请问java如何打开一个txt文件,写入一行内容,再关闭。谢谢 请问java如何打开一个txt文件,写入一行内容,再关闭。谢谢 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 import java.io.FileNotFoundException;import java.io.FileOutputStream;public class Test { public static void main(String args[]){ try { FileOutputStream f=new FileOutputStream("C:/test.txt",true); f.write("\r\n你好,this is a demo".getBytes()); f.close(); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } }} void write2file(String out){ FileWriter fw = new FileWriter("c:\e.txt"); BufferedWriter bw = new BufferedWriter(fw); bw.writer(out); bw.flush(); bw.close(); return;} public void readFile() throws Throwable{ FIle file=new File(path); FileInputStream r=new FileInputStream(file); InputStreamReader bridgeStream=new InputStreamReader(r); BufferedReader bufReader=new BufferedReader(bridgeStream); String str; while((str=bufReader.readLine())!=null){ this.linkList.add(str); System.out.println(str); } bufReader.close(); bridgeStream.close(); r.close(); } FileOutputStream f=new FileOutputStream("C:/test.txt",true);//如果存在直接再添加,不存在创建新的文件 import java.io.*利用java的FileOutputStream类 新建个叫text的TXT文件,打印测试2个字import java.io.FileWriter;import java.io.IOException;import java.io.PrintWriter;public class Test { public static void main(String[] args) throws IOException { FileWriter fwl = new FileWriter("C:/text.txt", true); PrintWriter outl = new PrintWriter(fwl); outl.println("测试"); outl.close(); fwl.close(); }} 读写文本文件一般不使用OutputStream,而使用Writer, File File =new File("C:/test.txt"); try{ BufferedWriter buf = new BufferedWriter(new FileWriter(File)); buf.write("你好,试试看!"); buf.close(); } catch(IOException e){ } 测试帖!public class Test{ public static void main(String[] args){ Test t=new Test(); System.out.println(t.getNumberToRMB("2221.250")); } public String getNumberToRMB(String m){ String num = "零壹贰叁肆伍陆柒捌玖"; String dw = "圆拾佰仟万亿"; String mm[] = null; mm = m.split("\\."); String money = mm[0]; String result = num.charAt(Integer.parseInt("" + mm[1].charAt(0))) + "角" + num.charAt(Integer.parseInt("" + mm[1].charAt(1))) + "分"; for (int i = 0; i < money.length(); i++) { String str = ""; int n = Integer.parseInt(money.substring(money.length() - i - 1, money.length() - i)); str = str + num.charAt(n); if (i == 0) { str = str + dw.charAt(i); } else if ( (i + 4) % 8 == 0) { str = str + dw.charAt(4); } else if (i % 8 == 0) { str = str + dw.charAt(5); } else { str = str + dw.charAt(i % 4); } result = str + result; } result = result.replaceAll("零([^亿万圆角分])", "零"); result = result.replaceAll("亿零+万","亿零"); result = result.replaceAll("零+", "零"); result = result.replaceAll("零([亿万圆])", ""); result =result.replaceAll("壹拾","拾"); return result; }} import java.awt.*;import java.io.*;public class Test{ public static void main(String args[]) { double x=0.987; boolean b=true; try { PrintStream ps=new PrintStream(new FileOutputStream("test.txt")); ps.print(12345); ps.println("how are you"); ps.println(234); ps.println(x); ps.println(b); ps.close(); } catch (Exception e) { } }} 安装虚拟机老出错! 请各位大虾帮帮忙! 灵异事件啊,日期转换出了问题,那位帮我看看这诡异的代码吧 用javamail做过发邮件功能的进来帮忙看看这个问题!!! jsp还原sql数据库时遇到了问题! Mina IoSession.write问题 关于JFrame,Canvas边界的问题 为什么看不到结果? 锁定Vector类型,使其同一时刻只能有一个线程访问,怎么实现?? sun java platform的安装问题 编写一个JAVA桌面程序,该怎么开始 怎样把注释信息打入jar包(不打入源文件)?
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
public class Test {
public static void main(String args[]){
try {
FileOutputStream f=new FileOutputStream("C:/test.txt",true);
f.write("\r\n你好,this is a demo".getBytes());
f.close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
FileWriter fw = new FileWriter("c:\e.txt");
BufferedWriter bw = new BufferedWriter(fw);
bw.writer(out);
bw.flush();
bw.close();
return;}
FIle file=new File(path);
FileInputStream r=new FileInputStream(file);
InputStreamReader bridgeStream=new InputStreamReader(r);
BufferedReader bufReader=new BufferedReader(bridgeStream);
String str;
while((str=bufReader.readLine())!=null){
this.linkList.add(str);
System.out.println(str);
}
bufReader.close();
bridgeStream.close();
r.close();
}
FileOutputStream f=new FileOutputStream("C:/test.txt",true);//如果存在直接再添加,不存在创建新的文件
利用java的FileOutputStream类
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;public class Test {
public static void main(String[] args) throws IOException {
FileWriter fwl = new FileWriter("C:/text.txt", true);
PrintWriter outl = new PrintWriter(fwl);
outl.println("测试");
outl.close();
fwl.close();
}
}
BufferedWriter buf = new BufferedWriter(new FileWriter(File));
buf.write("你好,试试看!");
buf.close(); }
catch(IOException e){ }
Test t=new Test();
System.out.println(t.getNumberToRMB("2221.250"));
}
public String getNumberToRMB(String m){
String num = "零壹贰叁肆伍陆柒捌玖";
String dw = "圆拾佰仟万亿";
String mm[] = null;
mm = m.split("\\.");
String money = mm[0];
String result = num.charAt(Integer.parseInt("" + mm[1].charAt(0))) + "角" +
num.charAt(Integer.parseInt("" + mm[1].charAt(1))) + "分";
for (int i = 0; i < money.length(); i++) {
String str = "";
int n = Integer.parseInt(money.substring(money.length() - i - 1,
money.length() - i));
str = str + num.charAt(n);
if (i == 0) {
str = str + dw.charAt(i);
}
else if ( (i + 4) % 8 == 0) {
str = str + dw.charAt(4);
}
else if (i % 8 == 0) {
str = str + dw.charAt(5);
}
else {
str = str + dw.charAt(i % 4);
}
result = str + result;
}
result = result.replaceAll("零([^亿万圆角分])", "零");
result = result.replaceAll("亿零+万","亿零");
result = result.replaceAll("零+", "零");
result = result.replaceAll("零([亿万圆])", "");
result =result.replaceAll("壹拾","拾");
return result;
}
}
import java.io.*;
public class Test
{ public static void main(String args[])
{ double x=0.987;
boolean b=true;
try
{ PrintStream ps=new PrintStream(new FileOutputStream("test.txt"));
ps.print(12345);
ps.println("how are you");
ps.println(234);
ps.println(x);
ps.println(b);
ps.close();
}
catch (Exception e)
{
}
}
}