public Class NetServlet

private void displayCurrentStatus(LocalizedResource localUtil, String returnMessage, PrintWriter out)

Display the current Network server status

Parameters

localUtil:LocalizedResource: LocalizedResource to use for localizing messages
returnMessage:String: localized continue message for continue button on error form
out:PrintWriter: Form PrintWriter

doGet back to summary

doGet	back to summary
public synchronized void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException Overrides javax.servlet.http.HttpServlet.doGet. Get the form of NetServlet. Provides buttons and forms to control the Network server. Parameters request:HttpServletRequest Doc from javax.servlet.http.HttpServlet.doGet. an `HttpServletRequest` object that contains the request the client has made of the servlet response:HttpServletResponse Doc from javax.servlet.http.HttpServlet.doGet. an `HttpServletResponse` object that contains the response the servlet sends to the client Exceptions ServletException: Doc from javax.servlet.http.HttpServlet.doGet. if the request for the GET could not be handled IOException: Doc from javax.servlet.http.HttpServlet.doGet. if an input or output error is detected when the servlet handles the GET request

public synchronized void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException

Overrides javax.servlet.http.HttpServlet.doGet.

Get the form of NetServlet. Provides buttons and forms to control the Network server.

Parameters

request:HttpServletRequest

an HttpServletRequest object that contains the request the client has made of the servlet

response:HttpServletResponse

an HttpServletResponse object that contains the response the servlet sends to the client

Exceptions

ServletException:

if the request for the GET could not be handled

IOException:

if an input or output error is detected when the servlet handles the GET request

doPost back to summary

doPost	back to summary
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException Overrides javax.servlet.http.HttpServlet.doPost. Get the form of NetServlet. Provides a buttons and form to control the Network server Parameters request:HttpServletRequest Doc from javax.servlet.http.HttpServlet.doPost. an `HttpServletRequest` object that contains the request the client has made of the servlet response:HttpServletResponse Doc from javax.servlet.http.HttpServlet.doPost. an `HttpServletResponse` object that contains the response the servlet sends to the client Exceptions ServletException: Doc from javax.servlet.http.HttpServlet.doPost. if the request for the POST could not be handled IOException: Doc from javax.servlet.http.HttpServlet.doPost. if an input or output error is detected when the servlet handles the request

public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException

Overrides javax.servlet.http.HttpServlet.doPost.

Get the form of NetServlet. Provides a buttons and form to control the Network server

Parameters

request:HttpServletRequest

an HttpServletRequest object that contains the request the client has made of the servlet

response:HttpServletResponse

an HttpServletResponse object that contains the response the servlet sends to the client

Exceptions

ServletException:

if the request for the POST could not be handled

IOException:

if an input or output error is detected when the servlet handles the request

escapeHTML	back to summary
private String escapeHTML(String str) Escapes potentially dangerous characters in data written to the browser. Note This is a poor mans implementation - it doesn't protect against all kinds of attacks, and it cannot be used in all contexts. Parameters str:String the string to escape Returns:String A sanitized string.

escapeHTML

private String escapeHTML(String str)

Escapes potentially dangerous characters in data written to the browser.

Note

This is a poor mans implementation - it doesn't protect against all kinds of attacks, and it cannot be used in all contexts.

Parameters

str:String: the string to escape

Returns:String

A sanitized string.

escapeSingleQuotes	back to summary
private String escapeSingleQuotes(String str) If the received string has one or more single quotes in it, replace each one with the HTML escape-code for a single quote (apostrophe) so that the string can be properly displayed on a submit button. Parameters str:String The string in which we want to escape single quotes.

escapeSingleQuotes

private String escapeSingleQuotes(String str)

If the received string has one or more single quotes in it, replace each one with the HTML escape-code for a single quote (apostrophe) so that the string can be properly displayed on a submit button.

Parameters

str:String: The string in which we want to escape single quotes.

fixLanguageCode	back to summary
private String fixLanguageCode(String lang) Fix the language code, as some browsers send then in a bad format (for instance, Firefox sends en-us instead of en_US). Parameters lang:String language to be fixed Returns:String fixed version of the language, with _ separating parts and country in upper case

fixLanguageCode

private String fixLanguageCode(String lang)

Fix the language code, as some browsers send then in a bad format (for instance, Firefox sends en-us instead of en_US).

