75 lines
2.2 KiB
Dart
75 lines
2.2 KiB
Dart
/**
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组合模式（Composite Pattern）
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意图：将对象组合成树形结构以表示"部分-整体"的层次结构。组合模式使得用户对单个对象和组合对象的使用具有一致性。
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主要解决：它在我们树型结构的问题中，模糊了简单元素和复杂元素的概念，客户程序可以向处理简单元素一样来处理复杂元素，从而使得客户程序与复杂元素的内部结构解耦。
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何时使用：
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1、您想表示对象的部分-整体层次结构（树形结构）。
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2、您希望用户忽略组合对象与单个对象的不同，用户将统一地使用组合结构中的所有对象。
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如何解决：树枝和叶子实现统一接口，树枝内部组合该接口。
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*/
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main(List<String> args) {
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Employee ceo = new Employee("John", "CEO", 30000);
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Employee headSales = new Employee("Robert", "Head Sales", 20000);
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Employee headMarketing = new Employee("Michel", "Head Marketing", 20000);
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Employee clerk1 = new Employee("Laura", "Marketing", 10000);
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Employee clerk2 = new Employee("Bob", "Marketing", 10000);
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Employee salesExecutive1 = new Employee("Richard", "Sales", 10000);
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Employee salesExecutive2 = new Employee("Rob", "Sales", 10000);
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ceo.add(headSales);
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ceo.add(headMarketing);
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headSales.add(salesExecutive1);
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headSales.add(salesExecutive2);
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headMarketing.add(clerk1);
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headMarketing.add(clerk2);
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//打印该组织的所有员工
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print(ceo);
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for (Employee headEmployee in ceo.getSubordinates()) {
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print(' $headEmployee');
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for (Employee employee in headEmployee.getSubordinates()) {
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print(' $employee');
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}
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}
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}
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//////////////////////////////////////////////////////////////////
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///
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/// 创建 Employee 类，该类带有 Employee 对象的列表
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///
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class Employee {
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String name;
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String dept;
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int salary;
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List<Employee> subordinates;
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//构造函数
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Employee(this.name, this.dept, this.salary) {
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subordinates = List<Employee>();
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}
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void add(Employee e) {
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subordinates.add(e);
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}
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void remove(Employee e) {
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subordinates.remove(e);
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}
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List<Employee> getSubordinates() {
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return subordinates;
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}
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@override
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String toString() {
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return 'Employee [ name="$name", dept="$dept", salary="$salary" ]';
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}
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}
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