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(xì),對大家的學(xué)習(xí)或者工作具有一定的參考學(xué)習(xí)價值,需要的朋友可以參考下
成都創(chuàng)新互聯(lián)公司是一家專注于成都網(wǎng)站制作、成都網(wǎng)站建設(shè)、外貿(mào)營銷網(wǎng)站建設(shè)與策劃設(shè)計,沛縣網(wǎng)站建設(shè)哪家好?成都創(chuàng)新互聯(lián)公司做網(wǎng)站,專注于網(wǎng)站建設(shè)10年,網(wǎng)設(shè)計領(lǐng)域的專業(yè)建站公司;建站業(yè)務(wù)涵蓋:沛縣等地區(qū)。沛縣做網(wǎng)站價格咨詢:13518219792
主要分為字節(jié)讀取和字符讀取,字節(jié)讀取可以一個一個讀取和字節(jié)數(shù)組讀取,字符讀取同樣之,字符讀取適合文本讀取,字節(jié)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(jié)流字節(jié)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(jié)一個一個讀取 while ((len = fis.read())!=-1){ System.out.print((char)len+"t"); }; fis.close(); } //輸出結(jié)果h e l l o w o r l d //2、字節(jié)流字節(jié)數(shù)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(jié)數(shù)組讀取 bytes存儲的是讀取的數(shù)據(jù) while ((len = fis.read(bytes))!=-1){ System.out.print((new String(bytes))+"t"); }; fis.close(); } //輸出結(jié)果 he ll ow or ld //3、緩沖字節(jié)流字節(jié)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(jié)果h e l l o w o r l d //4、緩沖字節(jié)流字節(jié)數(shù)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(jié)數(shù)組讀取 bytes存儲的是讀取的數(shù)據(jù) while ((len = bis.read(bytes))!=-1){ System.out.print(new String(bytes)+"t"); }; bis.close(); } //輸出結(jié)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(jié)數(shù)組讀取 bytes存儲的是讀取的數(shù)據(jù) while ((len = isr.read())!=-1){ System.out.print((char)len+"t"); }; isr.close(); } //6、字符流字符數(shù)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(jié)數(shù)組讀取 bytes存儲的是讀取的數(shù)據(jù) 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(jié)數(shù)組讀取 bytes存儲的是讀取的數(shù)據(jù) while ((len = br.read())!=-1){ System.out.print((char)len+"t"); }; br.close(); } //8、緩沖字符流字符數(shù)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(jié)數(shù)組讀取 bytes存儲的是讀取的數(shù)據(jù) 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(jié)數(shù)組讀取 bytes存儲的是讀取的數(shù)據(jù) String str; while ( (str = br.readLine())!=null){ System.out.print(str+"t"); }; br.close(); } }
以上就是本文的全部內(nèi)容,希望對大家的學(xué)習(xí)有所幫助,也希望大家多多支持創(chuàng)新互聯(lián)。