import java.text.*;
import java.util.*;
import java.io.*;
public class FormatDateTime {
public static String read(String fileName)throws IOException{
StringBuffer sb=new StringBuffer();
BufferedReader in=new BufferedReader(new FileReader(fileName));
String s;
while((s=in.readLine())!=null){
sb.append(s);
sb.append("\n");
}
in.close();
return sb.toString();
}
public static void write(String fileName,String text)throws IOException{
PrintWriter out=new PrintWriter(new BufferedWriter(new FileWriter(fileName)));
out.print(text);
out.close();
}
public static void main(String[] args)throws Exception {
String change=read(args[0]);
List list=Arrays.asList(change.split("\n"));
SimpleDateFormat from=new SimpleDateFormat("yyyy-MM-dd");
SimpleDateFormat to=new SimpleDateFormat("yyyyMMdd");
try{
for(int i=0;i<list.size();i++){
Date temp=from.parse((String)list.get(i));
String changed=to.format(temp);
write(args[1],changed);
}
}catch(Exception e){}
}
}
import java.util.*;
import java.io.*;
public class FormatDateTime {
public static String read(String fileName)throws IOException{
StringBuffer sb=new StringBuffer();
BufferedReader in=new BufferedReader(new FileReader(fileName));
String s;
while((s=in.readLine())!=null){
sb.append(s);
sb.append("\n");
}
in.close();
return sb.toString();
}
public static void write(String fileName,String text)throws IOException{
PrintWriter out=new PrintWriter(new BufferedWriter(new FileWriter(fileName)));
out.print(text);
out.close();
}
public static void main(String[] args)throws Exception {
String change=read(args[0]);
List list=Arrays.asList(change.split("\n"));
SimpleDateFormat from=new SimpleDateFormat("yyyy-MM-dd");
SimpleDateFormat to=new SimpleDateFormat("yyyyMMdd");
try{
for(int i=0;i<list.size();i++){
Date temp=from.parse((String)list.get(i));
String changed=to.format(temp);
write(args[1],changed);
}
}catch(Exception e){}
}
}
改为:
PrintWriter out=new PrintWriter(new BufferedWriter(new FileWriter(fileName,true)));
这样才是每次加到文件尾部;