// eHatcher Solutions, Inc
import java.lang.reflect.*;
import java.io.*;
import java.net.URLEncoder;
import java.text.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
/**
* Base class for remote scripting servlets that use Microsoft's remote scripting (MSRS) or JavaScript remote scripting (JSRS).
*
* Usage:
* <pre>
* public class RSExample extends RemoteScriptingServlet {
* public static String getSubcategories (String catstr) throws Exception
* {
* String retval = "";
* // ... implementation details
* return retval;
* }
* }
* </pre>
*
* @version1.0 February 10, 2001
* @authorErik Hatcher
*/
abstract public class RemoteScriptingServlet extends HttpServlet {
boolean debugOn = false;
private final static int MSRS = 0;
private final static int JSRS = 1;
private int clientType;
/**
* Generates the appropriate response to either an MSRS or JSRS method invocation.
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws IOException, ServletException
{
// Requests look like this:
// MSRS: <servletname>?_method=method=execute=1=1
// JSRS: <servletname>?C=callback=method=[1]
debugOn = request.getParameter("debug") != null;
debug("-------");
boolean error = false;
String returnValue;
String callbackName = "";
// Everything is wrapped in a try/catch block, any exception will cause the ERROR return value
// so that the client side can deal with it gracefully
try {
String method;
int pcount = 0;
callbackName = request.getParameter("C");
if (callbackName != null) {
// client is JSRS - it passes a "C" parameter
clientType = JSRS;
method = request.getParameter("F");
// JSRS doesn't tell us how many parameters, so count them
while (request.getParameter("P" + pcount) != null)
pcount++;
}
else {
clientType = MSRS;
method = request.getParameter("_method");
pcount = Integer.parseInt(request.getParameter("pcount"));
}
debug("clientType = " + clientType);
debug("Method = " + method);
debug("pcount = " + pcount);
// build paramSpec array with all String class items
// build params array with the p0, p1, ...., pN request values
Class paramSpec[] = new Class[pcount];
Class stringClass = Class.forName("java.lang.String");
String params[] = new String[pcount];
if (pcount > 0) {
for (int i=0; i < pcount; i++) {
paramSpec[i] = stringClass;
params[i] = request.getParameter(( (clientType == MSRS) ? "p" : "P") + i);
if (clientType == JSRS) {
// JSRS sends parameters wrapped with brackets, strip them off
params[i] = params[i].substring(1, params[i].length() - 1);
}
debug("p" + i + " = " + params[i]);
}
}
// find and invoke the appropriate static method in the concrete class
Class c = this.getClass();
Method m = c.getMethod(method, paramSpec);
returnValue = (String) m.invoke(null, params);
} catch (Exception e) {
// if the invoked method threw an exception, pull it out of the wrapper exception that "invoke" throws
// so that the client gets the real error message
if (e instanceof InvocationTargetException) {
e = (Exception) ((InvocationTargetException)e).getTargetException();
}
debug("Oops, exception: " + e);
error = true;
returnValue = e.toString();
e.printStackTrace();
}
String outputString = "";
if (clientType == MSRS) {
// Build the appropriate MSRS response
// Microsoft's Remote Scripting has three types: SIMPLE, EVAL_OBJECT, and ERROR.
// Currently only SIMPLE and ERROR are supported.
outputString = "<METHOD VERSION=\"1.0.8044\"><RETURN_VALUE TYPE=" + (error ? "ERROR" : "SIMPLE") + ">" + encode(returnValue) + "</RETURN_VALUE></METHOD>";
}
else {
// Build the appropriate JSRS response
outputString = "<html><head></head><body onload=\"p=document.layers?parentLayer:window.parent;";
if (error) {
outputString += "p.jsrsError('" + callbackName + "','jsrsError: " + encode(returnValue) + "');\">jsrsError: " + jsrsErrorEscape(returnValue);
}
else {
outputString += "p.jsrsLoaded('" + callbackName + "');\">jsrsPayload:<br><form name=\"jsrs_Form\"><textarea name=\"jsrs_Payload\">" + jsrsEscape(returnValue) + "</textarea></form>";
}
outputString += "</body></html>";
}
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println(outputString);
}
private void debug (String str)
{
if (debugOn) System.out.println("[RemoteScriptingServlet] " + str);
}
public static String jsrsEscape (String str)
{
StringBuffer sb = new StringBuffer(str);
// probably an easier way to do this, but this will do for now
for (int i = 0; i < sb.length(); i++) {
if (sb.charAt(i) == '/') {
sb.replace(i,i+1,"\\/");
i += 2;
}
}
return new String(sb);
}
public static String jsrsErrorEscape (String str)
{
StringBuffer sb = new StringBuffer(str);
// probably an easier way to do this, but this will do for now
for (int i = 0; i < sb.length(); i++) {
if (sb.charAt(i) == '\'') {
sb.replace(i,i+1,"\\'");
i += 2;
}
if (sb.charAt(i) == '\"') {
sb.replace(i,i+1,"\\\"");
i += 2;
}
}
return new String(sb);
}
public static String encode (String str)
{
// but URLEncoder.encode isn't enough... '+' should really be "%20"
StringBuffer sb = new StringBuffer(URLEncoder.encode(str));
for (int i = 0; i < sb.length(); i++) {
if (sb.charAt(i) == '+') {
sb.replace(i,i+1,"%20");
i += 2;
}
}
return new String(sb);
}
/*
MSRS return details:
String return:
<METHOD VERSION="1.0.8044"><RETURN_VALUE TYPE=SIMPLE>%3CMessages%3E%3CMsg7%20ID%3D%221%22%3EMsg7%20data%3C/Msg7%3E%3C/Messages%3E</RETURN_VALUE></METHOD>
Error return:
<METHOD VERSION="1.0.8044"><RETURN_VALUE TYPE=ERROR>xyz%20%3A%20not%20a%20public%20function</RETURN_VALUE></METHOD>
*/
/*
JSRS return details:
Successful JSRS return:
<html><head></head><body onload="p=document.layers?parentLayer:window.parent;p.jsrsLoaded('jsrs1');">jsrsPayload:<br><form name="jsrs_Form"><textarea name="jsrs_Payload">string~TEST</textarea></form></body></html>
Error JSRS return:
<html><head></head><body onload="p=document.layers?parentLayer:window.parent;p.jsrsError('jsrs1','error');">error</body></html>
*/
}
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