SightlyParamExample.java

#Initialize a variable
<sly data-sly-test.pagePath="${currentPage.path}"/>
<sly data-sly-test.someString='test'/>
<sly data-sly-use.SomeOtherObject="${'TopNavHelperUse' @ test='test'}">

<sly class="sightly-topnav" data-sly-use.topnav="${'Topnav' @ pageNumber='5', someString=someString, pageObject=currentPage, helperString=SomeOtherObject.test}"/>

${topnav.totalPage} ${topnav.someOtherString} ${topnav.pagePath} ${topnav.helperTest}

#Here is Output

15 test and test2 /sometestPath testtest5

#Here is Java Class Example
import com.adobe.cq.sightly.WCMUse;

import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import com.day.cq.commons.Filter;
import com.day.cq.wcm.api.Page;
import com.day.cq.wcm.api.PageFilter;

public class Topnav extends WCMUse {
  public int getTotalPage(){
    return Integer.parseInt(get("pageNumber",String.class))+10;
  }
  
  public String getSomeOtherString(){
    return get("someString",String.class)+" and test2";
  }
  
  public String getPagePath(){
    return get("pageObject",Page.class).getPath();
  }
  
  public String getHelperTest(){
    return get("helperString",String.class) + "test5";
  }
}

#Other Class
public class TopNavHelperUse extends WCMUse {
  public String getTest(){
   return get("test",String.class); 
  }
}