add type questions

data/2.Java中阶/6.网络编程/8.使用代理服务器/Proxy.json

+{
+    "type": "code_options",
+    "author": "clong",
+    "source": "Proxy.md",
+    "exercise_id": "",
+    "notebook_enable": true
+}
\ No newline at end of file

data/2.Java中阶/6.网络编程/8.使用代理服务器/Proxy.md

+# Proxy
+
+
+下列对http请求使用代理的方式正确的是：
+
+
+## 答案
+
+```
+以上选择均正确
+```
+
+## 选项
+
+### A
+
+```java
+// 在你发起Http请求之前设置代理属性
+Properties prop = System.getProperties();
+prop.setProperty("http.proxyHost",  proxyHost);
+prop.setProperty("http.proxyPort",  proxyPort);
+```
+
+### B
+
+```java
+// 通过Proxy来配置代理信息
+URL url = new URL("http://www.baidu.com");
+Proxy proxy = new Proxy(Proxy.Type.HTTP, new InetSocketAddress(proxyHost, proxyPort)); 
+URLConnection conn = url.openConnection(proxy);
+```
+
+### C
+
+```java
+// httpclient设置代理
+HttpClient client = HttpClient.newBuilder()
+                .version(HttpClient.Version.HTTP_2)
+                .connectTimeout(Duration.ofSeconds(10))
+                .proxy(ProxySelector.of(new InetSocketAddress(proxyHost, proxyHost)))
+                .build();
+```

data/2.Java中阶/6.网络编程/8.使用代理服务器/config.json

@@ -19,6 +19,6 @@
       }
     }
   ],
-  "export": [],
+  "export": ["Proxy.json"],
   "title": "使用代理服务器"
 }
\ No newline at end of file

data/2.Java中阶/7.类型信息/1.Class对象/Class.json

+{
+    "type": "code_options",
+    "author": "clong",
+    "source": "Class.md",
+    "exercise_id": "",
+    "notebook_enable": true
+}
\ No newline at end of file

data/2.Java中阶/7.类型信息/1.Class对象/Class.md

+# Class
+
+
+以下关于Class对象的说法错误的是：
+
+
+## 答案
+
+```
+使用字面常量获取类对象会触发类的初始化
+```
+
+## 选项
+
+### A
+
+```java
+可以通过Class.forName或者getClass获取类的Class对象
+Class clazz = Class.forName("com.csdn.Test");
+// 或者
+Test test = new Test();
+Class clazz = test.getClass();
+```
+
+### B
+
+```java
+可以通过字面常量的方式获取Class对象
+Class clazz = Test.class;
+```
+
+### C
+
+```
+使用getClass和forName获取类对象都将会触发类的初始化
+```

data/2.Java中阶/7.类型信息/1.Class对象/config.json

@@ -27,6 +27,6 @@
       }
     }
   ],
-  "export": [],
+  "export": ["Class.json"],
   "title": "Class对象"
 }
\ No newline at end of file

data/2.Java中阶/7.类型信息/2.类型转换前先做检查/Instanceof.json

+{
+    "type": "code_options",
+    "author": "clong",
+    "source": "Instanceof.md",
+    "exercise_id": "",
+    "notebook_enable": true
+}
\ No newline at end of file

data/2.Java中阶/7.类型信息/2.类型转换前先做检查/Instanceof.md

+# Instanceof
+
+
+以下关于 `instanceof` 的说法错误的是：
+
+
+## 答案
+
+```
+instanceof是类方法
+```
+
+## 选项
+
+### A
+
+```
+instanceof用来判断一个对象是否是另一个类的实例
+```
+
+### B
+
+```
+判断的对象不能是基本类型
+```
+
+### C
+
+```java
+// instanceof伪代码描述为
+boolean result;
+if (obj == null) {
+  result = false;
+} else {
+  try {
+      T temp = (T) obj;
+      result = true;
+  } catch (ClassCastException e) {
+      result = false;
+  }
+}
+```

