add questions

data/2.Java中阶/1.IO（输入输出）/2.输入输出流/Input.json

 {
     "type": "code_options",
-    "author": "陈龙",
+    "author": "clong",
     "source": "Input.md",
     "exercise_id":"",
     "notebook_enable": true

data/2.Java中阶/1.IO（输入输出）/2.输入输出流/Input.md

@@ -44,7 +44,7 @@ public class Input {
             input = br.readLine();
         } catch (IOException e) {
             e.printStackTrace();
-        }
+        } 
         System.out.println("输入数据：" + input);
     }
 }

data/2.Java中阶/1.IO（输入输出）/3.文件输入输出流/FileRead.json

 {
     "type": "code_options",
-    "author": "陈龙",
+    "author": "clong",
     "source": "FileRead.md",
     "exercise_id":"",
     "notebook_enable": true

data/2.Java中阶/1.IO（输入输出）/3.文件输入输出流/FileRead.md

@@ -65,10 +65,29 @@ public class FileRead {
         int length = 0;
         Reader reader = new InputStreamReader(new FileInputStream(filePath));
         while ((length = reader.read(chars)) != -1) {
-            for (int i = 0; i < length; i++) {
-                System.out.print(chars[i]);
-            }
+            String str = new String(chars, 0, length);
+            System.out.print(str);
         }
     }
 }
 ```
+
+### C
+
+```java
+
+import java.io.*;
+
+public class FileRead {
+    public static void main(String[] args) throws IOException {
+        String filePath = "test.txt";
+        FileReader fr2 = new FileReader(filePath);
+        char[] buf = new char[20];
+        int length;
+        while ((length = fr2.read(buf)) != -1) {
+            String str = new String(buf, 0, length);
+            System.out.print(str);
+        }
+    }
+}
+```
\ No newline at end of file

data/2.Java中阶/1.IO（输入输出）/3.文件输入输出流/FileWriter.json

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

data/2.Java中阶/1.IO（输入输出）/3.文件输入输出流/FileWriter.md

+# FileWriter
+
+
+`FileWriter` 类是从什么类直接继承而来：
+
+
+## 答案
+
+```
+OutputStreamWriter
+```
+
+## 选项
+
+### A
+
+```
+Writer
+```
+
+### B
+
+```
+FilterWriter
+```
+
+### C
+
+```java
+BufferedWriter
+```
\ No newline at end of file

data/2.Java中阶/1.IO（输入输出）/3.文件输入输出流/config.json

@@ -19,6 +19,6 @@
       }
     }
   ],
-  "export": ["FileRead.json"],
+  "export": ["FileRead.json", "FileWriter.json"],
   "title": "文件输入输出流"
 }
\ No newline at end of file

data/2.Java中阶/1.IO（输入输出）/7.ZIP压缩输入输出流/Unzip.json

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

data/2.Java中阶/1.IO（输入输出）/7.ZIP压缩输入输出流/Unzip.md

+# UnZip
+
+
+`ZipInputStream` 不包含的方法是：
+
+
+## 答案
+
+```
+createZipEntry()
+```
+
+## 选项
+
+### A
+
+```
+skip(long n)
+```
+
+### B
+
+```
+read(byte b, in off, int len)
+```
+
+### C
+
+```
+getNextEntry()
+```
+

data/2.Java中阶/1.IO（输入输出）/7.ZIP压缩输入输出流/Zip.json

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

data/2.Java中阶/1.IO（输入输出）/7.ZIP压缩输入输出流/Zip.md

+# Zip
+
+
+以下 `Zip` 程序中，能正确完成对测试文件压缩的是：
+
+
+## 答案
+
+```java
+import java.io.*;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipOutputStream;
+
+public class Zip {
+    public static void main(String[] args) throws IOException {
+        String zipFileName = "test.zip";
+        String fileName = "test.txt";
+        File file = new File(fileName);
+        ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipFileName));
+        out.putNextEntry(new ZipEntry(""));
+        FileInputStream in = new FileInputStream(file);
+        int tmp;
+        while((tmp = in.read()) != -1) {
+            out.write(tmp);
+        }
+        in.close();
+        out.close();
+    }
+}
+```
+
+## 选项
+
+### A
+
+```java
+import java.io.*;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipOutputStream;
+
+public class Zip {
+    public static void main(String[] args) throws IOException {
+        String zipFileName = "test.zip";
+        String fileName = "test.txt";
+        File file = new File(fileName);
+        ZipOutputStream out = new ZipOutputStream(zipFileName);
+        out.putNextEntry(new ZipEntry(""));
+        FileInputStream in = new FileInputStream(file);
+        int tmp;
+        while((tmp = in.read()) != -1) {
+            out.write(tmp);
+        }
+        in.close();
+        out.close();
+    }
+}
+```
+
+### B
+
+```java
+import java.io.*;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipOutputStream;
