Using the PageContext API, write tag handler code to access the JSP implicit variables and access web application attributes.

Using the PageContext API, write tag handler code to access the JSP implicit variables and access web application attributes.
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Using the `PageContext` API, write tag handler code to access the JSP implicit variables and access web application attributes.

A PageContext is an object that provides a context to store references to objects used by the page, encapsulates implementation-dependent features, and provides convenience methods. A JSP page implementation class can use a PageContext to run unmodified in any compliant JSP container while taking advantage of implementation-specific improvements like high performance JspWriters.

The PageContext provides a number of facilities to the page/component author and page implementor, including:

a single API to manage the various scoped namespaces
a number of convenience API's to access various public objects
a mechanism to obtain the JspWriter for output
a mechanism to manage session usage by the page
a mechanism to expose page directive attributes to the scripting environment
mechanisms to forward or include the current request to other active components in the application
a mechanism to handle errorpage exception processing

public abstract class JspContext {

	public abstract void setAttribute(String name, Object value);
	public abstract void setAttribute(String name, Object value, int scope);
	public abstract Object getAttribute(String name);
	public abstract Object getAttribute(String name, int scope);
	public abstract Object findAttribute(String name);
	public abstract void removeAttribute(String name);
	public abstract void removeAttribute(String name, int scope);
	public abstract int getAttributesScope(String name);
	public abstract Enumeration getAttributeNamesInScope(int scope);
	public abstract JspWriter getOut();

}

public abstract class PageContext extends JspContext {

	public abstract javax.servlet.http.HttpSession getSession();
	public abstract java.lang.Object getPage(); 
	public abstract javax.servlet.ServletRequest getRequest();
	public abstract javax.servlet.ServletResponse getResponse();
	public abstract java.lang.Exception getException();
	public abstract javax.servlet.ServletConfig getServletConfig();
	public abstract javax.servlet.ServletContext getServletContext();

	public abstract void forward(java.lang.String relativeUrlPath)
		throws javax.servlet.ServletException, java.io.IOException;
	public abstract void include(java.lang.String relativeUrlPath)
		throws javax.servlet.ServletException, java.io.IOException;
	public abstract void handlePageException(java.lang.Exception e)
		throws javax.servlet.ServletException, java.io.IOException;

}