class, interface, io

data/1.Java初阶/12.类和接口/1.类和面向对象/classic.json

+{
+  "type": "code_options",
+  "author": "刘鑫",
+  "source": "classic.md",
+  "notebook_enable": true,
+  "exercise_id": "80d2fc513df3404288cdd3d487f50893"
+}
\ No newline at end of file

data/1.Java初阶/12.类和接口/1.类和面向对象/classic.md

+# 类和类型
+
+## aop
+
+### template
+
+```java
+public class Main {
+    static class Human {
+        String label;
+        public String getLabel() {
+            return "Human";
+        }
+    }
+
+    static class Employee extends Human{
+        public String getLabel() {
+            return "$code";
+        }
+    }
+    public static void main(String[] args) throws IOException {
+        Human joe = new Employee();
+        System.out.println(joe);
+    }
+}
+```
+
+我们有两个类型：
+
+```java
+class Human {
+    String label;
+    public String getLabel() {
+        return "Human";
+    }
+}
+
+class Employee  extends Human{
+    public String getLabel() {
+        return "Employee";
+    }
+}
+```
+
+现在我们有对象
+
+```java
+Human joe = new Employe(...)
+```
+
+调用 `joe.getLable()` 的时候，返回的是？
+
+## 答案
+
+Employee
+
+## 选项
+
+### A
+
+Human
+
+### B
+
+HumanEmployee
+
+### C
+
+Main$Employee@7a81197d
+
+### D
+
+Main$Human@7a81197d
+
+

data/1.Java初阶/12.类和接口/1.类和面向对象/config.json

 {
   "keywords": [],
   "children": [],
-  "node_id": "java-461a08a44ae845018b7f0356ea928085"
+  "node_id": "java-461a08a44ae845018b7f0356ea928085",
+  "export": ["classic.json"]
 }
\ No newline at end of file

data/1.Java初阶/12.类和接口/2.抽象类/abstract.json

+{
+    "type": "code_options",
+    "author": "刘鑫",
+    "source": "abstract.md",
+    "notebook_enable": false
+}
\ No newline at end of file

data/1.Java初阶/12.类和接口/2.抽象类/abstract.md

+# 抽象类
+
+关于抽象类和接口的区别，以下说法正确的是
+
+## 答案
+
+一个实现类型只能有一个抽象基类，但是可以有多个实现接口。
+
+## 选项
+
+### 抽象类才能定义构造方法
+
+接口可以抽象构造行为
+
+### 并发安全与接口或类无关
+
+接口是线程安全的，抽象类不是
+
+### 接口和类型都可以使用 instanceof 判别
+
+可以用 instanceof 判断对象是否是某一个抽象类的实现，但是不能用来判断接口
+
+### 接口和抽象类都支持泛型
+
+抽象类可以是泛型类型，接口不能带有模板参数
\ No newline at end of file

data/1.Java初阶/12.类和接口/2.抽象类/config.json

 {
-  "keywords": [],
+  "keywords": ["面向对象", "抽象类", "接口"],
   "children": [],
   "node_id": "java-a02b334b2e364161badae34636a0284f"
 }
\ No newline at end of file

data/1.Java初阶/12.类和接口/3.接口/config.json

 {
-  "keywords": [],
+  "keywords": ["面向对象", "类型", "接口"],
   "children": [],
-  "node_id": "java-5d28bfbed25f4ae2b4d21fc1f2222e49"
+  "node_id": "java-5d28bfbed25f4ae2b4d21fc1f2222e49",
+  "export":["interface.json"]
 }
\ No newline at end of file

data/1.Java初阶/12.类和接口/3.接口/interface.json

+{
+  "type": "code_options",
+  "author": "刘鑫",
+  "source": "interface.md",
+  "notebook_enable": false,
+  "exercise_id": "462fc2e521564aa2b358cbcffb964db9"
+}
\ No newline at end of file

data/1.Java初阶/12.类和接口/3.接口/interface.md

+# 接口
+
+关于接口，错误的选项是
+
+## 答案
+
+```java
+public interface Named{
+    Named(String value);
+    String literal();
+}
+```
+
+## 选项
+
+### interface 可以有 default 实现
+
+```java
+public interface Parsec{
+    Try<String> parse(State<String> state);
+
+    default T ask(State<String> state) {
+        var result = parse(state);
+        if(result.isSuccess()){
+            return result.get();
+        } else {
+            throw result.err();
+        }
+    }
+}
+```
+
+### interface 可以有类型参数
+
+```java
+public interface Parsec<E, T>{
+    Try<T> parse(State<E> state);
+
+    default T ask(State<E> state) {
+        var result = ask(state);
+        if(result.isSuccess()){
+            return result.get();
+        } else {
+            throw result.err();
+        }
+    }
+}
+```
+
+### interface 可以实现
+
+```java
+public class One implements Parsec<String, String>{
+
+    default T parse(State<String> state) {
+        return state.next();
+    }
+}
+```
+
+### SAM
+
+```java
+public interface Parsec<E, T> {
+    public Parsec<E, T> then(Parsec<E, T> psc) {
+        return state -> {
+            this.parse(state);
+            return psc.parse(state)
+        }
+    }
+}
+```
\ No newline at end of file

