Prentice Hall and Sun Microsystems. Personal use only; do not redistribute.

346

Chapter 14 Creating Custom JSP Tag Libraries

Listing 14.24 IfConditionTag.java 

package coreservlets.tags;

import javax.servlet.jsp.*;

import javax.servlet.jsp.tagext.*;

import java.io.*;

import javax.servlet.*;

/** The condition part of an if tag.

 */

public class IfConditionTag extends BodyTagSupport {

  public int doStartTag() throws JspTagException {

    IfTag parent =

      (IfTag)findAncestorWithClass(this, IfTag.class);

    if (parent == null) {

      throw new JspTagException("condition not inside if");

    } 

    return(EVAL_BODY_TAG);

  }

  public int doAfterBody() {

    IfTag parent =

      (IfTag)findAncestorWithClass(this, IfTag.class);

    String bodyString = getBodyContent().getString();

    if (bodyString.trim().equals("true")) {

      parent.setCondition(true);

    } else {

      parent.setCondition(false);

    }

    return(SKIP_BODY);

  }

}

Second edition of this book: www.coreservlets.com; Sequel: www.moreservlets.com.

Servlet and JSP training courses by book's author: courses.coreservlets.com.