Parameters

lang:String: language to be fixed

Returns:String

fixed version of the language, with _ separating parts and country in upper case

fixLanguageCode	back to summary
private String fixLanguageCode(String lang, int index)

getCurrentAppUI	back to summary
private LocalizedResource getCurrentAppUI(HttpServletRequest request, String[] locale) Determine the locale file needed for this browsers preferences Defaults to the settings for derby.locale and derby.codeset if set English otherwise if browsers preferences can't be found Parameters request:HttpServletRequest HttpServetRequest for forms locale:String[] Name of locale (return arg) Returns:LocalizedResource the appUI which fits the browsers preferences

getCurrentAppUI

private LocalizedResource getCurrentAppUI(HttpServletRequest request, String[] locale)

Determine the locale file needed for this browsers preferences Defaults to the settings for derby.locale and derby.codeset if set English otherwise if browsers preferences can't be found

Parameters

request:HttpServletRequest: HttpServetRequest for forms
locale:String[]: Name of locale (return arg)

Returns:LocalizedResource

the appUI which fits the browsers preferences

getDoAction	back to summary
private String getDoAction(HttpServletRequest request) throws IOException

getForm	back to summary
private String getForm(HttpServletRequest request) throws IOException

getHtmlLabelledMessageInstance	back to summary
private String getHtmlLabelledMessageInstance(LocalizedResource localUtil, String key, String id) get an HTML labelled message from the resource bundle file, according to the given key.

getIntParameter	back to summary
private int getIntParameter(HttpServletRequest request, String name, String fieldKey, LocalizedResource localUtil, String returnMessage, PrintWriter out) Get an integer parameter Parameters request:HttpServletRequest HttpServetRequest for forms name:String parameter name fieldKey:String Key for the name of the field we're reading. localUtil:LocalizedResource LocalizedResource to use in localizing messages returnMessage:String localized continue message for continue button on error form out:PrintWriter Form PrintWriter

getIntParameter

private int getIntParameter(HttpServletRequest request, String name, String fieldKey, LocalizedResource localUtil, String returnMessage, PrintWriter out)

Get an integer parameter

Parameters

request:HttpServletRequest: HttpServetRequest for forms
name:String: parameter name
fieldKey:String: Key for the name of the field we're reading.
localUtil:LocalizedResource: LocalizedResource to use in localizing messages
returnMessage:String: localized continue message for continue button on error form
out:PrintWriter: Form PrintWriter

getLocStringFromLanguage	back to summary
private String getLocStringFromLanguage(String lang) Get locale string from language which may have qvalue set Parameters lang:String language string to parse Returns:String stripped language string to use in matching

getLocStringFromLanguage

private String getLocStringFromLanguage(String lang)

Get locale string from language which may have qvalue set

Parameters

lang:String: language string to parse

Returns:String

stripped language string to use in matching

getLogging	back to summary
private String getLogging(HttpServletRequest request) throws IOException

getParam	back to summary
private String getParam(HttpServletRequest request, String paramName) throws IOException get UTF8 parameter value and decode international characters Parameters request:HttpServletRequest HttpServletRequest paramName:String Parameter name Returns:String decoded String

getParam

private String getParam(HttpServletRequest request, String paramName) throws IOException

get UTF8 parameter value and decode international characters

Parameters

request:HttpServletRequest: HttpServletRequest
paramName:String: Parameter name

Returns:String

decoded String

getServerStatus	back to summary
private boolean getServerStatus() Get the currrent server status by using test connection Returns:boolean true if server is up and reachable; false; otherwise

getServerStatus

private boolean getServerStatus()

Get the currrent server status by using test connection

Returns:boolean: true if server is up and reachable; false; otherwise

getTrace	back to summary
private String getTrace(HttpServletRequest request) throws IOException

init back to summary

init	back to summary
public void init(ServletConfig config) throws ServletException Overrides javax.servlet.GenericServlet.init. Implements javax.servlet.Servlet.init. Initialize the servlet. Configuration parameters: portNumber - Port number host - Host name traceDirectory - location of trace directory startNetworkServerOnInit - start the server on initialization Parameters config:ServletConfig Doc from javax.servlet.GenericServlet.init. the `ServletConfig` object that contains configutation information for this servlet Exceptions ServletException: Doc from javax.servlet.GenericServlet.init. if an exception occurs that interrupts the servlet's normal operation

public void init(ServletConfig config) throws ServletException

Overrides javax.servlet.GenericServlet.init.