data/1.Java初阶/12.类和接口/4.匿名类/anonymous.json

+{
+  "type": "code_options",
+  "author": "刘鑫",
+  "source": "anonymous.md",
+  "notebook_enable": false,
+  "exercise_id": "31ea397861004b0e9df6d767380093ef"
+}
\ No newline at end of file

data/1.Java初阶/12.类和接口/4.匿名类/anonymous.md

+# 匿名类
+
+以下代码
+
+```java
+public class App {
+    public Parsec<Character, String> text(String txt){
+        return state -> {
+            if(String.equals(state.read(txt.legth), txt)){
+                return new Success(txt);
+            } else {
+                return new NotMatch(state);
+            }
+        }
+    }
+}
+```
+
+返回的类型是：
+
+## 答案
+
+实现了 Parsec 接口的匿名类型。
+
+## 选项
+
+### A
+
+`App` 类型
+
+### B
+
+`String` 类型
+
+### C
+
+`Parsec` 接口类型
+
+### D
+
+`Function<Charactor, String>` 类型
+

data/1.Java初阶/12.类和接口/4.匿名类/config.json

 {
-  "keywords": [],
+  "keywords": ["面向对象", "匿名类", "lambda"],
   "children": [],
-  "node_id": "java-b06b5b2c7a6b44cc87744168729b31e6"
+  "node_id": "java-b06b5b2c7a6b44cc87744168729b31e6",
+  "export":[
+    "anonymous.json"
+  ]
 }
\ No newline at end of file

data/1.Java初阶/13.输入和输出/1.InputStream类型/config.json

@@ -2,6 +2,6 @@
   "node_id": "java-fc2dfe1a80f64143b4ad339378ba61da",
   "keywords": [],
   "children": [],
-  "export": [],
+  "export": ["unzip.json"],
   "title": "InputStream类型"
 }
\ No newline at end of file

data/1.Java初阶/13.输入和输出/1.InputStream类型/unzip.json

+{
+  "type": "code_options",
+  "author": "刘鑫",
+  "source": "unzip.md",
+  "notebook_enable": false,
+  "exercise_id": "cc0ec19a231d4e6e940755474c7a5b47"
+}
\ No newline at end of file

data/1.Java初阶/13.输入和输出/1.InputStream类型/unzip.md

+# 解压流
+
+已知 GZIPInputStream 是 Java 标准库中用于从 gzip 格式文件读取信息的类型，那么从一个gzip文件读取信息并解压的正确实现应该是：
+
+## 答案
+
+```java
+        String fileZip = "path_to_file.zip";
+        File destDir = new File("path_to_dest");
+        byte[] buffer = new byte[1024];
+        try (ZipInputStream zis = new ZipInputStream(new FileInputStream(fileZip))) {
+            ZipEntry zipEntry = zis.getNextEntry();
+            while (zipEntry != null) {
+                // ...
+            }
+            zis.closeEntry();
+        }
+```
+
+## 选项
+
+### 没有关闭资源
+
+```java
+        String fileZip = "path_to_file.zip";
+        File destDir = new File("path_to_dest");
+        byte[] buffer = new byte[1024];
+        ZipInputStream zis = new ZipInputStream(new FileInputStream(fileZip)) 
+        ZipEntry zipEntry = zis.getNextEntry();
+        while (zipEntry != null) {
+            // ...
+        }
+```
+
+### zip 流需要接到字节输入流上工作
+
+```java
+        String fileZip = "path_to_file.zip";
+        File destDir = new File("path_to_dest");
+        byte[] buffer = new byte[1024];
+        try (ZipInputStream zis = new ZipInputStream(fileZip)) {
+            ZipEntry zipEntry = zis.getNextEntry();
+            while (zipEntry != null) {
+                // ...
+            }
+            zis.closeEntry();
+        }
+```
+
+### 缓冲区需要分配空间
+
+```java
+        String fileZip = "path_to_file.zip";
+        File destDir = new File("path_to_dest");
+        byte[] buffer = null;
+        try (ZipInputStream zis = new ZipInputStream(new FileInputStream(fileZip))) {
+            ZipEntry zipEntry = zis.getNextEntry();
+            while (zipEntry != null) {
+                // ...
+            }
+            zis.closeEntry();
+        }
+```
\ No newline at end of file

