publicclasszidian {
publicstaticvoidmain(Stringargs[]){
HashMap<String,String>hm=newHashMap<String,String>();
//add Dictionary
hm.put("username","password");
hm.put("jim","123456");
hm.put("jane","11557744");
hm.put("kevin","11165");
//测试key是否包含username,返回值为true/false
System.out.println(hm.containsKey("username"));
System.out.println("==================================");
//获取key所对应的value
System.out.println(hm.get("jim"));
//
System.out.println("==================================");
//获取整个字典数据
System.out.println(hm.entrySet());
System.out.println("==================================");
//循环打印每对key=value
Iterator<?>it=hm.entrySet().iterator();
while(it.hasNext()){
System.out.println(it.next());
}
System.out.println("==================================");
//分别获取key的值和value的值。
Iterator<String>it2=hm.keySet().iterator();
while(it2.hasNext()){
//获取字典的key(username)
Stringusername=(String)it2.next();
System.out.println(username);
//获取字典的value(节点)
Stringpassword=hm.get(username);
System.out.println(password);
}
}
}
true
==================================
123456
==================================
[kevin=11165, username=password, jim=123456, jane=11557744]
==================================
kevin=11165
username=password
jim=123456
jane=11557744
==================================
kevin
11165
username
password
jim
123456
jane
11557744
*******************************************************分割线***************************************
publicclassWindowsInfoUtil {
publicstaticHashMap<String,String> getStorage(){
//读取PC的storage信息
HashMap<String,String>map=newHashMap<String, String>();
//利用循环的方式读取各个磁盘的空间
for(charc='C';c<='F';c++){
StringdirName=c+":/";
Filewin=newFile(dirName);
if(win.exists()){
//读取到的磁盘空间是以byte为单位,为方便查看结果,转换为GB
Stringtotalspace=(String)(win.getTotalSpace()/(1024*1024*1024)+"GB");
Stringfreespace=(String)(win.getFreeSpace()/(1024*1024*1024)+"GB");
//System.out.println(freespace);
//将总空间的值和可用空间的值都存在hash map中。
map.put(c+" disk total space",totalspace);
map.put(c+" disk free space",freespace);
//System.out.println(map.keySet());
}
}
returnmap;
}
测试类:
publicclassgetStorageinfo {
@Test
publicvoidgetstorage(){
WindowsInfoUtilwin=newWindowsInfoUtil();
//HashMap<String,String> map=new HashMap<String,String>();
//HashMap的entrySet()是获取所有的键值对,keyset()是只获取Key,
Iterator<?>iter=win.getStorage().entrySet().iterator();
while(iter.hasNext()){
System.out.println(iter.next());
}
}
}
运行结果:
D disk total space=465GB
C disk free space=75GB
C disk total space=117GB
D disk free space=429GB