source: proiecte/HadoopJUnit/hadoop-0.20.1/src/webapps/hdfs/dfsnodelist.jsp @ 120

<%@ page
contentType="text/html; charset=UTF-8"
        import="javax.servlet.*"
        import="javax.servlet.http.*"
        import="java.io.*"
        import="java.util.*"
        import="org.apache.hadoop.fs.*"
        import="org.apache.hadoop.hdfs.*"
        import="org.apache.hadoop.hdfs.server.common.*"
        import="org.apache.hadoop.hdfs.server.namenode.*"
        import="org.apache.hadoop.hdfs.server.datanode.*"
        import="org.apache.hadoop.hdfs.protocol.*"
        import="org.apache.hadoop.util.*"
        import="java.text.DateFormat"
        import="java.lang.Math"
        import="java.net.URLEncoder"
%>
<%!
        JspHelper jspHelper = new JspHelper();

        int rowNum = 0;
        int colNum = 0;

        String rowTxt() { colNum = 0;
        return "<tr class=\"" + (((rowNum++)%2 == 0)? "rowNormal" : "rowAlt")
        + "\"> "; }
        String colTxt() { return "<td id=\"col" + ++colNum + "\"> "; }
        void counterReset () { colNum = 0; rowNum = 0 ; }

        long diskBytes = 1024 * 1024 * 1024;
        String diskByteStr = "GB";

        String sorterField = null;
        String sorterOrder = null;
        String whatNodes = "LIVE";

String NodeHeaderStr(String name) {
        String ret = "class=header";
        String order = "ASC";
        if ( name.equals( sorterField ) ) {
                ret += sorterOrder;
                if ( sorterOrder.equals("ASC") )
                        order = "DSC";
        }
        ret += " onClick=\"window.document.location=" +
        "'/dfsnodelist.jsp?whatNodes="+whatNodes+"&sorter/field=" + name + "&sorter/order=" +
        order + "'\" title=\"sort on this column\"";

        return ret;
}

public void generateNodeData( JspWriter out, DatanodeDescriptor d,
                String suffix, boolean alive,
                int nnHttpPort )
throws IOException {

        /* Say the datanode is dn1.hadoop.apache.org with ip 192.168.0.5
we use:
1) d.getHostName():d.getPort() to display.
Domain and port are stripped if they are common across the nodes.
i.e. "dn1"
2) d.getHost():d.Port() for "title".
i.e. "192.168.0.5:50010"
3) d.getHostName():d.getInfoPort() for url.
i.e. "http://dn1.hadoop.apache.org:50075/..."
Note that "d.getHost():d.getPort()" is what DFS clients use
to interact with datanodes.
         */
        // from nn_browsedfscontent.jsp:
        String url = "http://" + d.getHostName() + ":" + d.getInfoPort() +
        "/browseDirectory.jsp?namenodeInfoPort=" +
        nnHttpPort + "&dir=" +
        URLEncoder.encode("/", "UTF-8");

        String name = d.getHostName() + ":" + d.getPort();
        if ( !name.matches( "\\d+\\.\\d+.\\d+\\.\\d+.*" ) ) 
                name = name.replaceAll( "\\.[^.:]*", "" );    
        int idx = (suffix != null && name.endsWith( suffix )) ?
                        name.indexOf( suffix ) : -1;

                        out.print( rowTxt() + "<td class=\"name\"><a title=\""
                                        + d.getHost() + ":" + d.getPort() +
                                        "\" href=\"" + url + "\">" +
                                        (( idx > 0 ) ? name.substring(0, idx) : name) + "</a>" +
                                        (( alive ) ? "" : "\n") );
                        if ( !alive )
                                return;

                        long c = d.getCapacity();
                        long u = d.getDfsUsed();
                        long nu = d.getNonDfsUsed();
                        long r = d.getRemaining();
                        String percentUsed = StringUtils.limitDecimalTo2(d.getDfsUsedPercent());    
                        String percentRemaining = StringUtils.limitDecimalTo2(d.getRemainingPercent());    

                        String adminState = (d.isDecommissioned() ? "Decommissioned" :
                                (d.isDecommissionInProgress() ? "Decommission In Progress":
                                "In Service"));

                        long timestamp = d.getLastUpdate();
                        long currentTime = System.currentTimeMillis();
                        out.print("<td class=\"lastcontact\"> " +
                                        ((currentTime - timestamp)/1000) +
                                        "<td class=\"adminstate\">" +
                                        adminState +
                                        "<td align=\"right\" class=\"capacity\">" +
                                        StringUtils.limitDecimalTo2(c*1.0/diskBytes) +
                                        "<td align=\"right\" class=\"used\">" +
                                        StringUtils.limitDecimalTo2(u*1.0/diskBytes) +      
                                        "<td align=\"right\" class=\"nondfsused\">" +
                                        StringUtils.limitDecimalTo2(nu*1.0/diskBytes) +      
                                        "<td align=\"right\" class=\"remaining\">" +
                                        StringUtils.limitDecimalTo2(r*1.0/diskBytes) +      
                                        "<td align=\"right\" class=\"pcused\">" + percentUsed +
                                        "<td class=\"pcused\">" +
                                        ServletUtil.percentageGraph( (int)Double.parseDouble(percentUsed) , 100) +
                                        "<td align=\"right\" class=\"pcremaining`\">" + percentRemaining +
                                        "<td title=" + "\"blocks scheduled : " + d.getBlocksScheduled() + 
                                        "\" class=\"blocks\">" + d.numBlocks() + "\n");
}



public void generateDFSNodesList(JspWriter out, 
                NameNode nn,
                HttpServletRequest request)
throws IOException {
        ArrayList<DatanodeDescriptor> live = new ArrayList<DatanodeDescriptor>();    
        ArrayList<DatanodeDescriptor> dead = new ArrayList<DatanodeDescriptor>();
        jspHelper.DFSNodesStatus(live, dead);

        whatNodes = request.getParameter("whatNodes"); // show only live or only dead nodes
        sorterField = request.getParameter("sorter/field");
        sorterOrder = request.getParameter("sorter/order");
        if ( sorterField == null )
                sorterField = "name";
        if ( sorterOrder == null )
                sorterOrder = "ASC";

        jspHelper.sortNodeList(live, sorterField, sorterOrder);
        jspHelper.sortNodeList(dead, "name", "ASC");

