FileWriter 追加文件及文件改名
我就废话不多说了,大家还是直接看代码吧~
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import java.io.File; import java.io.FileWriter; import java.io.IOException; public class FileWriterUtil { /** * 追加文件:使用FileWriter */ public static void appendMethod(String fileName, String content) { try { //打开一个写文件器,构造函数中的第二个参数true表示以追加形式写文件 FileWriter writer = new FileWriter(fileName, true ); writer.write(content); writer.close(); } catch (IOException e) { e.printStackTrace(); } } /** * 修改文件名 * @param oldFilePath * @param newFileName */ public static void reNameLogFile(String oldFilePath,String newFileName){ File f= new File(oldFilePath); String c=f.getParent(); // File mm=new File(c + File.pathSeparator + newFileName + "_" + CommonUtil.getCurrTimeForString()); File mm= new File(c + "/" + newFileName + "_" + CommonUtil.getBeforeDateStr()); if (f.renameTo(mm)){ System.out.println( "修改文件名成功!" ); } else { System.out.println( "修改文件名失败" ); } } public static void main(String[] args) { String fileName = "/Users/qin/Downloads/callLog.txt" ; String content = "new append!" ; FileWriterUtil.appendMethod(fileName, content); FileWriterUtil.appendMethod(fileName, "append end. \n" ); FileWriterUtil.reNameLogFile( "/Users/qin/Downloads/callLog.txt" , "rayda" ); } } |
Java PrintWriter&FileWriter 写入追加到文件
用PrintWriter写入文件
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import java.io.IOException; import java.io.PrintWriter; public class PrintWriteDemo { public static void main(String[] args) throws IOException { PrintWriter out = new PrintWriter( "01.txt" ); out.print( "the quick brown fox" ); out.println( " jumps over the lazy dog." ); out.write( "work is like a capricious lover whose " ); out.write( "incessant demands are resented but who is missed terribly when she is not there\n" ); out.close(); //如果不关闭文件,文件停留在buffer zone, 不会写进"01.txt"中 } } |
FileWriter只能写入文件,无法往文件中追加内容
用FileWriter写入和追加文件
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import java.io.IOException; import java.io.FileWriter; public class FileWriterDemo { public static void main(String[] args) throws IOException { FileWriter out = new FileWriter( "02.txt" ); //constructor中添加true,即FileWriter out = new FileWriter("02.txt", true)就是往02.txt中追加文件了 out.write( "work is like a capricious lover whose " ); out.write( "incessant demands are resented but who is missed terribly when she is not there\n" ); out.write( 98.7 + "\n" ); out.close(); //很重要,一定记得关闭文件 } } |
都别忘记 throws IOException
以上为个人经验,希望能给大家一个参考,也希望大家多多支持服务器之家。
原文链接:https://blog.csdn.net/u014481096/article/details/53489364