File f = new File("hoge/piyo/fuga.txt"); if(f.exist()){ //存在する }
System.out.println(new File(".").getAbsoluteFile().getParent());
File f = new File("/hoge/piyo/fuga/aaa.jpg"); System.out.println(f.getName());
import org.apache.commons.io.FileUtils;
byte[] b = FileUtils.readFileToByteArray(f);