享元模式
模式定义
运用共享技术有效的支持大量粒度的对象
优点
如果系统有大量类似的对象,可以节省大量的内存及cpu资源
实现
代码语言:javascript复制import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
/**
* 需求:
* 在一张游戏地图中有无数的树,那么是不是每一颗树都是一个对象呢?
* 显然不是!不同种类的树是不同的对象,同一种类的树是一个对象
* 只是一些属性不同而已
*/
public class FlyWeightTest {
public static void main(String[] args) {
TreeNode treeNode = new TreeNode(3, 4, TreeFactory.getTree("xxx", "xxxxx"));
TreeNode treeNode1 = new TreeNode(8, 4, TreeFactory.getTree("xxx", "xxxxx"));
TreeNode treeNode3 = new TreeNode(6, 4, TreeFactory.getTree("yyy", "xxxxx"));
TreeNode treeNode4 = new TreeNode(5, 4, TreeFactory.getTree("yyy", "xxxxx"));
}
}
//树节点信息
class TreeNode{
private int x;
private int y;
private Tree tree;
public TreeNode(int x, int y, Tree tree) {
this.x = x;
this.y = y;
this.tree = tree;
}
public int getX() {
return x;
}
public void setX(int x) {
this.x = x;
}
public int getY() {
return y;
}
public void setY(int y) {
this.y = y;
}
public Tree getTree() {
return tree;
}
public void setTree(Tree tree) {
this.tree = tree;
}
}
//工厂产生树
class TreeFactory{
private static Map<String,Tree> map = new ConcurrentHashMap<>();
public static Tree getTree(String name,String data){
if (map.containsKey(name)){
return map.get(name);
}
Tree tree = new Tree(name,data);
map.put(name,tree);
return tree;
}
}
//树对象
class Tree{
private final String name;
private final String data;
public Tree(String name, String data) {
System.out.println(name "树产生");
this.name = name;
this.data = data;
}
public String getName() {
return name;
}
public String getData() {
return data;
}
}