Esempi di scrittura su file Java
In questo post vedremo cinque diversi esempi su come scrivere su un file utilizzando Java. Il codice sinppet controlla per vedere se il file esiste prima di scrivere nel file, altrimenti viene creato un file.
Scrivi su file usando BufferedWriter
import java.io.BufferedWriter; import java.io.File; import java.io.FileWriter; import java.io.IOException; public class WriteToFile {
public static void main( String[] args ) {
try {
String content = 'Content to write to file';
//Name and path of the file
File file = new File('writefile.txt');
if(!file.exists()){
file.createNewFile();
}
FileWriter fw = new FileWriter(file);
BufferedWriter bw = new BufferedWriter(fw);
bw.write(content);
bw.close();
} catch(IOException ex) {
System.out.println('Exception occurred:');
ex.printStackTrace();
}
} } Nota:Se vogliamo aggiungere a un file, dobbiamo inizializzare il file FileWriter con il vero parametro: FileWriter fw = new FileWriter(file, true); Relazionato:
Scrivi su file utilizzando PrintWriter
import java.io.*; public class WriteToFile {
public static void main( String[] args ) {
try {
String content = 'Content to write to file';
//Name and path of the file
File file = new File('writefile.txt');
if(!file.exists()){
file.createNewFile();
}
FileWriter fw = new FileWriter(file);
PrintWriter bw = new PrintWriter(fw);
bw.write(content);
bw.close();
} catch(IOException ex) {
System.out.println('Exception occurred:');
ex.printStackTrace();
}
} } Scrivi su file utilizzando FileOutputStream
import java.io.File; import java.io.FileOutputStream; import java.io.IOException; public class WriteToFile {
public static void main( String[] args ) {
try {
String content = 'Content to write to file';
//Name and path of the file
File file = new File('writefile.txt');
if(!file.exists()){
file.createNewFile();
}
FileOutputStream outStream = new FileOutputStream(file);
byte[] strToBytes = content.getBytes();
outStream.write(strToBytes);
outStream.close();
} catch(IOException ex) {
System.out.println('Exception occurred:');
ex.printStackTrace();
}
} } Scrivi su file usando la classe Files
import java.io.IOException; import java.nio.file.Files; import java.nio.file.Path; import java.nio.file.Paths; public class WriteToFile {
public static void main( String[] args ) {
Path path = Paths.get('writefile.txt');
String content = 'Content to write to file';
try {
byte[] bytes = content.getBytes();
Files.write(path, bytes);
} catch(IOException ex) {
System.out.println('Exception occurred:');
ex.printStackTrace();
}
} } Scrivi su file utilizzando DataOutputStream
import java.io.*; public class WriteToFile {
public static void main( String[] args ) {
String content = 'Content to write to file';
try {
File file = new File('writefile.txt');
if(!file.exists()){
file.createNewFile();
}
FileOutputStream fos = new FileOutputStream(file);
BufferedOutputStream bos = new BufferedOutputStream(fos);
DataOutputStream dataOutStream = new DataOutputStream(bos);
dataOutStream.writeUTF(content);
dataOutStream.close();
} catch(IOException ex) {
System.out.println('Exception occurred:');
ex.printStackTrace();
}
} }