data/2.Java中阶/7.类型信息/2.类型转换前先做检查/config.json

 {
   "node_id": "java-48593d705752415e95c42b09d36bc2a4",
-  "keywords": [],
+  "keywords": ["instanceof"],
   "children": [
     {
       "使用类字面常量": {
@@ -27,6 +27,6 @@
       }
     }
   ],
-  "export": [],
+  "export": ["Instanceof.json"],
   "title": "类型转换前先做检查"
 }
\ No newline at end of file

data/2.Java中阶/7.类型信息/4.instanceof与Class的等价性/Instanceof.json

+{
+    "type": "code_options",
+    "author": "clong",
+    "source": "Instanceof.md",
+    "exercise_id": "",
+    "notebook_enable": true
+}
\ No newline at end of file

data/2.Java中阶/7.类型信息/4.instanceof与Class的等价性/Instanceof.md

+# Instanceof
+
+
+已知Person是Man的父类，以下结果为True的是：
+
+## aop
+
+### before
+
+```java
+Man man = new Man();
+Person person = new Person();
+```
+
+## 答案
+
+```
+man instanceof Person
+```
+
+## 选项
+
+### A
+
+```java
+man.getClass.equals(Person.class)
+```
+
+### B
+
+```java
+Man.class.isInstance(person)
+```
+
+### C
+
+```java
+person.getClass() == Man.class
+```

data/2.Java中阶/7.类型信息/4.instanceof与Class的等价性/config.json

@@ -2,6 +2,6 @@
   "node_id": "java-feca89c3fb9e4bcaba3f1f95e8ad4753",
   "keywords": [],
   "children": [],
-  "export": [],
+  "export": ["Instanceof.json"],
   "title": "instanceof与Class的等价性"
 }
\ No newline at end of file

data/2.Java中阶/7.类型信息/5.反射：运行时类信息/Reflect.json

+{
+    "type": "code_options",
+    "author": "clong",
+    "source": "Reflect.md",
+    "exercise_id": "",
+    "notebook_enable": true
+}
\ No newline at end of file

data/2.Java中阶/7.类型信息/5.反射：运行时类信息/Reflect.md

+# Reflect
+
+
+下列关于JAVA反射的说法正确的是：
+
+## aop
+
+### before
+
+```java
+
+```
+
+## 答案
+
+```
+以上说法均正确
+```
+
+## 选项
+
+### A
+
+```
+反射机制作用在程序运行状态
+```
+
+### B
+
+```
+能动态获取类的属性及方法并能进行调用
+```
+
+### C
+
+```
+反射首先要获取类的Class类对象
+```

data/2.Java中阶/7.类型信息/5.反射：运行时类信息/ReflectTest.json

+{
+    "type": "code_options",
+    "author": "clong",
+    "source": "ReflectTest.md",
+    "exercise_id": "",
+    "notebook_enable": true
+}
\ No newline at end of file

data/2.Java中阶/7.类型信息/5.反射：运行时类信息/ReflectTest.md

+# ReflectTest
+
+
+以下程序是关于反射的一个例子，程序的控制台打印为：
+```java
+public class Reflect {
+    public static void main(String[] args) throws NoSuchMethodException, InvocationTargetException, InstantiationException, IllegalAccessException {
+        Class clazz = Student.class;
+        Constructor con = clazz.getConstructor(String.class, Integer.class);
+        Student student1 = (Student) con.newInstance("小铭", 24);
+        Student student2 = new Student("小铭", 24);
+        System.out.println(student2 == student1);
+        System.out.println(student2.equals(student1));
+    }
+}
+```
+
+## aop
+
+### before
+
+```java
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+
+class Student {
+    private String name;
+    private Integer age;
+
+    public Student() {}
+
+    public Student(String name, Integer age) {
+        this.name = name;
+        this.age = age;
+    }
+
+    @Override
+    public String toString() {
+        return "Student{" +
+                "name='" + name + '\'' +
+                ", age=" + age +
+                '}';
+    }
+}
+```
+
+## 答案
+
+```
+false
+false
+```
+
+## 选项
+
+### A
+
+```
+false
+true
+```
+
+### B
+
+```
+true
+false
+```
+
+### C
+
+```
+true
+true
+```

