享元模式模式

src/main/java/top/fjy8018/designpattern/pattern/structural/flyweight/Employee.java

@@ -0,0 +1,11 @@
+package top.fjy8018.designpattern.pattern.structural.flyweight;
+
+/**
+ * 享元模式：利用共享的方式来支持大量细粒度的对象，这些对象一部分内部状态是相同的。
+ *
+ * @author F嘉阳
+ * @date 2018-10-14 16:13
+ */
+public interface Employee {
+    void report();
+}

src/main/java/top/fjy8018/designpattern/pattern/structural/flyweight/EmployeeFactory.java

@@ -0,0 +1,31 @@
+package top.fjy8018.designpattern.pattern.structural.flyweight;
+
+import lombok.extern.slf4j.Slf4j;
+
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * 员工工厂类
+ *
+ * @author F嘉阳
+ * @date 2018-10-14 16:15
+ */
+@Slf4j
+public class EmployeeFactory {
+    private static final Map<String, Employee> EMPLOYEE_MAP = new ConcurrentHashMap<>();
+
+    public static Employee getEmployee(String department) {
+        Manager manager = (Manager) EMPLOYEE_MAP.get(department);
+        // 如果在对象池中不存在，则新建对象
+        if (manager == null) {
+            manager = new Manager(department);
+            log.warn("创建{}部门经理", department);
+            String content = "报告内容……";
+            log.warn("创建报告，内容为:{}", content);
+            manager.setContent(content);
+            EMPLOYEE_MAP.put(department, manager);
+        }
+        return manager;
+    }
+}

src/main/java/top/fjy8018/designpattern/pattern/structural/flyweight/Manager.java

@@ -0,0 +1,33 @@
+package top.fjy8018.designpattern.pattern.structural.flyweight;
+
+import lombok.extern.slf4j.Slf4j;
+
+/**
+ * @author F嘉阳
+ * @date 2018-10-14 16:16
+ */
+@Slf4j
+public class Manager implements Employee {
+
+    private String content;
+
+    private String department;
+
+    /**
+     * 内部状态
+     */
+    private String title = "部门经理";
+
+    public Manager(String department) {
+        this.department = department;
+    }
+
+    public void setContent(String content) {
+        this.content = content;
+    }
+
+    @Override
+    public void report() {
+        log.info("{}{}，汇报内容：{}", department, title, content);
+    }
+}

src/test/java/top/fjy8018/designpattern/pattern/structural/flyweight/EmployeeTest.java

@@ -0,0 +1,17 @@
+package top.fjy8018.designpattern.pattern.structural.flyweight;
+
+import org.junit.jupiter.api.Test;
+
+class EmployeeTest {
+
+    private static final String departments[] = {"RD", "QA", "PM", "BD"};
+
+    @Test
+    void report() {
+        for (int i = 0; i < 10; i++) {
+            String department = departments[(int) (Math.random() * departments.length)];
+            Employee employee = EmployeeFactory.getEmployee(department);
+            employee.report();
+        }
+    }
+}