Admin: 1 версия

2010-06-01T05:19:27Z

1 версия

в 17:44, 31 мая 2010

2010-05-31T17:44:27Z

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== Append or add some contents to the file ==



<source lang="java">
import java.io.File;
import java.io.FileWriter;
public class Main {
public static void main(String[] args) throws Exception{
File file = new File("user.txt");
FileWriter writer = new FileWriter(file, true);
writer.write("username=java;password=secret" + System.getProperty("line.separator"));
writer.flush();
writer.close();
}
}</source>



== FileWriter ==

<OL><LI>FileWriter provides a convenient way of writing characters to a file.</LI><LI>FileWriter uses your computer"s default character encoding.</LI></OL>



<source lang="java">
public FileWriter (File file)
public FileWriter (File file, boolean append)
public FileWriter (String path)
public FileWriter (String path, boolean append)
public FileWriter (FileDescriptor fileDescriptor)</source>



== Use FileWriter to write an array of strings to a file. ==



<source lang="java">
import java.io.FileWriter;
public class Main {
public static void main(String[] argv) throws Exception {
FileWriter fw = new FileWriter("file.dat");
String strs[] = { "com", "exe", "doc" };
for (int i = 0; i < strs.length; i++) {
fw.write(strs[i] + "\n");
}
fw.close();
}
}</source>



== Wrap FileWriter with BufferedWriter ==



<source lang="java">
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
public class AllCapsDemo {
public static void main(String[] arguments) {
String sourceName = "asdf";
try {
File source = new File(sourceName);
File temp = new File("cap" + sourceName + ".tmp");
FileReader fr = new FileReader(source);
BufferedReader in = new BufferedReader(fr);
FileWriter fw = new FileWriter(temp);
BufferedWriter out = new BufferedWriter(fw);
boolean eof = false;
int inChar = 0;
do {
inChar = in.read();
if (inChar != -1) {
char outChar = Character.toUpperCase((char) inChar);
out.write(outChar);
} else
eof = true;
} while (!eof);
in.close();
out.close();
boolean deleted = source.delete();
if (deleted)
temp.renameTo(source);
} catch (Exception se) {
System.out.println("Error - " + se.toString());
}
}
}</source>

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Java Tutorial/File/FileWriter - История изменений

Admin: 1 версия

в 17:44, 31 мая 2010