data/1.Java初阶/13.输入和输出/2.OutputStream类型/config.json

@@ -2,6 +2,6 @@
   "node_id": "java-cc8c2e511db54a2ca2ee798f2cdbd03b",
   "keywords": [],
   "children": [],
-  "export": [],
+  "export": ["zip.json"],
   "title": "OutputStream类型"
 }
\ No newline at end of file

data/1.Java初阶/13.输入和输出/2.OutputStream类型/zip.json

+{
+  "type": "code_options",
+  "author": "刘鑫",
+  "source": "zip.md",
+  "notebook_enable": false,
+  "exercise_id": "3f6e7226750b4af5b13ee2cfbb0034fb"
+}
\ No newline at end of file

data/1.Java初阶/13.输入和输出/2.OutputStream类型/zip.md

+# 压缩流
+
+已知 ZipOutputStream 是 Java 标准库的压缩输出流，那么下列哪个选项可以正确的将指定文件压缩为zip文件？
+
+## 答案
+
+```java
+        String sourceFile = "path_to_source";
+        File fileToZip = new File(sourceFile);
+        try (FileOutputStream fos = new FileOutputStream("path_to_zip");
+             FileInputStream fis = new FileInputStream(fileToZip);
+             ZipOutputStream zipOut = new ZipOutputStream(fos);) {
+            ZipEntry zipEntry = new ZipEntry(fileToZip.getName());
+            zipOut.putNextEntry(zipEntry);
+            byte[] bytes = new byte[1024];
+            int length;
+            while ((length = fis.read(bytes)) >= 0) {
+                zipOut.write(bytes, 0, length);
+            }
+        }
+```
+
+## 选项
+
+### 没有关闭资源
+
+```java
+        String sourceFile = "path_to_source";
+        File fileToZip = new File(sourceFile);
+        FileOutputStream fos = new FileOutputStream("path_to_zip");
+        FileInputStream fis = new FileInputStream(fileToZip);
+        ZipOutputStream zipOut = new ZipOutputStream(fos);
+        ZipEntry zipEntry = new ZipEntry(fileToZip.getName());
+        zipOut.putNextEntry(zipEntry);
+        byte[] bytes = new byte[1024];
+        int length;
+        while ((length = fis.read(bytes)) >= 0) {
+            zipOut.write(bytes, 0, length);
+        }
+```
+
+
+### ZipOutputStream 不能直接读写文件，需要接入其它字节流
+
+```java
+        String sourceFile = "path_to_source";
+        File fileToZip = new File(sourceFile);
+        try (FileInputStream fis = new FileInputStream(fileToZip);
+             ZipOutputStream zipOut = new ZipOutputStream("path_to_zip");) {
+            ZipEntry zipEntry = new ZipEntry(fileToZip.getName());
+            zipOut.putNextEntry(zipEntry);
+            byte[] bytes = new byte[1024];
+            int length;
+            while ((length = fis.read(bytes)) >= 0) {
+                zipOut.write(bytes, 0, length);
+            }
+        }
+```
+
+### 缓冲区需要初始化
+
+```java
+        String sourceFile = "path_to_source";
+        File fileToZip = new File(sourceFile);
+        try (FileOutputStream fos = new FileOutputStream("path_to_zip");
+             FileInputStream fis = new FileInputStream(fileToZip);
+             ZipOutputStream zipOut = new ZipOutputStream(fos);) {
+            ZipEntry zipEntry = new ZipEntry(fileToZip.getName());
+            zipOut.putNextEntry(zipEntry);
+            byte[] bytes = null;
+            int length;
+            while ((length = fis.read(bytes)) >= 0) {
+                zipOut.write(bytes, 0, length);
+            }
+        }
+```
\ No newline at end of file

data/tree.json

@@ -1803,21 +1803,33 @@
                   {
                     "抽象类": {
                       "node_id": "java-a02b334b2e364161badae34636a0284f",
-                      "keywords": [],
+                      "keywords": [
+                        "面向对象",
+                        "抽象类",
+                        "接口"
+                      ],
                       "children": []
                     }
                   },
                   {
                     "接口": {
                       "node_id": "java-5d28bfbed25f4ae2b4d21fc1f2222e49",
-                      "keywords": [],
+                      "keywords": [
+                        "面向对象",
+                        "类型",
+                        "接口"
+                      ],
                       "children": []
                     }
                   },
                   {
                     "匿名类": {
                       "node_id": "java-b06b5b2c7a6b44cc87744168729b31e6",
-                      "keywords": [],
+                      "keywords": [
+                        "面向对象",
+                        "匿名类",
+                        "lambda"
+                      ],
                       "children": []
                     }
                   }