ファイルに追記する方法

String fileName = "C:\\file.txt";
//fileName\使\\
void setup() {
writer = createWriter();//
}
void draw() {
for (int a=0;a<10;a++) {
write(str(a)+",");//write()
}
flush();//flushwrite()
}
//==========
BufferedWriter writer;
BufferedWriter createWriter() {
try {
writer = new BufferedWriter(new FileWriter(fileName, true));
}
catch (IOException ioe) {
println("error: " + ioe);
}
return writer;
}
void write(String string) {//()
try {
writer.write(string);
}
catch (IOException ioe) {
println("error: " + ioe);
}
}
void flush() {//
try {
writer.flush();
}
catch (IOException ioe) {
println("error: " + ioe);
}
}
void close() {//
try {
writer.flush();
writer.close();
}
catch (IOException ioe) {
println("error: " + ioe);
}
}
//==========
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