package com.jspservletcookbook;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
/** This tag generates a thumbnail image using HTML img tag, next to text message. The user specifies the content of the message and the Heading level (i.e., <H1>-<H2>) */
public class LogoTag extends BodyTagSupport implements TryCatchFinally{
private String heading = null;
private String image =null;
//stamp.gif, 42 x 54
private String width =null;
private String height =null;
public int doStartTag() throws JspException{
//this method assumes that attribute properties have been set.
try {
int h = new Integer(heading).intValue();
if(! (h > 0 && h < 7))
throw new JspException("The 'heading' attribute value must between 1 and 6 inclusive.");
} catch (Exception e) { throw new JspException(e.getMessage()); }
return EVAL_BODY_BUFFERED;
}
public int doEndTag() throws JspException {
JspWriter out = pageContext.getOut();
String imgDir = ((HttpServletRequest) pageContext.getRequest()).getContextPath() + "/images/";
String message = getBodyContent().getString().trim();
try{
out.println(new StringBuffer("<img src=\"").append(imgDir).append(image).append("\" width=\"").append(width).append("\" height=\"").append(height).append("\" align=\"left\">").append("<H").append(heading).append(">").append(message).append("</H").append(heading).append(">").toString());
} catch (java.io.IOException io) {}
return EVAL_PAGE;
}
public void doCatch(Throwable t){
try{
pageContext.getOut().println(t.getMessage()+"<br />");
} catch (java.io.IOException io) {}
}
public void doFinally(){
//do nothing here, since we don't have any resources open
//like database connections
}
public void setHeading(String level){
this.heading= level;
}
public void setImage(String name){
this.image = name;
}
public void setWidth(String width){
this.width = width;
}
public void setHeight(String height){
this.height = height;
}
public void release(){
heading = null;
image =null;
width =null;
height =null;
}
}
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