判断是否重复
一个集合中是否有重复数据

public String getCdbmj(List<Xmfp> lis)
{
Map map = new HashMap();
String mp = null;
for (int i = 0; i < lis.size(); ++i) {
Xmfp xmfp = (Xmfp)lis.get(i);
String[] cds = xmfp.getCdbmj().split(",");
for (int j = 0; j < cds.length; ++j)
if (!(map.containsKey(cds[j])))
map.put(cds[j], cds[j]);


}

Set keys = map.keySet();
for (Iterator iter = keys.iterator(); iter.hasNext(); ) {
String val = (String)iter.next();
if (mp == null) {
mp = val;
}else{
mp = mp + "," + val;
}

}

return mp;
}