javax.servlet.jsp.JspWriter#DEFAULT_BUFFER源码实例Demo

public void release() {
       out = baseOut;
try {
           // Do not flush the buffer even if we're not included (i.e.
           // we are the main page. The servlet will flush it and close
           // the stream.
           ((JspWriterImpl)out).flushBuffer();
} catch (IOException ex) {
    log.warning("Internal error flushing the buffer in release()");
}

servlet = null;
config = null;
context = null;
       elContext = null;
       elResolver = null;
       jspApplicationContext = null;
needsSession = false;
errorPageURL = null;
bufferSize = JspWriter.DEFAULT_BUFFER;
request = null;
response = null;
       depth = -1;
baseOut.recycle();
session = null;

attributes.clear();
   }
 

@Override
public void initialize(Servlet servlet, ServletRequest request,
        ServletResponse response, String errorPageURL,
        boolean needsSession, int bufferSize, boolean autoFlush)
        throws IOException {

    // initialize state
    this.servlet = servlet;
    this.config = servlet.getServletConfig();
    this.context = config.getServletContext();
    this.errorPageURL = errorPageURL;
    this.request = request;
    this.response = response;

    // initialize application context
    this.applicationContext = JspApplicationContextImpl.getInstance(context);

    // Setup session (if required)
    if (request instanceof HttpServletRequest && needsSession)
        this.session = ((HttpServletRequest) request).getSession();
    if (needsSession && session == null)
        throw new IllegalStateException(
                "Page needs a session and none is available");

    // initialize the initial out ...
    depth = -1;
    if (bufferSize == JspWriter.DEFAULT_BUFFER) {
        bufferSize = Constants.DEFAULT_BUFFER_SIZE;
    }
    if (this.baseOut == null) {
        this.baseOut = new JspWriterImpl(response, bufferSize, autoFlush);
    } else {
        this.baseOut.init(response, bufferSize, autoFlush);
    }
    this.out = baseOut;

    // register names/values as per spec
    setAttribute(OUT, this.out);
    setAttribute(REQUEST, request);
    setAttribute(RESPONSE, response);

    if (session != null)
        setAttribute(SESSION, session);

    setAttribute(PAGE, servlet);
    setAttribute(CONFIG, config);
    setAttribute(PAGECONTEXT, this);
    setAttribute(APPLICATION, context);

    isIncluded = request.getAttribute(
            RequestDispatcher.INCLUDE_SERVLET_PATH) != null;
}
 

private void _initialize(Servlet servlet, ServletRequest request,
        ServletResponse response, String errorPageURL,
        boolean needsSession, int bufferSize, boolean autoFlush) {

    // initialize state
    this.servlet = servlet;
    this.config = servlet.getServletConfig();
    this.context = config.getServletContext();
    this.errorPageURL = errorPageURL;
    this.request = request;
    this.response = response;
    
    // initialize application context
    this.applicationContext = JspApplicationContextImpl.getInstance(context);

    // Setup session (if required)
    if (request instanceof HttpServletRequest && needsSession)
        this.session = ((HttpServletRequest) request).getSession();
    if (needsSession && session == null)
        throw new IllegalStateException(
                "Page needs a session and none is available");

    // initialize the initial out ...
    depth = -1;
    if (bufferSize == JspWriter.DEFAULT_BUFFER) {
        bufferSize = Constants.DEFAULT_BUFFER_SIZE;
    }
    if (this.baseOut == null) {
        this.baseOut = new JspWriterImpl(response, bufferSize, autoFlush);
    } else {
        this.baseOut.init(response, bufferSize, autoFlush);
    }
    this.out = baseOut;

    // register names/values as per spec
    setAttribute(OUT, this.out);
    setAttribute(REQUEST, request);
    setAttribute(RESPONSE, response);

    if (session != null)
        setAttribute(SESSION, session);

    setAttribute(PAGE, servlet);
    setAttribute(CONFIG, config);
    setAttribute(PAGECONTEXT, this);
    setAttribute(APPLICATION, context);

    isIncluded = request.getAttribute(
            RequestDispatcher.INCLUDE_SERVLET_PATH) != null;
}
 

private void _initialize(Servlet servlet, ServletRequest request,
        ServletResponse response, String errorPageURL,
        boolean needsSession, int bufferSize, boolean autoFlush) {

    // initialize state
    this.servlet = servlet;
    this.config = servlet.getServletConfig();
    this.context = config.getServletContext();
    this.errorPageURL = errorPageURL;
    this.request = request;
    this.response = response;
    
    // initialize application context
    this.applicationContext = JspApplicationContextImpl.getInstance(context);

    // Setup session (if required)
    if (request instanceof HttpServletRequest && needsSession)
        this.session = ((HttpServletRequest) request).getSession();
    if (needsSession && session == null)
        throw new IllegalStateException(
                "Page needs a session and none is available");

    // initialize the initial out ...
    depth = -1;
    if (bufferSize == JspWriter.DEFAULT_BUFFER) {
        bufferSize = Constants.DEFAULT_BUFFER_SIZE;
    }
    if (this.baseOut == null) {
        this.baseOut = new JspWriterImpl(response, bufferSize, autoFlush);
    } else {
        this.baseOut.init(response, bufferSize, autoFlush);
    }
    this.out = baseOut;

    // register names/values as per spec
    setAttribute(OUT, this.out);
    setAttribute(REQUEST, request);
    setAttribute(RESPONSE, response);

    if (session != null)
        setAttribute(SESSION, session);

    setAttribute(PAGE, servlet);
    setAttribute(CONFIG, config);
    setAttribute(PAGECONTEXT, this);
    setAttribute(APPLICATION, context);

    isIncluded = request.getAttribute(
            RequestDispatcher.INCLUDE_SERVLET_PATH) != null;
}