PHP Tag Lib: PHP Custom Tag Library (TagLib)

We use tag in your HTML page such as "DIV", "H2", "P" etc in every moment in our life. Who used Grail's or Spring MVC he has knowledge on custom tag library. We can also use custom tag lib in PHP project. Below is a example of PHP custom tag lib usage:

<tglib:upper>Goes to upper</tglib:upper>

To drive output of this custom tag in PHP, you have to download and include tag lib library first from below link:

drive.google.com/PHP Tag Lib: PHP Custom Tag Library (TagLib)

We used tglib:upper in above script, so we have to make a directory in "TagLib" directory named "upper" with a function named "tglib___upper" that support $tag parameter. With will supply tag name as well as any attributes in that tag. 

Below is a sample example of "upper" tag:

function tglib___upper($tag)
{
    return strtoupper($tag['content']);
}

$tag["content"] contains body parts of the tag.

If you download and execute "tag1.php" file, below output will be generated:

Spring MVC custom body tag library example

Create two java file with following contents:

package com.pkm.maven.tag;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.BodyContent;
import javax.servlet.jsp.tagext.BodyTagSupport;

public class BodyTagOne extends BodyTagSupport {
    private int mTimes = 0;
    private BodyContent mBodyContent;
    
    public void setTimes(int pTimes) {
        mTimes = pTimes;
    }
    
    @Override
    public void setBodyContent(BodyContent pBodyContent) {
        mBodyContent = pBodyContent;
    }
    
    @Override
    public int doStartTag() throws JspException {
        if (mTimes >= 1) {
            return EVAL_BODY_TAG;
        } else {
            return SKIP_BODY;
        }
    }
    
    @Override
    public int doAfterBody() throws JspException {
        if (mTimes > 1) {
            mTimes--;
            return EVAL_BODY_TAG;
        } else {
            return SKIP_BODY;
        }
    }

    
    @Override
    public int doEndTag() throws JspException {
        try {
            if (mBodyContent != null) {
                mBodyContent.writeOut(mBodyContent.getEnclosingWriter());
            }
        } catch (Exception pIOEx) {
            throw new JspException("Error: " + pIOEx.getMessage());
        }
        return EVAL_PAGE;
    }
}





package com.pkm.maven.tag;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyContent;
import javax.servlet.jsp.tagext.BodyTagSupport;

public class BodyTagTwo extends BodyTagSupport {    
    @Override
    public int doAfterBody() throws JspException {
        try {
            BodyContent bc = getBodyContent();
            String body = bc.getString();
            JspWriter out = bc.getEnclosingWriter();
            if (body != null) {
                body = body.substring(0, 1).toUpperCase() + body.substring(1);
                out.print(body);
            }
        } 
        catch (Exception ioe) {
            throw new JspException("Error: " + ioe.getMessage());
        }
        return SKIP_BODY;
    }
}

Create the tag library descriptor (TLD) under WEB-INF folder suppose named: "UiTabLib.tld":

<taglib xmlns="http://java.sun.com/xml/ns/j2ee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
         version="2.0">
 
     <tlib-version>1.0</tlib-version>
     <short-name>Ui Tab Library</short-name>
     <uri>UiTabLib</uri>
 
     <tag>
        <name>loopText</name>
        <tag-class>com.pkm.maven.tag.BodyTagOne</tag-class>
        <body-content>JSP</body-content>
        <info>This Tag Displayes given text multiple times</info>
        <attribute>
            <name>times</name>
            <required>true</required>
            <description>Provide number of times the text will be repeated</description>
            <rtexprvalue>true</rtexprvalue>
        </attribute>
    </tag>
     <tag>
        <name>capitalize</name>
        <tag-class>com.pkm.maven.tag.BodyTagTwo</tag-class>
        <body-content>JSP</body-content>
        <info>This Tag Displays given string to be capitalized</info>
    </tag>
</taglib>

Reference & use the tag library:

<p>
    Body Tag Example: <br/>
    <% Integer counter = 1; %>
    <UiTabLib:loopText times="10">
        Counter: <%= (counter++) %><br/>
    </UiTabLib:loopText>
   <%= counter %>
</p>
<p>
    String capitalize (text to be capitalized): 
    <UiTabLib:capitalize>text to be capitalized</UiTabLib:capitalize>
</p>

Output would be like this:

Body Tag Example: 
Counter: 1
Counter: 2
Counter: 3
Counter: 4
Counter: 5
Counter: 6
Counter: 7
Counter: 8
Counter: 9
Counter: 10
11

String capitalize (text to be capitalized): Text to be capitalized

Spring MVC simple custom tag library example

Create a java file with following contents:

package com.pkm.maven.tag;

import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.SimpleTagSupport;

public class NewDateTag extends SimpleTagSupport {
    private String prefix;
 
    public void setPrefix(String prefix) {
        this.prefix = prefix;
    }
    
    @Override
    public void doTag() throws JspException, IOException {
        final JspWriter writer = getJspContext().getOut();
        String pattern = "dd/MM/yyyy H:m:s";
        SimpleDateFormat format = new SimpleDateFormat(pattern);
        if (prefix != null) {
            writer.print(prefix + " ");
        }
        writer.print(format.format(new Date()));
    }
}

Create the tag library descriptor (TLD) under WEB-INF folder suppose named: "UiTabLib.tld":

<taglib xmlns="http://java.sun.com/xml/ns/j2ee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
         version="2.0">
 
     <tlib-version>1.0</tlib-version>
     <short-name>Ui Tab Library</short-name>
     <uri>UiTabLib</uri>
  
     <tag>
         <name>newDate</name>
         <tag-class>com.pkm.maven.tag.NewDateTag</tag-class>
         <body-content>empty</body-content>
         <attribute>
             <name>prefix</name>
             <type>java.lang.String</type>
             <required>false</required>
             <rtexprvalue>true</rtexprvalue>
         </attribute>
     </tag>
</taglib>

Reference & use the tag library:

<%@taglib prefix="UiTabLib" uri="UiTabLib" %>

<p>New Date Tag Lib Output: <UiTabLib:newDate/></p>
<p>New Date Tag Lib Output: <UiTabLib:newDate prefix="Prefix"/></p>

Output would be like this:

New Date Tag Lib Output: 14/11/2014 18:25:12

New Date Tag Lib Output: Prefix 14/11/2014 18:25:12

Php Custom Tag Library

Right now I'm leaning towards the Custom Tags library. One of the best features is support for buried or nested tags like the code block below:

<?php
$current_dir = dirname(__FILE__) . DIRECTORY_SEPARATOR;
require_once $current_dir . 'customtags.php'; 
$ct = new CustomTags(array(
    'parse_on_shutdown' => true,
    'tag_directory' => $current_dir . 'tags' . DIRECTORY_SEPARATOR,
    'sniff_for_buried_tags' => true 
)); 
?> 

<ct:header example_name="Simple Example">Going Well?</ct:header>

Download php tag library from here
or go to
https://github.com/buggedcom/PHP-Custom-Tags