js向action中传参中文乱码

contentUrl = "maintenancemanage!showCertainContent.action?time=" + time + "&menuQuerySelect=" + currentSelectMenu.id

       + "&areaId=" + unitId + "&certainType=area&areaName=" + encodeURI(unitName);

public void setAreaName(String areaName) {
String tmp = null;
try {
tmp = new String(areaName.getBytes("iso-8859-1"),"utf-8");
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
this.areaName = tmp;
}