要求必须有如下几个方法
1put(String strKey,Object obj)放入容器
2get(String strKey)取出数据
3getSize()取得hashmap的包含元素的个数帮忙写个程序代码,谢谢
1put(String strKey,Object obj)放入容器
2get(String strKey)取出数据
3getSize()取得hashmap的包含元素的个数帮忙写个程序代码,谢谢
public class Demo<K,V> extends HashMap {
/**
*
*/
private static final long serialVersionUID = -8865167244855177229L;
public Map<String, Object> map = new HashMap<String, Object>();
public void put(String key,Object value){
map.put(key, value);
}
public Object get (String key){
return map.get(key);
}
public int getSize(){
return map.size();
}
}
public class Test {
public static void main(String args[]){
MyNewMap xmap=new MyNewMap();
xmap.put("a", 10);
xmap.put("b", new String[]{"x","y","z"});
xmap.put("c",new Date());
System.out.println(xmap.getSize());
System.out.println(xmap.get("a"));
for(String s:(String[])xmap.get("b"))
System.out.println(s);
System.out.println(xmap.get("c"));
System.out.println(xmap.get("d"));
}
} class MyNewMap{
private final static int defaultMaxSize=100;
private static int size=0;
private String[] key;
private Object[] value;
public MyNewMap(int MaxSize){
key=new String[MaxSize];
value=new Object[MaxSize];
}
public MyNewMap(){
key=new String[defaultMaxSize];
value=new Object[defaultMaxSize];
}
public void put(String strKey,Object obj){
key[size]=strKey;
value[size]=obj;
size++;
}
public Object get(String strKey){
for(int i=0;i<size;i++){
if(key[i]==strKey){
return value[i];
}
}
return null;
}
public int getSize(){
return size;
}
}3
10
x
y
z
Wed Apr 02 11:20:47 CST 2008
null
private final static int defaultMaxSize=100;
private static int size=0;//这个不能是static, 要不创建几个MAP的时候就会出错了
private String[] key;
private Object[] value;
public MyNewMap(int MaxSize){
key=new String[MaxSize];
value=new Object[MaxSize];
}
public MyNewMap(){
key=new String[defaultMaxSize];
value=new Object[defaultMaxSize];
}
public void put(String strKey,Object obj){//这个应该先找一下原来有没有同样的KEY的:有则替换旧值就可以了(size不增加),没有才这样
key[size]=strKey;
value[size]=obj;
size++;
}
public Object get(String strKey){
for(int i=0;i<size;i++){
if(key[i]==strKey){//不能用==吧
return value[i];
}
}
return null;
}
public int getSize(){
return size;
}
}