if (login.username == null || login.username.length == 0) throw "Can't add a login with a null or empty username."; 
 if (login.username == null) throw "Can't add a login with a null username."; 
    addLogin : function (login) {        // Sanity check the login        if (login.hostname == null || login.hostname.length == 0)            throw "Can't add a login with a null or empty hostname.";        if (login.username == null || login.username.length == 0)            throw "Can't add a login with a null or empty username.";        if (login.password == null || login.password.length == 0)            throw "Can't add a login with a null or empty password.";        if (!login.httpRealm && !login.formSubmitURL)            throw "Can't add a login without a httpRealm or formSubmitURL.";        // Look for an existing entry.        var logins = this.findLogins({}, login.hostname, login.formSubmitURL,                                     login.httpRealm);        if (logins.some(function(l) { return login.username == l.username }))            throw "This login already exists.";        this.log("Adding login: " + login);        return this._storage.addLogin(login);    },
5459	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/5459/6ccd2aa9c9d8760e31362abc1f3a246dd9a8724f/nsLoginManager.js/buggy/toolkit/components/passwordmgr/src/nsLoginManager.js