java.lang.Object

de.elo.utils.webapp.status.StatusPageHandler

Direct Known Subclasses:: IXClientServletHandler

public class StatusPageHandler
extends java.lang.Object

This class is the bridge between a HttpServlet class and the classes of this package.

The function service(Request, Response, StatusDataCallback) is the main method of this class. Its purpose is to render the status page and handle predefined actions like modifying the logging level.

HttpServlet derived classes should override the HttpServlet.service function and forward requests to an instance of StatusPageHandler.

The service method of the StatusPageHandler evaluates requests with parameters: __cmd__, __loglevel__ and __mode__.

See Also:: StatusPageServletExample

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`static interface`	`StatusPageHandler.Request`	Wrapper Interface for HttpServletRequest.
`static interface`	`StatusPageHandler.Response`	Wrapper Interface for HttpServletResponse.
`static interface`	`StatusPageHandler.StatusDataCallback`	Callback interface to update the status data.

Field Summary

Fields
Modifier and Type	Field	Description
`static java.lang.String`	`URL_COMMAND_SET_LOG_LEVEL`	Append this constant to the URL, if the log level should be changed.
`static java.lang.String`	`URL_COMMAND_STATUS`	Append this constant to the URL, if the status page should be displayed in HTML.
`static java.lang.String`	`URL_COMMAND_STATUS_TEXT`	Append this constant to the URL, if the status page should be displayed in text format.
`static java.lang.String`	`URL_PARAM_COMMAND`	The parameter name for commands that are processed by the StatusPageHandler class.
`static java.lang.String`	`URL_PARAM_COMMAND_LOG_LEVEL`	The parameter value to display the status page
`static java.lang.String`	`URL_PARAM_COMMAND_STATUS`	The parameter value to display the status page
`static java.lang.String`	`URL_PARAM_LOG_LEVEL`	The parameter name to set the logging level
`static java.lang.String`	`URL_PARAM_LOGGER`	The parameter value to specify which logger is to be modified
`static java.lang.String`	`URL_PARAM_MODE`	The parameter name to specify the display mode (html or text)
`static java.lang.String`	`URL_PARAM_MODE_TEXT`	The parameter value used to display the status page in text mode rather than in HTML mode

Constructor Summary

Constructors

Constructor Description

StatusPageHandler()

Method Summary

Modifier and Type	Method	Description
`java.lang.String`	`getLogLevel()`	Returns the report level of the root logger.
`void`	`printStatus(StatusPageHandler.Response resp, boolean isAuth, boolean htmlNotText, StatusPageHandler.StatusDataCallback callback)`	This function prints the status page.
`boolean`	`service(StatusPageHandler.Request req, StatusPageHandler.Response resp, StatusPageHandler.StatusDataCallback callback)`	Called from the Servlet.service method to handle known commands.
`void`	`setLogLevel(java.lang.String logger, java.lang.String reportLevel)`	Modifies the report level of the root logger.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details
- URL_COMMAND_STATUS
  
  public static final java.lang.String URL_COMMAND_STATUS
  
  Append this constant to the URL, if the status page should be displayed in HTML. Example: "http://server:port/myapp/myservlet?" + URL_COMMAND_STATUS
  
  See Also:
  
  URL_COMMAND_STATUS_TEXT, Constant Field Values
- URL_COMMAND_STATUS_TEXT
  
  public static final java.lang.String URL_COMMAND_STATUS_TEXT
  
  Append this constant to the URL, if the status page should be displayed in text format. Example: "http://server:port/myapp/myservlet?" + URL_COMMAND_STATUS_TEXT
  
  See Also:
  
  URL_COMMAND_STATUS, Constant Field Values
- URL_COMMAND_SET_LOG_LEVEL
  
  public static final java.lang.String URL_COMMAND_SET_LOG_LEVEL
  
  Append this constant to the URL, if the log level should be changed. Example: "http://server:port/myapp/myservlet?" + URL_COMMAND_SET_LOG_LEVEL + "WARN";
  
  See Also:
  
  URL_COMMAND_STATUS, Constant Field Values
- URL_PARAM_COMMAND
  
  public static final java.lang.String URL_PARAM_COMMAND
  
  The parameter name for commands that are processed by the StatusPageHandler class.
  
  See Also:
  
  Constant Field Values
- URL_PARAM_COMMAND_STATUS
  
  public static final java.lang.String URL_PARAM_COMMAND_STATUS
  
  The parameter value to display the status page
  
  See Also:
  
  Constant Field Values
- URL_PARAM_COMMAND_LOG_LEVEL
  
  public static final java.lang.String URL_PARAM_COMMAND_LOG_LEVEL
  
  The parameter value to display the status page
  
  See Also:
  
  Constant Field Values
- URL_PARAM_MODE
  
  public static final java.lang.String URL_PARAM_MODE
  
  The parameter name to specify the display mode (html or text)
  
  See Also:
  
  Constant Field Values
- URL_PARAM_MODE_TEXT
  
  public static final java.lang.String URL_PARAM_MODE_TEXT
  
  The parameter value used to display the status page in text mode rather than in HTML mode
  
  See Also:
  
  Constant Field Values
- URL_PARAM_LOG_LEVEL
  
  public static final java.lang.String URL_PARAM_LOG_LEVEL
  
  The parameter name to set the logging level
  
  See Also:
  
  Constant Field Values
- URL_PARAM_LOGGER
  
  public static final java.lang.String URL_PARAM_LOGGER
  
  The parameter value to specify which logger is to be modified
  
  See Also:
  
  Constant Field Values
Constructor Details
- StatusPageHandler
  
  public StatusPageHandler()
Method Details
- printStatus
  
  public void printStatus(StatusPageHandler.Response resp, boolean isAuth, boolean htmlNotText, StatusPageHandler.StatusDataCallback callback) throws java.io.IOException
  
  This function prints the status page.
  
  Parameters:
  
  resp - HttpServletResponse resp
  
  isAuth - Authentication was successfully
  
  htmlNotText - true for HTML output, false for plain text output
  
  callback - StatusDataCallback object
  
  Throws:
  
  java.io.IOException
- service
  
  public boolean service(StatusPageHandler.Request req, StatusPageHandler.Response resp, StatusPageHandler.StatusDataCallback callback) throws java.io.IOException
  
  Called from the Servlet.service method to handle known commands.
  
  Parameters:
  
  req - Wrapper for HttpServletRequest
  
  resp - Wrapper fro HttpServletResponse
  
  callback - StatusDataCallback StatusData
  
  Returns:
  
  true, if the message was processed.
  
  Throws:
  
  ServletException
  
  java.io.IOException
- setLogLevel
  
  public void setLogLevel(java.lang.String logger, java.lang.String reportLevel)
  
  Modifies the report level of the root logger.
  
  Parameters:
  
  logger - Logger name, null or empty for root logger.
  
  reportLevel - one of "DEBUG", "INFO", "WARN", "ERROR"
- getLogLevel
  
  public java.lang.String getLogLevel()
  
  Returns the report level of the root logger.
  
  Returns:
  
  "DEBUG", "INFO", "WARN", "ERROR"

Class StatusPageHandler

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Details

Constructor Details

Method Details