data/2.Java中阶/7.类型信息/5.反射：运行时类信息/config.json

 {
   "node_id": "java-42b26ca8a2384dcfb02fca6e159ace67",
-  "keywords": [],
+  "keywords": ["annotation"],
   "children": [
     {
       "类方法抽取器": {
@@ -127,6 +127,6 @@
       }
     }
   ],
-  "export": [],
+  "export": ["Reflect.json", "ReflectTest.json"],
   "title": "反射：运行时类信息"
 }
\ No newline at end of file

data/2.Java中阶/7.类型信息/6.动态代理/DynamicProxy.json

+{
+    "type": "code_options",
+    "author": "clong",
+    "source": "DynamicProxy.md",
+    "exercise_id": "",
+    "notebook_enable": true
+}
\ No newline at end of file

data/2.Java中阶/7.类型信息/6.动态代理/DynamicProxy.md

+# DynamicProxy
+
+
+下列关于JAVA动态代理的说法正确的是：
+
+
+
+## 答案
+
+```
+以上说法均正确
+```
+
+## 选项
+
+### A
+
+```
+为对象提供一个代理，控制对对象的访问
+```
+
+### B
+
+```
+动态代理有两种实现方式：JDK动态代理实现和CGlib字节码技术实现
+```
+
+### C
+
+```
+JDK动态代理只能代理接口而不能代理类
+```

data/2.Java中阶/7.类型信息/6.动态代理/DynamicProxyTest.json

+{
+    "type": "code_options",
+    "author": "clong",
+    "source": "DynamicProxyTest.md",
+    "exercise_id": "",
+    "notebook_enable": true
+}
\ No newline at end of file

data/2.Java中阶/7.类型信息/6.动态代理/DynamicProxyTest.md

+# DynamicProxyTest
+
+
+以下程序是关于动态代理的一个例子，1和2处填入正确的是：
+```java
+
+interface Person {
+    void speak(String text);
+}
+
+public class DynamicProxyTest {
+    public static void main(String[] args) {
+        InvocationHandler handler = new InvocationHandler() {
+            @Override
+            public Object invoke(Object proxy, Method method, Object[] args) {
+                if (method.getName().equals("speak")) {
+                    System.out.println("准备");
+                    System.out.println(args[0]);
+                    System.out.println("结束");
+                }
+                return null;
+            }
+        };
+        Person person = (Person) Proxy.newProxyInstance(
+                1,
+                2,
+                handler);
+        person.speak("你好，很高兴认识你。");
+    }
+}
+```
+
+
+## 答案
+
+```
+Person.class.getClassLoader()
+new Class[] { Person.class }
+```
+
+## 选项
+
+### A
+
+```
+Person.getClassLoader()
+Person.class
+```
+
+### B
+
+```
+Person.class.getClassLoader()
+Person.getClass()
+```
+
+### C
+
+```
+Person.getClassLoader()
+new Class[] { Person.class }
+```

data/2.Java中阶/7.类型信息/6.动态代理/config.json

@@ -2,6 +2,6 @@
   "node_id": "java-f7be740717c442c4a489a8c8d675f38c",
   "keywords": [],
   "children": [],
-  "export": [],
+  "export": ["DynamicProxy.json", "DynamicProxyTest.json"],
   "title": "动态代理"
 }
\ No newline at end of file

data/2.Java中阶/7.类型信息/7.空对象/None.json

+{
+    "type": "code_options",
+    "author": "clong",
+    "source": "None.md",
+    "exercise_id": "",
+    "notebook_enable": true
+}
\ No newline at end of file

data/2.Java中阶/7.类型信息/7.空对象/None.md

+# 空对象
+
+
+下列关于空对象的说法错误的是：
+
+
+
+## 答案
+
+```
+构造空对象是java内置的
+```
+
+## 选项
+
+### A
+
+```
+空对象，没有赋值过，但是却在内存中存在
+```
+
+### B
+
+```
+空对象能避免报空指针异常
+```
+
+### C
+
+```
+有时候还是要判断对象是否为空对象
+```

data/2.Java中阶/7.类型信息/7.空对象/config.json

@@ -11,6 +11,6 @@
       }
     }
   ],
-  "export": [],
+  "export": ["None.json"],
   "title": "空对象"
 }
\ No newline at end of file