SP.ListDataSource Class

<asp:Content ID="Main" ContentPlaceHolderID="PlaceHolderMain" runat="server">
<script type="text/ecmascript" language="ecmascript">

function runCode() {
    var clientContext = new SP.ClientContext(); 
    site = clientContext.get_web();
    clientContext.load(site);

    listCollection = site.get_lists();
    clientContext.load(listCollection, 'Include(Title,DataSource)');
    clientContext.executeQueryAsync(Function.createDelegate(this, this.onQuerySucceeded), Function.createDelegate(this, this.onQueryFailed));
}

function onQuerySucceeded() {
    var ds;
    var targetList;
    var messageExternal = "External Lists:";
    var messageNormal = "Normal Lists:";
    var listEnumerator = listCollection.getEnumerator();
    while (listEnumerator.moveNext()) {
        targetList = listEnumerator.get_current();
        // Get a ListDataSource object.
        ds = targetList.get_dataSource();
        if (!SP.ScriptUtility.isNullOrUndefined(ds)) {
            messageExternal += '\n\t' + targetList.get_title();
            // Get connection properties of the ListDataSource object.
            messageExternal += '(Entity=' + ds.get_properties()["Entity"] + ';  ';
            messageExternal += 'LOB System=' + ds.get_properties()["LobSystemInstance"] + ');  ';
        }
        else {
            messageNormal += "\n\t" + targetList.get_title();
        }
    }
    alert(messageExternal + "\n\n" + messageNormal);
}

function onQueryFailed(sender, args) {
    alert('Request failed. \nError: ' + args.get_message() + '\nStackTrace: ' + args.get_stackTrace());
}

</script>

    <input id="Button1" type="button" value="Run Code" onclick="runCode()" />

</asp:Content>