java读写文件java文件读写的文件应该放哪个路径

java如何读取一个txt文件的所有内容

import java.io.BufferedReader; import java.io.File; import java.io.FileReader; import java.io.IOException; public class ReadFile { public static void main(String[] args) throws IOException { String fileContent = readFileContent(""); System.out.println(fileContent); } //参数string为你的文件名 private static String readFileContent(String fileName) throws IOException { File file = new File(fileName); BufferedReader bf = new BufferedReader(new FileReader(file)); String content = ""; StringBuilder sb = new StringBuilder(); while(content != null){ content = bf.readLine(); if(content == null){ break; } sb.append(content.trim()); } bf.close(); return sb.toString(); } } 求采纳为满意回答。

java，编写一个程序，可以读取文件数据

package?dome.myword.test; import?java.io.BufferedInputStream; import?java.io.BufferedReader; import?java.io.FileInputStream; import?java.io.FileNotFoundException; import?java.io.FileOutputStream; import?java.io.FileReader; import?java.io.IOException; public?class?Myword?{ public?static?void?main(String[]?args)?throws?IOException?{ try?{ FileInputStream?file?=?new?FileInputStream("e:/myText.txt"); BufferedInputStream?Bfile?=?new?BufferedInputStream(file); byte[]?b?=?new?byte[1024]; String?s?=?""; int?bytesRead=0;?? while((bytesRead=Bfile.read(b))!=-1){ s+=?new?String(b,0,bytesRead); } System.out.println(s); String[]?words?=?s.split("?"); int?sum?=?words.length; int?max?=?words[0].length(); ?????? ????????String?maxWord?=?""; ????????int?avgs?=?0; ????????for?(int?i?=?1;?i?<?words.length;?i++)?{ ???????????? ????????????if(words[i].length()>max)?{??????????????? ???????????????max?=?Math.max(max,?words[i].length()); ??????????????? ???????????????maxWord?=?words[i]; ????????????} ????????????avgs?=?avgs+words[i].length()+words[0].length(); ????????} ?? ????????String?path?=?"e:/myText.txt"?; ????????FileReader?fr?=?new?FileReader(path);? ????????BufferedReader?br?=?new?BufferedReader(fr); ???????? int?x?=?0; ???????? while(br.readLine()?!=?null)?{? ???????? x++;? ???????? } ? ????????System.out.println("总行数"+x); ????????int?avg?=?avgs/sum; ????????System.out.println("平均长度："+avg); ????????System.out.println("最长单词："+maxWord); System.out.println("单词总数："+sum); Bfile.close(); ?String?fileName?=?"e:/mytextdata.txt"; ?FileOutputStream?out?=?new?FileOutputStream(fileName); ?String?str?="单词总数："+sum+" "+?"总行数:"+x+" "+"最长单词："+maxWord+" "+"平均长度："+avg; ?out.write(str.getBytes()); ?out.close(); System.out.println("输出文本完毕"); }?catch?(FileNotFoundException?e)?{ //?TODO?Auto-generated?catch?block e.printStackTrace(); } } }有问题再叫我。

下面是测试结果

java 在文件里面读写数据

亲，我也在写这题目，我按你的方法写实现了 Scanner input = new Scanner("Exercise9_19.txt");这句有问题。

将"Exercise9_19.txt"改为你前面定义的File变量sourceFile才能正确读出。

正确写法：Scanner input = new Scanner(sourceFile); 不然你报的异常为java.util.InputMismatchException期望参数不匹配异常。

java文件读写的文件应该放哪个路径

放文件所在路径啊,比如我的文件在C盘的aa文件夹下的bb.txt File f=new File("C://aa/bb.txt"); InputStreamReader isr=new InputStreamReader(f); BufferedReader buf=new BufferedReader(isr); String s=buf.readLine(); OK！！！