标签:private override string throw indexof getchild color lint return
迭代器模式,一直没用过,也不会用。恰巧MyBatis框架中也使用到了迭代器模式,而且看起来还比较简单,在以后的工作中,若有需要咱们可模仿它的套路来干。
直接上代码
import java.util.Iterator; /** * @author Clinton Begin */ public class PropertyTokenizer implements Iterator<PropertyTokenizer> { private String name; private final String indexedName; private String index; private final String children; // 通过这个children属性建立前后两次迭代的关系 public PropertyTokenizer(String fullname) { int delim = fullname.indexOf(‘.‘); if (delim > -1) { name = fullname.substring(0, delim); children = fullname.substring(delim + 1); } else { name = fullname; children = null; } indexedName = name; delim = name.indexOf(‘[‘); if (delim > -1) { index = name.substring(delim + 1, name.length() - 1); name = name.substring(0, delim); } } public String getName() { return name; } public String getIndex() { return index; } public String getIndexedName() { return indexedName; } public String getChildren() { return children; } @Override public boolean hasNext() { return children != null; } @Override public PropertyTokenizer next() { return new PropertyTokenizer(children); } @Override public void remove() { throw new UnsupportedOperationException("Remove is not supported, as it has no meaning in the context of properties."); } }
实现 Iterator 接口就很方便的弄出一个迭代器,然后就可以使用hasNext和next方法了。
业务逻辑咱们不用管,只需要知道在调用next方法时,new了一个 PropertyTokenizer 实例, 而这个实例有个 children属性, hasNext方法就是通过判断这个children属性是否为空来作为结束迭代的判断条件。
具体的实现的我们不管,只需要领悟两点: 1. next需要干啥; 2. hasNext的如何判断?
标签:private override string throw indexof getchild color lint return
原文地址:https://www.cnblogs.com/z-qinfeng/p/12216021.html