java_数组作缓存池的不可变类实例

package ming;

public class CacheImmutale {

	private static int MAX_SIZE = 10;

	private static CacheImmutale[] cache = new CacheImmutale[MAX_SIZE];

	private static int pos = 0;

	private final String name;

	private CacheImmutale(String name) {
		this.name = name;
	}

	public String getName() {
		return this.name;
	}

	public static CacheImmutale valueof(String name) {
		//遍历缓存对象
		for (int i = 0; i < MAX_SIZE; i++) {
			//如果已有相同实例，直接返回
			if (cache[i] != null && cache[i].getName().equals(name)) {
				return cache[i];
			}
		}
		//如果缓存已满
		if (pos == MAX_SIZE) {
			//把第一个缓存对象覆盖
			cache[0] = new CacheImmutale(name);
			pos = 1;
		} else {
			//把新的对象缓存起来
			cache[pos++] = new CacheImmutale(name);
		}
		return cache[pos - 1];
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj) {
			return true;
		}
		if (obj != null && obj.getClass() == CacheImmutale.class) {
			CacheImmutale ci = (CacheImmutale) obj;

			return name.equals(ci.getName());
		}
		return false;
	}

	public int hashCode(){
		return name.hashCode();
	}

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		CacheImmutale c1 = CacheImmutale.valueof("hello");
		CacheImmutale c2 = CacheImmutale.valueof("hello");
		System.out.println(c1==c2);
	}

}