Implements javax.servlet.Servlet.init.

Initialize the servlet. Configuration parameters:

```
portNumber
```
- Port number
```
host
```
- Host name
```
traceDirectory
```
- location of trace directory
```
startNetworkServerOnInit
```
- start the server on initialization

Parameters

config:ServletConfig

Doc from javax.servlet.GenericServlet.init.

the ServletConfig object that contains configutation information for this servlet

Exceptions

ServletException:

Doc from javax.servlet.GenericServlet.init.

if an exception occurs that interrupts the servlet's normal operation

isServerStarted	back to summary
private static boolean isServerStarted(NetworkServerControl server, int ntries)

logging	back to summary
private boolean logging(LocalizedResource localUtil, boolean val, String returnMessage, PrintWriter out) Turn logging of connections on Parameters localUtil:LocalizedResource LocalizedResource to use to translate messages returnMessage:String localized continue message for continue button on error form out:PrintWriter Form PrintWriter Returns:boolean true if succeeded; false; otherwise

logging

private boolean logging(LocalizedResource localUtil, boolean val, String returnMessage, PrintWriter out)

Turn logging of connections on

Parameters

localUtil:LocalizedResource: LocalizedResource to use to translate messages
returnMessage:String: localized continue message for continue button on error form
out:PrintWriter: Form PrintWriter

Returns:boolean

true if succeeded; false; otherwise

printAsContentHeader	back to summary
private void printAsContentHeader(String str, PrintWriter out) Print the received string as a header. Parameters str:String The string to be printed as a header. out:PrintWriter Form PrintWriter

printAsContentHeader

private void printAsContentHeader(String str, PrintWriter out)

Print the received string as a header.

Parameters

str:String: The string to be printed as a header.
out:PrintWriter: Form PrintWriter

printBanner	back to summary
private void printBanner(LocalizedResource localUtil, PrintWriter out) Print Derby Network Server banner

printErrorForm	back to summary
private void printErrorForm(LocalizedResource localUtil, Exception e, String returnMessage, PrintWriter out) Display an error form Parameters localUtil:LocalizedResource LocalizedResource to use to translate messages e:Exception Exception to be displayed returnMessage:String localized continue message for continue button on error form out:PrintWriter Form PrintWriter

printErrorForm

private void printErrorForm(LocalizedResource localUtil, Exception e, String returnMessage, PrintWriter out)

Display an error form

Parameters

localUtil:LocalizedResource: LocalizedResource to use to translate messages
e:Exception: Exception to be displayed
returnMessage:String: localized continue message for continue button on error form
out:PrintWriter: Form PrintWriter

printErrorForm	back to summary
private void printErrorForm(LocalizedResource localUtil, String msg, String returnMessage, PrintWriter out) Display an error form Parameters localUtil:LocalizedResource LocalizedResource to use to translate messages msg:String String to be displayed returnMessage:String localized continue message for continue button on error form out:PrintWriter Form PrintWriter

printErrorForm

private void printErrorForm(LocalizedResource localUtil, String msg, String returnMessage, PrintWriter out)

Display an error form

Parameters

localUtil:LocalizedResource: LocalizedResource to use to translate messages
msg:String: String to be displayed
returnMessage:String: localized continue message for continue button on error form
out:PrintWriter: Form PrintWriter

runServer	back to summary
private void runServer(LocalizedResource localUtil, String returnMessage, PrintWriter out) throws ServletException Start the network server and attempt to connect to it before returning Parameters localUtil:LocalizedResource LocalizedResource to use to translate messages returnMessage:String localized continue message for continue button on error form out:PrintWriter Form PrintWriter Exceptions ServletException: throws an exception if error in starting the Network Server during initialization

runServer

private void runServer(LocalizedResource localUtil, String returnMessage, PrintWriter out) throws ServletException

Start the network server and attempt to connect to it before returning

Parameters

localUtil:LocalizedResource: LocalizedResource to use to translate messages
returnMessage:String: localized continue message for continue button on error form
out:PrintWriter: Form PrintWriter