+
+public class Zip {
+    public static void main(String[] args) throws IOException {
+        String zipFileName = "test.zip";
+        String fileName = "test.txt";
+        File file = new File(fileName);
+        ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipFileName));
+        out.putNextEntry();
+        FileInputStream in = new FileInputStream(file);
+        int tmp;
+        while((tmp = in.read()) != -1) {
+            out.write(tmp);
+        }
+        in.close();
+        out.close();
+    }
+}
+```
+
+### C
+
+```java
+import java.io.*;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipOutputStream;
+
+public class Zip {
+    public static void main(String[] args) throws IOException {
+        String zipFileName = "test.zip";
+        String fileName = "test.txt";
+        File file = new File(fileName);
+        ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipFileName));
+        out.putNextEntry(new ZipEntry(""));
+        FileInputStream in = new FileOutputStream(file);
+        int tmp;
+        while((tmp = in.read()) != -1) {
+            out.write(tmp);
+        }
+        in.close();
+        out.close();
+    }
+}
+```
+

data/2.Java中阶/1.IO（输入输出）/7.ZIP压缩输入输出流/config.json

@@ -19,6 +19,6 @@
       }
     }
   ],
-  "export": [],
+  "export": ["Zip.json", "Unzip.json"],
   "title": "ZIP压缩输入输出流"
 }
\ No newline at end of file

data/2.Java中阶/2.RandomAccessFile/RandomAccessFile.json

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

data/2.Java中阶/2.RandomAccessFile/RandomAccessFile.md

+# RandomAccessFile
+
+
+以下关于 `RandomAccessFile` 的说法错误的是：
+
+
+## 答案
+
+```
+RandomAccessFile可以实现对文件以及IO节点的随机访问
+```
+
+## 选项
+
+### A
+
+```
+getFilePointer和seek是RandomAccessFile实现随机访问的核心方法
+```
+
+### B
+
+```
+RandomAccessFile使用了指针的思想
+```
+
+### C
+
+```
+RandomAccessFile可以用来实现多线程下载及断点续传
+```
+

data/2.Java中阶/2.RandomAccessFile/config.json

 {
   "node_id": "java-3c0553280d2a4b60983a5ae18e7112a4",
-  "keywords": [],
+  "keywords": ["随机", "访问", "文件"],
   "children": [],
-  "export": [],
+  "export": ["RandomAccessFile.json"],
   "title": "RandomAccessFile"
 }
\ No newline at end of file

data/2.Java中阶/3.对象序列化/1.寻找类/config.json

-{
-  "node_id": "java-21c738a097fb46a4a156d787dc4778b7",
-  "keywords": [],
-  "children": [],
-  "export": [],
-  "title": "寻找类"
-}
\ No newline at end of file

data/2.Java中阶/3.对象序列化/2.序列化的控制/config.json

-{
-  "node_id": "java-01546694ece242b6869cb662498c6670",
-  "keywords": [],
-  "children": [],
-  "export": [],
-  "title": "序列化的控制"
-}
\ No newline at end of file

data/2.Java中阶/3.对象序列化/3.使用“持久性”/config.json

-{
-  "node_id": "java-89c87044f09c446588eb96d76b766dcd",
-  "keywords": [],
-  "children": [],
-  "export": [],
-  "title": "使用“持久性”"
-}
\ No newline at end of file

data/2.Java中阶/3.对象序列化/ObjectSerializable.json

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

data/2.Java中阶/3.对象序列化/ObjectSerializable.md

+# Object Serializable
+
+
+以下关于对象的序列化与反序列化程序中，正确的是：
+
+## aop
+
+### before
+
+```java
+//
+```
+
+## 答案
+
+```java
+import java.io.*;
+import java.io.Serializable;
+
+class Student implements Serializable {
+    private String name;
+    private String sex;
+    private Integer age;
+
+    public Student(String name, String sex, Integer age) {
+        this.name = name;
+        this.sex = sex;
+        this.age = age;
+    }
+
+    @Override
+    public String toString() {
+        return "name:" + this.name + "," + "sex:" + this.sex + "," + "age:" + this.age;
+    }
+}
+
+public class SerializableDemo {
+    public static void main(String[] args) throws IOException, ClassNotFoundException {
+        // 序列化
+        Student student = new Student("小明", "男", 15);
+        System.out.println(student);
+        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("student"));
+        oos.writeObject(student);
+        oos.close();
+        // 反序列化
+        File file = new File("student");
+        ObjectInputStream ois = new ObjectInputStream(new FileInputStream(file));
+        Student student = (Student) ois.readObject();
+        ois.close();
+        System.out.println(student);
+    }
+}
+```
+
+## 选项
+
+### A
+
+```java
+import java.io.*;
+
+public class Student {