        // Find out common suffix. Should this be before or after the sort?
        String port_suffix = null;
        if ( live.size() > 0 ) {
                String name = live.get(0).getName();
                int idx = name.indexOf(':');
                if ( idx > 0 ) {
                        port_suffix = name.substring( idx );
                }

                for ( int i=1; port_suffix != null && i < live.size(); i++ ) {
                        if ( live.get(i).getName().endsWith( port_suffix ) == false ) {
                                port_suffix = null;
                                break;
                        }
                }
        }

        counterReset();

        try {
                Thread.sleep(1000);
        } catch (InterruptedException e) {}

        if (live.isEmpty() && dead.isEmpty()) {
                out.print("There are no datanodes in the cluster");
        }
        else {

                int nnHttpPort = nn.getHttpAddress().getPort();
                out.print( "<div id=\"dfsnodetable\"> ");
                if(whatNodes.equals("LIVE")) {

                        out.print( 
                                        "<a name=\"LiveNodes\" id=\"title\">" +
                                        "Live Datanodes : " + live.size() + "</a>" +
                        "<br><br>\n<table border=1 cellspacing=0>\n" );

                        counterReset();

                        if ( live.size() > 0 ) {

                                if ( live.get(0).getCapacity() > 1024 * diskBytes ) {
                                        diskBytes *= 1024;
                                        diskByteStr = "TB";
                                }

                                out.print( "<tr class=\"headerRow\"> <th " +
                                                NodeHeaderStr("name") + "> Node <th " +
                                                NodeHeaderStr("lastcontact") + "> Last <br>Contact <th " +
                                                NodeHeaderStr("adminstate") + "> Admin State <th " +
                                                NodeHeaderStr("capacity") + "> Configured <br>Capacity (" + 
                                                diskByteStr + ") <th " + 
                                                NodeHeaderStr("used") + "> Used <br>(" + 
                                                diskByteStr + ") <th " + 
                                                NodeHeaderStr("nondfsused") + "> Non DFS <br>Used (" + 
                                                diskByteStr + ") <th " + 
                                                NodeHeaderStr("remaining") + "> Remaining <br>(" + 
                                                diskByteStr + ") <th " + 
                                                NodeHeaderStr("pcused") + "> Used <br>(%) <th " + 
                                                NodeHeaderStr("pcused") + "> Used <br>(%) <th " +
                                                NodeHeaderStr("pcremaining") + "> Remaining <br>(%) <th " +
                                                NodeHeaderStr("blocks") + "> Blocks\n" );

                                jspHelper.sortNodeList(live, sorterField, sorterOrder);
                                for ( int i=0; i < live.size(); i++ ) {
                                        generateNodeData(out, live.get(i), port_suffix, true, nnHttpPort);
                                }
                        }
                        out.print("</table>\n");
                } else {

                        out.print("<br> <a name=\"DeadNodes\" id=\"title\"> " +
                                        " Dead Datanodes : " +dead.size() + "</a><br><br>\n");

                        if ( dead.size() > 0 ) {
                                out.print( "<table border=1 cellspacing=0> <tr id=\"row1\"> " +
                                "<td> Node \n" );

                                jspHelper.sortNodeList(dead, "name", "ASC");
                                for ( int i=0; i < dead.size() ; i++ ) {
                                        generateNodeData(out, dead.get(i), port_suffix, false, nnHttpPort);
                                }

                                out.print("</table>\n");
                        }
                }
                out.print("</div>");
        }
}%>

<%
NameNode nn = (NameNode)application.getAttribute("name.node");
FSNamesystem fsn = nn.getNamesystem();
String namenodeLabel = nn.getNameNodeAddress().getHostName() + ":" + nn.getNameNodeAddress().getPort();
%>

<html>

<link rel="stylesheet" type="text/css" href="/static/hadoop.css">
<title>Hadoop NameNode <%=namenodeLabel%></title>
  
<body>
<h1>NameNode '<%=namenodeLabel%>'</h1>


<div id="dfstable"> <table>       
<tr> <td id="col1"> Started: <td> <%= fsn.getStartTime()%>
<tr> <td id="col1"> Version: <td> <%= VersionInfo.getVersion()%>, r<%= VersionInfo.getRevision()%>
<tr> <td id="col1"> Compiled: <td> <%= VersionInfo.getDate()%> by <%= VersionInfo.getUser()%>
<tr> <td id="col1"> Upgrades: <td> <%= jspHelper.getUpgradeStatusText()%>
</table></div><br>                                    

<b><a href="/nn_browsedfscontent.jsp">Browse the filesystem</a></b><br>
<b><a href="/logs/">Namenode Logs</a></b><br>
<b><a href=/dfshealth.jsp> Go back to DFS home</a></b>
<hr>
<%
        generateDFSNodesList(out, nn, request); 
%>

<%
out.println(ServletUtil.htmlFooter());
%>