProcess() throws java.io.IOException;
  protected abstract String getJSPCode();
  public void process() throws java.io.IOException {
    setSkipPageOutput(false); // by default do not skip page output. Specific bean process
                              // methods can override it.
    if (getState() == NEW) {
      setState(FIRSTPASS);
      beanFirstPassProcess();
    } else {
      resetErrorMsg();
      setState(PROC);
      beanProcess();
    }
    // validation that all common fields have been properly set by the application
    // this is actually checking that the code has been written properly
    String l_err = "";
    if (_sharedSessionBean == null) l_err = l_err + "; SharedSessionBean must be set";
    if (_request == null) l_err = l_err + "; Request must be set";
    if (_response == null) l_err = l_err + "; Response must be set";
    if (_servlet == null) l_err = l_err + "; Servlet must be set";
    if ( ! l_err.equals("")) throw new IllegalStateException(l_err);
  }
  public void footerProcess() throws java.io.IOException {
    beanFooterProcess();
  }
  protected void addErrorMsg (String addErrorMsg) {
    if (_errorMsg == null) _errorMsg = addErrorMsg;
    else _errorMsg =  _errorMsg + " <br>\n" + addErrorMsg;
    setState(ERR);
  }
  protected void resetErrorMsg () {
    _errorMsg = null;
  }
  public String getErrorMsg () {
    if (_errorMsg == null) return "";
    else return _errorMsg;
  }
  protected void setState (int newState) {
    _state = newState;
  }
  public int getState () {
    return _state;
  }
  public void setSharedSessionBean (SharedSessionBean newSharedSessionBean) {
    if (_sharedSessionBean == null) {
      _sharedSessionBean = newSharedSessionBean;
      _sharedSessionBean.putJSPBean(getJSPCode(), this);
    } else {
      if (_sharedSessionBean != newSharedSessionBean) {
        throw new IllegalStateException("SharedSessionBean is not set properly. SharedSessionBean must be the same for all PageBeans within the session");
      }
    }
  }
  public SharedSessionBean getSharedSessionBean () {
    return _sharedSessionBean;
  }
  public void setSkipPageOutput (boolean newSipPageOutput) {
    _skipPageOutput = newSipPageOutput;
  }
  public boolean getSkipPageOutput () {
    return _skipPageOutput;
  }
  protected void redirect (String redirectURL) throws java.io.IOException {
    // skip the page output since we are redirecting
    setSkipPageOutput(true);
    _response.sendRedirect(redirectURL);
  }
  public void setRequest (HttpServletRequest newRequest) {
    _request = newRequest;
  }
  public void setResponse (HttpServletResponse newResponse) {
    _response = newResponse;
  }
  public void setServlet (Servlet newServlet) {
    _servlet = newServlet;
  }
}