Date: 2016jan7
Update: 2025sep25
Language: Java
Level: novice
Q. Java: Get a file's size (in bytes)
A. Full example:
import java.io.File;
class Demo {
static long getSize(final String filename, final long defaultSize) {
if (filename == null) return defaultSize;
File file = new File(filename);
if (!file.exists()) return defaultSize;
return file.length();
}
public static final void main(String []args) {
final long size = getSize("/etc/passwd", -1);
if (size < 0) {
// Doesn't exist or not enough permission
}
System.out.println("size=" + size + " bytes");
}
}
Output (for me):
size=3666 bytes