Points To Remember
Bootstrap is one of the major UI componnet used worldwide, So you may want to implemnt pagination using bootstrap in java , j2ee or spring application. So all you need to do is- Create a Class that will behave like a taglib.
- Create a Tld file that will map the tablib class with the jsp's.
- Use the taglib on jsp using the tld file.
Create Pagination Taglib for Jsp with Bootstrap.
Following is an example of the a custom taglib built for Bootstrap. This taglib takes in- uri -> action to be hit when clicked.
- offset -> the offset of pagination.
- count -> total number of elements to be shown.
- max -> maximum number of pages to be shown in the pagination bar.
- steps -> maximum number of elements to be shown per page.
- previous -> text to be shown for previous page link.
- next -> text to be shown for next page link.
PaginationTaglib.java
This is a java class that will behave like a taglib on jsp's.
package com.ekiras.taglib;
import java.io.Writer;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.SimpleTagSupport;
public class PaginationTaglib extends SimpleTagSupport {
private String uri;
private int offset;
private int count;
private int max = 10;
private int steps = 10;
private String previous = "Previous";
private String next = "Next";
private Writer getWriter() {
JspWriter out = getJspContext().getOut();
return out;
}
@Override
public void doTag() throws JspException {
Writer out = getWriter();
try {
out.write("<nav>");
out.write("<ul class=\"pagination\">");
if(offset<steps)
out.write(constructLink(1, previous, "disabled", true));
else
out.write(constructLink(offset-steps, previous, null, false));
for(int itr=0;itr<count;itr+=steps) {
if(offset==itr)
out.write(constructLink((itr/10+1)-1 *steps, String.valueOf(itr/10+1), "active", true));
else
out.write(constructLink(itr/10*steps, String.valueOf(itr/10+1), null , false));
}
if(offset+steps>count)
out.write(constructLink(offset+steps, next, "disabled", true));
else
out.write(constructLink(offset+steps, next, null , false));
out.write("</ul>");
out.write("</nav>");
} catch (java.io.IOException ex) {
throw new JspException("Error in Paginator tag", ex);
}
}
private String constructLink(int page, String text, String className, boolean disabled) {
StringBuilder link = new StringBuilder("<li");
if (className != null) {
link.append(" class=\"");
link.append(className);
link.append("\"");
}
if(disabled)
link.append(">").append("<a href=\"#\">"+text+"</a></li>");
else
link.append(">").append("<a href=\""+uri+"?offset="+page + "\">"+text+"</a></li>");
return link.toString();
}
public String getUri() {
return uri;
}
public void setUri(String uri) {
this.uri = uri;
}
public int getOffset() {
return offset;
}
public void setOffset(int offset) {
this.offset = offset;
}
public int getCount() {
return count;
}
public void setCount(int count) {
this.count = count;
}
public int getMax() {
return max;
}
public void setMax(int max) {
this.max = max;
}
public String getPrevious() {
return previous;
}
public void setPrevious(String previous) {
this.previous = previous;
}
public String getNext() {
return next;
}
public void setNext(String next) {
this.next = next;
}
public int getSteps() {
return steps;
}
public void setSteps(int steps) {
this.steps = steps;
}
}
customTaglib.tld
This is the .tld file that defines how to use the java class as a taglib in jsp's
<?xml version="1.0" encoding="UTF-8"?>
<taglib version="2.1" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-jsptaglibrary_2_1.xsd">
<tlib-version>1.0</tlib-version>
<short-name>paginator</short-name>
<uri>/WEB-INF/taglibs/customTaglib.tld</uri>
<tag>
<name>paginate</name>
<tag-class>com.ekiras.taglib.PaginationTaglib</tag-class>
<body-content>empty</body-content>
<attribute>
<name>next</name>
<rtexprvalue>true</rtexprvalue>
<type>java.lang.String</type>
</attribute>
<attribute>
<name>previous</name>
<rtexprvalue>true</rtexprvalue>
<type>java.lang.String</type>
</attribute>
<attribute>
<name>uri</name>
<required>true</required>
<rtexprvalue>true</rtexprvalue>
<type>java.lang.String</type>
</attribute>
<attribute>
<name>offset</name>
<required>true</required>
<rtexprvalue>true</rtexprvalue>
<type>int</type>
</attribute>
<attribute>
<name>count</name>
<required>true</required>
<rtexprvalue>true</rtexprvalue>
<type>int</type>
</attribute>
<attribute>
<name>max</name>
<rtexprvalue>true</rtexprvalue>
<type>int</type>
</attribute>
</tag>
</taglib>
<%@ taglib prefix="tag" uri="/WEB-INF/taglibs/customTaglib.tld"%>You can use this taglib in jsp by including it as mentioned above and use it like shown below.
<tag:paginate max="15" offset="${offset}" count="${count}" uri="${uri}"
next="»" previous="«" />So this when used in the application may give u an output as shown in image below.
