Map<String,String> map = new HashMap<String,String>();
map.containsKey("123");


String url="abc";
url.contains("123");


List<String> list = new ArrayList<String>();
list.contains("123");


import org.apache.commons.lang.StringUtils;

StringUtils.isNotBlank(id);
StringUtils.isBlank(id);

boolean flag = true;

String value ="123";
String abc= value.substring(value.indexOf(":") + 1, value.length());
String paramStr = value.substring(value.indexOf("jdc?") + 4);