Exceptions

ServletException:: throws an exception if error in starting the Network Server during initialization

setDefaults	back to summary
private void setDefaults() Set defaults for logging and tracing (both off)

setNetParam	back to summary
private boolean setNetParam(LocalizedResource localUtil, int max, int slice, String returnMessage, PrintWriter out) Set Network server parameters Parameters localUtil:LocalizedResource LocalizedResource to use to translate messages max:int maximum number of threads slice:int time slice for each connection returnMessage:String localized continue message for continue button on error form out:PrintWriter Form PrintWriter Returns:boolean true if succeeded; false; otherwise

setNetParam

private boolean setNetParam(LocalizedResource localUtil, int max, int slice, String returnMessage, PrintWriter out)

Set Network server parameters

Parameters

localUtil:LocalizedResource: LocalizedResource to use to translate messages
max:int: maximum number of threads
slice:int: time slice for each connection
returnMessage:String: localized continue message for continue button on error form
out:PrintWriter: Form PrintWriter

Returns:boolean

true if succeeded; false; otherwise

shutdownServer	back to summary
private boolean shutdownServer(LocalizedResource localUtil, String returnMessage, PrintWriter out) Shutdown the network server Parameters localUtil:LocalizedResource LocalizedResource to use to translate messages returnMessage:String localized continue message for continue button on error form out:PrintWriter Form PrintWriter Returns:boolean true if succeeded; false; otherwise

shutdownServer

private boolean shutdownServer(LocalizedResource localUtil, String returnMessage, PrintWriter out)

Shutdown the network server

Parameters

localUtil:LocalizedResource: LocalizedResource to use to translate messages
returnMessage:String: localized continue message for continue button on error form
out:PrintWriter: Form PrintWriter

Returns:boolean

true if succeeded; false; otherwise

traceAll	back to summary
private boolean traceAll(LocalizedResource localUtil, boolean val, String returnMessage, PrintWriter out) Change tracing for all sessions Parameters localUtil:LocalizedResource LocalizedResource to use to translate messages val:boolean if true, turn tracing on, if false turn it off returnMessage:String localized continue message for continue button on error form out:PrintWriter Form PrintWriter Returns:boolean true if succeeded; false; otherwise

traceAll

private boolean traceAll(LocalizedResource localUtil, boolean val, String returnMessage, PrintWriter out)

Change tracing for all sessions

Parameters

localUtil:LocalizedResource: LocalizedResource to use to translate messages
val:boolean: if true, turn tracing on, if false turn it off
returnMessage:String: localized continue message for continue button on error form
out:PrintWriter: Form PrintWriter

Returns:boolean

true if succeeded; false; otherwise

traceDirectory	back to summary
private boolean traceDirectory(LocalizedResource localUtil, String traceDirectory, String returnMessage, PrintWriter out) Set trace directory Parameters localUtil:LocalizedResource LocalizedResource to use to translate messages traceDirectory:String directory for trace files returnMessage:String localized continue message for continue button on error form out:PrintWriter Form PrintWriter Returns:boolean true if succeeded; false; otherwise

traceDirectory

private boolean traceDirectory(LocalizedResource localUtil, String traceDirectory, String returnMessage, PrintWriter out)

Set trace directory

Parameters

localUtil:LocalizedResource: LocalizedResource to use to translate messages
traceDirectory:String: directory for trace files
returnMessage:String: localized continue message for continue button on error form
out:PrintWriter: Form PrintWriter

Returns:boolean

true if succeeded; false; otherwise

traceSession	back to summary
private boolean traceSession(LocalizedResource localUtil, boolean val, int session, String returnMessage, PrintWriter out) Change tracing for a given session Parameters localUtil:LocalizedResource LocalizedResource to use to translate messages val:boolean if true, turn tracing on, if false turn it off session:int session to trace returnMessage:String localized continue message for continue button on error form out:PrintWriter Form PrintWriter Returns:boolean true if succeeded; false; otherwise

traceSession

private boolean traceSession(LocalizedResource localUtil, boolean val, int session, String returnMessage, PrintWriter out)

Change tracing for a given session

Parameters

localUtil:LocalizedResource: LocalizedResource to use to translate messages
val:boolean: if true, turn tracing on, if false turn it off
session:int: session to trace
returnMessage:String: localized continue message for continue button on error form
out:PrintWriter: Form PrintWriter

Returns:boolean

true if succeeded; false; otherwise

translationAvailable	back to summary
private int translationAvailable(String lang) Check if the required translation is available Parameters lang:String language we are looking for Returns:int index into language array if found, -1 otherwise;

translationAvailable