Shariff is used to determine how often a page is shared in social media, but without generating requests from the displaying page to the social sites.

This document describes the Java backend. The following backends are also available:

• shariff-backend-node
• shariff-backend-perl
• shariff-backend-php

This Shariff backend is not a part of the official backends by Heise Online! It bases on the work of shariff-backend-php.

• Easy to use Java servlet
• Supports addthis, facebook, flattr, googleplus, linkedin, pinterest, reddit, stumbleupon, xing
• Parallel counter fetching to minimize response time
• Comes with a simple caching mechanism that can be replaced by other cache solutions like Ehcache
• Built with maven, package is available at Maven Central
• Uses slf4j, for log output just add a binding to your classpath
• Requires Java 8 or higher

Just add Shariff (org.shredzone.shariff:backend:1.1) to your maven or gradle dependencies, or copy the shariff.jar and json.jar to your project's lib folder. Then add the Shariff servlet to your web.xml:

<servlet>
    <servlet-name>shariff</servlet-name>
    <servlet-class>org.shredzone.shariff.ShariffServlet</servlet-class>
</servlet>
<servlet-mapping>
    <servlet-name>shariff</servlet-name>
    <url-pattern>/shariff/</url-pattern>
</servlet-mapping>

Use init-param to configure the servlet:

<servlet>
    <servlet-name>shariff</servlet-name>
    <servlet-class>org.shredzone.shariff.ShariffServlet</servlet-class>
    <init-param>
        <param-name>targets</param-name>
        <param-value>googleplus,facebook</param-value>
    </init-param>
</servlet>

The following configuration options are available:

Note that you must set up facebook.id and facebook.secret to retrieve a valid Facebook share counter. Facebook does not offer an anonymous way any more, at least none I am aware of.

If the backend runs under http://example.com/shariff/, calling the URL http://example.com/shariff/?url=http%3A%2F%2Fwww.example.com should return a JSON structure with numbers in it, e.g.:

{"facebook":1452,"googleplus":23}

You can also invoke ShariffBackend directly. Pass in the Facebook credentials via system properties facebook.id and facebook.secret if necessary. It returns the share counters for the given URLs on the command line:

java -cp shariff.jar:json.jar -Dfacebook.id=myId -Dfacebook.secret=mySecret org.shredzone.shariff.ShariffBackend http://www.heise.de

You can extend the ShariffServlet class and override its protected methods if you need more control about fetching or caching the count data.

To replace the caching mechanism (e.g. by Ehcache), override the getCountsCached() method.

For reading and normalizing the url parameter, override the getUrl() method.

For an individual test whether the given url contains a valid host or not, override the isValidHost() method.

Use this snippet to set the Facebook credentials programmatically:

Facebook facebook = getBackend().getTarget(Facebook.class);
if (facebook != null) {
    facebook.setSecret(yourClientId, yourClientSecret);
}

shariff-backend-java is released under the terms of the Apache License 2.0.