+    private String name;
+    private String sex;
+    private Integer age;
+
+    public Student(String name, String sex, Integer age) {
+        this.name = name;
+        this.sex = sex;
+        this.age = age;
+    }
+
+    @Override
+    public String toString() {
+        return "name:" + this.name + "," + "sex:" + this.sex + "," + "age:" + this.age;
+    }
+}
+
+public class SerializableDemo {
+    public static void main(String[] args) throws IOException, ClassNotFoundException {
+        // 序列化
+        Student student = new Student("小明", "男", 15);
+        System.out.println(student);
+        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("student"));
+        oos.writeObject(student);
+        oos.close();
+        // 反序列化
+        File file = new File("student");
+        ObjectInputStream ois = new ObjectInputStream(new FileInputStream(file));
+        Student student = (Student) ois.readObject();
+        ois.close();
+        System.out.println(student);
+    }
+}
+```
+
+### B
+
+```java
+import java.io.*;
+import java.io.Serializable;
+
+public class Student implements Serializable {
+    private String name;
+    private String sex;
+    private Integer age;
+
+    public Student(String name, String sex, Integer age) {
+        this.name = name;
+        this.sex = sex;
+        this.age = age;
+    }
+
+    @Override
+    public String toString() {
+        return "name:" + this.name + "," + "sex:" + this.sex + "," + "age:" + this.age;
+    }
+}
+
+public class SerializableDemo {
+    public static void main(String[] args) throws IOException, ClassNotFoundException {
+        // 序列化
+        Student student = new Student("小明", "男", 15);
+        System.out.println(student);
+        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("student"));
+        oos.writeObject(student);
+        oos.close();
+        // 反序列化
+        File file = new File("student");
+        ObjectInputStream ois = new ObjectInputStream(new FileInputStream(file));
+        Student student = ois.readObject();
+        ois.close();
+        System.out.println(student);
+    }
+}
+```
+
+### C
+
+```java
+import java.io.*;
+import java.io.Serializable;
+
+public class Student implements Serializable {
+    private String name;
+    private String sex;
+    private Integer age;
+
+    public Student(String name, String sex, Integer age) {
+        this.name = name;
+        this.sex = sex;
+        this.age = age;
+    }
+
+    @Override
+    public String toString() {
+        return "name:" + this.name + "," + "sex:" + this.sex + "," + "age:" + this.age;
+    }
+}
+
+public class SerializableDemo {
+    public static void main(String[] args) throws IOException, ClassNotFoundException {
+        // 序列化
+        Student student = new Student("小明", "男", 15);
+        System.out.println(student);
+        ObjectOutputStream oos = new ObjectOutputStream(new FileInputStream("student"));
+        oos.writeObject(student);
+        oos.close();
+        // 反序列化
+        File file = new File("student");
+        ObjectInputStream ois = new ObjectInputStream(new FileOutputStream(file));
+        Student student = (Student) ois.readObject();
+        ois.close();
+        System.out.println(student);
+    }
+}
+```
+

data/2.Java中阶/3.对象序列化/config.json

@@ -2,6 +2,6 @@
   "node_id": "java-ec1081c263a84d41b692d4821d8254e6",
   "keywords": [],
   "children": [],
-  "export": [],
+  "export": ["ObjectSerializable.json"],
   "title": "对象序列化"
 }
\ No newline at end of file

data/2.Java中阶/4.使用JDBC操作数据库/1.JDBC概述/Abstract.json

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

data/2.Java中阶/4.使用JDBC操作数据库/1.JDBC概述/Abstract.md

+# JDBC abstract
+
+
+以下关于 `JDBC` 的说法错误的是：
+
+
+## 答案
+
+```
+
+```
+
+## 选项
+
+### A
+
+```
+JDBC全称是Java DataBase Connection
+```
+
+### B
+
+```
+JDBC由一组Java语言编写的类与接口组成
+```
+
+### C
+
+```
+JDBC是一种标准Java应用编程接口
+```
+

data/2.Java中阶/4.使用JDBC操作数据库/1.JDBC概述/config.json

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

data/2.Java中阶/4.使用JDBC操作数据库/2.数据库操作/config.json

 {
   "node_id": "java-fd66a76b04b84d8da4454f6f9728aca0",
-  "keywords": [],
+  "keywords": ["数据库", "操作", "添加", "修改", "删除", "查询"],
   "children": [
     {
       "数据库基础": {