add chain of responsibility DP

Liu Yuning · Liu Yuning · commit 71597982803a · 2017-05-21T10:10:25.000+08:00
diff --git a/src/designpattern/responsibilitychain/Client.java b/src/designpattern/responsibilitychain/Client.java
@@ -0,0 +1,26 @@
+package designpattern.responsibilitychain;
+
+/**
+ * 向链上的具体处理者对象提交请求
+ * 
+ * @author liu yuning
+ *
+ */
+public class Client {
+    public static void main(String[] args) {
+
+	Handler handlerA = new ConcreteHandlerA();
+	Handler handlerB = new ConcreteHandlerB();
+	Handler handlerC = new ConcreteHandlerC();
+
+	handlerA.setSuccessor(handlerB);
+	handlerB.setSuccessor(handlerC);
+
+	int[] requests = { 2, 14, 5, 6, 8, 23, 12, 21 };
+
+	for (int i : requests) {
+	    handlerA.handleRequest(i);
+	}
+    }
+
+}
diff --git a/src/designpattern/responsibilitychain/Handler.java b/src/designpattern/responsibilitychain/Handler.java
@@ -0,0 +1,58 @@
+package designpattern.responsibilitychain;
+
+/**
+ * 处理请求的接口
+ * 
+ * @author liu yuning
+ *
+ */
+public abstract class Handler {
+
+    protected Handler successor;
+
+    public void setSuccessor(Handler successor) {
+	this.successor = successor;
+    }
+
+    public abstract void handleRequest(int request);
+}
+
+// 具体处理者类，处理它所负责的请求，可访问它的后继者，如果可处理该请求，则处理，否则转给它的后继者处理
+class ConcreteHandlerA extends Handler {
+
+    @Override
+    public void handleRequest(int request) {
+	if (request >= 0 && request <= 10) {
+	    System.out.println(this.getClass().getName() + "处理了请求" + request);
+	} else if (successor != null) {
+	    successor.handleRequest(request);
+	}
+    }
+
+}
+
+class ConcreteHandlerB extends Handler {
+
+    @Override
+    public void handleRequest(int request) {
+	if (request > 10 && request <= 20) {
+	    System.out.println(this.getClass().getName() + "处理了请求" + request);
+	} else if (successor != null) {
+	    successor.handleRequest(request);
+	}
+    }
+
+}
+
+class ConcreteHandlerC extends Handler {
+
+    @Override
+    public void handleRequest(int request) {
+	if (request > 20 && request <= 30) {
+	    System.out.println(this.getClass().getName() + "处理了请求" + request);
+	} else if (successor != null) {
+	    successor.handleRequest(request);
+	}
+    }
+
+}
