🔖 IO 示例

dunwu · dunwu · commit d860eecb2ced · 2018-04-26T16:40:58.000+08:00
diff --git a/codes/basics/src/main/java/io/github/dunwu/javase/io/FileReaderDemo.java b/codes/basics/src/main/java/io/github/dunwu/javase/io/FileReaderDemo.java
@@ -0,0 +1,48 @@
+package io.github.dunwu.javase.io;
+
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+import java.io.Reader;
+
+/**
+ * @author Zhang Peng
+ * @date 2018/4/26
+ */
+public class FileReaderDemo {
+
+    // &#23558;&#25152;&#26377;&#20869;&#23481;&#30452;&#25509;&#35835;&#21462;&#21040;&#25968;&#32452;&#20013;
+    public static int read1(Reader input, char[] c) throws IOException {
+        int len = input.read(c); // &#35835;&#21462;&#20869;&#23481;
+        return len;
+    }
+
+    // &#27599;&#27425;&#35835;&#21462;&#19968;&#20010;&#23383;&#31526;&#65292;&#30452;&#21040;&#36935;&#21040;&#23383;&#31526;&#20540;&#20026;-1&#65292;&#34920;&#31034;&#35835;&#25991;&#20214;&#32467;&#26463;
+    public static int read2(Reader input, char[] c) throws IOException {
+        int temp = 0; // &#25509;&#25910;&#27599;&#19968;&#20010;&#20869;&#23481;
+        int len = 0; // &#35835;&#21462;&#20869;&#23481;
+        while ((temp = input.read()) != -1) {
+            // &#22914;&#26524;&#19981;&#26159;-1&#23601;&#34920;&#31034;&#36824;&#26377;&#20869;&#23481;&#65292;&#21487;&#20197;&#32487;&#32493;&#35835;&#21462;
+            c[len] = (char) temp;
+            len++;
+        }
+        return len;
+    }
+
+    public static void main(String args[]) throws Exception {
+        // &#31532;1&#27493;&#12289;&#20351;&#29992;File&#31867;&#25214;&#21040;&#19968;&#20010;&#25991;&#20214;
+        File f = new File("d:" + File.separator + "test.txt");
+
+        // &#31532;2&#27493;&#12289;&#36890;&#36807;&#23376;&#31867;&#23454;&#20363;&#21270;&#29238;&#31867;&#23545;&#35937;
+        Reader input = new FileReader(f);
+
+        // &#31532;3&#27493;&#12289;&#36827;&#34892;&#35835;&#25805;&#20316;
+        char c[] = new char[1024];
+        //        int len = read1(input, c);
+        int len = read2(input, c);
+
+        // &#31532;4&#27493;&#12289;&#20851;&#38381;&#36755;&#20986;&#27969;
+        input.close();
+        System.out.println("&#20869;&#23481;&#20026;&#65306;" + new String(c, 0, len)); // &#25226;&#23383;&#31526;&#25968;&#32452;&#21464;&#20026;&#23383;&#31526;&#20018;&#36755;&#20986;
+    }
+}
diff --git a/codes/basics/src/main/java/io/github/dunwu/javase/io/FileWriterDemo.java b/codes/basics/src/main/java/io/github/dunwu/javase/io/FileWriterDemo.java
@@ -0,0 +1,28 @@
+package io.github.dunwu.javase.io;
+
+import java.io.File;
+import java.io.FileWriter;
+import java.io.Writer;
+
+/**
+ * @author Zhang Peng
+ * @date 2018/4/26
+ */
+public class FileWriterDemo {
+
+    public static void main(String args[]) throws Exception { // &#24322;&#24120;&#25243;&#20986;&#65292;&#19981;&#22788;&#29702;
+        // &#31532;1&#27493;&#12289;&#20351;&#29992;File&#31867;&#25214;&#21040;&#19968;&#20010;&#25991;&#20214;
+        File f = new File("d:" + File.separator + "test.txt"); // &#22768;&#26126;File&#23545;&#35937;
+
+        // &#31532;2&#27493;&#12289;&#36890;&#36807;&#23376;&#31867;&#23454;&#20363;&#21270;&#29238;&#31867;&#23545;&#35937;
+        Writer out = new FileWriter(f);
+        // Writer out = new FileWriter(f, true); // &#36861;&#21152;&#20869;&#23481;&#26041;&#24335;
+
+        // &#31532;3&#27493;&#12289;&#36827;&#34892;&#20889;&#25805;&#20316;
+        String str = "Hello World!!!\r\n";
+        out.write(str); // &#23558;&#20869;&#23481;&#36755;&#20986;
+
+        // &#31532;4&#27493;&#12289;&#20851;&#38381;&#36755;&#20986;&#27969;
+        out.close();
+    }
+}

-Original file line number
+Diff line change
@@ @@ -0,0 +1,28 @@ @@
 +package io.github.dunwu.javase.io;
++
 +import java.io.File;
 +import java.io.FileWriter;
 +import java.io.Writer;
++
 +/**
 + * @author Zhang Peng
 + * @date 2018/4/26
 + */
 +public class FileWriterDemo {
++
 +    public static void main(String args[]) throws Exception { // 异常抛出，不处理
 +        // 第1步、使用File类找到一个文件
 +        File f = new File("d:" + File.separator + "test.txt"); // 声明File对象
++
 +        // 第2步、通过子类实例化父类对象
 +        Writer out = new FileWriter(f);
 +        // Writer out = new FileWriter(f, true); // 追加内容方式
++
 +        // 第3步、进行写操作
 +        String str = "Hello World!!!\r\n";
 +        out.write(str); // 将内容输出
++
 +        // 第4步、关闭输出流
 +        out.close();
 +    }
 +}