您好,登錄后才能下訂單哦!
這篇文章主要介紹了java io讀取文件操作代碼實例,文中通過示例代碼介紹的非常詳細,對大家的學習或者工作具有一定的參考學習價值,需要的朋友可以參考下
主要分為字節讀取和字符讀取,字節讀取可以一個一個讀取和字節數組讀取,字符讀取同樣之,字符讀取適合文本讀取,字節讀取皆可以
這里直接上代碼,讀取文件的9個小demo
package com.io; import org.junit.Test; import java.io.*; public class FileTest { //1、字節流字節一個一個讀取 @Test public void test() throws IOException{ InputStream fis = new FileInputStream(new File("E:\project_test\src\com\io\readme.txt")); int len; //按字節一個一個讀取 while ((len = fis.read())!=-1){ System.out.print((char)len+"t"); }; fis.close(); } //輸出結果h e l l o w o r l d //2、字節流字節數組讀取 @Test public void test1() throws IOException{ InputStream fis = new FileInputStream(new File("E:\project_test\src\com\io\readme.txt")); byte[] bytes = new byte[2]; int len ; //按字節數組讀取 bytes存儲的是讀取的數據 while ((len = fis.read(bytes))!=-1){ System.out.print((new String(bytes))+"t"); }; fis.close(); } //輸出結果 he ll ow or ld //3、緩沖字節流字節一個一個讀取 @Test public void test2() throws IOException{ BufferedInputStream bis = new BufferedInputStream(new FileInputStream(new File("E:\project_test\src\com\io\readme.txt"))); int len ; while ((len = bis.read())!=-1){ System.out.print((char)len+"t"); }; bis.close(); } //輸出結果h e l l o w o r l d //4、緩沖字節流字節數組讀取 @Test public void test3() throws IOException{ BufferedInputStream bis = new BufferedInputStream(new FileInputStream(new File("E:\project_test\src\com\io\readme.txt"))); byte[] bytes = new byte[3]; int len ; //按字節數組讀取 bytes存儲的是讀取的數據 while ((len = bis.read(bytes))!=-1){ System.out.print(new String(bytes)+"t"); }; bis.close(); } //輸出結果hel low orl drl //5、字符流一個一個讀取 @Test public void test4() throws IOException{ InputStreamReader isr = new InputStreamReader(new FileInputStream(new File("E:\project_test\src\com\io\readme.txt"))); int len ; //按字節數組讀取 bytes存儲的是讀取的數據 while ((len = isr.read())!=-1){ System.out.print((char)len+"t"); }; isr.close(); } //6、字符流字符數組讀取 @Test public void test5() throws IOException{ InputStreamReader isr = new InputStreamReader(new FileInputStream(new File("E:\project_test\src\com\io\readme.txt"))); char[] chars = new char[3]; int len ; //按字節數組讀取 bytes存儲的是讀取的數據 while ((len = isr.read(chars))!=-1){ System.out.print(new String(chars)+"t"); }; isr.close(); } //7、緩沖字符流字符一個一個讀取 @Test public void test6() throws IOException{ BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(new File("E:\project_test\src\com\io\readme.txt")))); int len ; //按字節數組讀取 bytes存儲的是讀取的數據 while ((len = br.read())!=-1){ System.out.print((char)len+"t"); }; br.close(); } //8、緩沖字符流字符數組讀取 @Test public void test7() throws IOException{ BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(new File("E:\project_test\src\com\io\readme.txt")))); char[] chars = new char[3]; int len ; //按字節數組讀取 bytes存儲的是讀取的數據 while ((len = br.read(chars))!=-1){ System.out.print(new String(chars)+"t"); }; br.close(); } //9、緩沖字符流按行讀取 @Test public void test8() throws IOException{ BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(new File("E:\project_test\src\com\io\readme.txt")))); //按字節數組讀取 bytes存儲的是讀取的數據 String str; while ( (str = br.readLine())!=null){ System.out.print(str+"t"); }; br.close(); } }
以上就是本文的全部內容,希望對大家的學習有所幫助,也希望大家多多支持億速云。
免責聲明:本站發布的內容(圖片、視頻和文字)以原創、轉載和分享為主,文章觀點不代表本網站立場,如果涉及侵權請聯系站長郵箱:is@yisu.com進行舉報,并提供相關證據,一經查實,將立刻刪除涉嫌侵權內容。