day20

abc.txt

@@ -0,0 +1 @@
+xiaoniankuailehappynewyearxiaoniankuailehappynewyearxiaoniankuailehappynewyear

fw.txt

@@ -0,0 +1 @@
+爱扣钉꿈

src/main/java/com/sf/day20/Test01.java

@@ -0,0 +1,54 @@
+package com.sf.day20;
+
+import org.junit.Test;
+
+import java.io.*;
+
+public class Test01 {
+    //fileWriter
+    @Test
+    public void t1() throws IOException {
+        FileWriter fileWriter = new FileWriter(new File("D:\\c.txt"));
+        fileWriter.write(97);
+        fileWriter.write('b');
+        fileWriter.write('c');
+        fileWriter.write(30000);
+        fileWriter.close();
+    }
+
+    @Test
+    public void t2() throws IOException {
+        FileWriter fileWriter = new FileWriter(new File("abc.txt"),true);
+        String str = "xiaoniankuailehappynewyear";
+        char[] chars = str.toCharArray();
+        //写出
+        fileWriter.write(chars);
+        fileWriter.close();
+    }
+
+    @Test
+    public void t3() throws IOException {
+        FileReader fileReader = new FileReader(new File("D:\\a.txt"));
+        FileWriter fileWriter = new FileWriter(new File("D:\\d.txt"),true);
+        char[] chars = new char[5];
+        int data;
+        while ((data = fileReader.read(chars)) != -1){
+            fileWriter.write(chars);
+        }
+        fileReader.close();
+        fileWriter.close();
+    }
+
+    @Test
+    public void t4() throws IOException {
+        FileWriter fileWriter = new FileWriter(new File("fw.txt"));
+        fileWriter.write('爱');
+        fileWriter.write('扣');
+        fileWriter.write('钉');
+        fileWriter.write(45000);
+        fileWriter.flush();
+        fileWriter.close();
+    }
+
+
+}