IO operation with Java

BufferedReader

package PBO.IO.Reader;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;

public class ReaderTest {
    public static void main(String[] args) {
        try {
            BufferedReader reader = new BufferedReader(new FileReader("baca.txt"));
            String line;
            while((line = reader.readLine()) != null) {
                System.out.println(line);
            }
            reader.close();
        } catch (FileNotFoundException ex) {
            Logger.getLogger(ReaderTest.class.getName()).log(Level.SEVERE, "file tidak ditemukan", ex);
        } catch (IOException ex) {
            Logger.getLogger(ReaderTest.class.getName()).log(Level.SEVERE, "kesalahan IO", ex);
        }
    }
}

BufferedWriter

package PBO.IO.Writer;

import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;

public class WriterTest {

    public static void main(String[] args) {
        try {
            BufferedWriter writer = new BufferedWriter(new FileWriter("newfile.txt"));
            writer.write("ini baris pertama\n");
            writer.flush();

            writer.write("ini baris kedua\n");
            writer.write("ini baris ketiga\n");
            writer.close();
        } catch (IOException ex) {
            Logger.getLogger(WriterTest.class.getName()).log(Level.SEVERE, null, ex);
        } finally {
            System.out.println("tulis file selesai");
        }
    }
}

ImageIO

package PBO.IO.ImageIO;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.util.logging.Logger;
import javax.imageio.ImageIO;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JOptionPane;

public class ImageTest {

    private static final Logger LOGGER = Logger.getLogger(ImageTest.class.getName());
    
    public static void main(String[] args) {
        try {
            URL url = new URL("https://www.gravatar.com/avatar/7d48e514e24de81806f4660759fbe7fb?s=256&d=identicon&r=PG");
            URLConnection urlcon = url.openConnection();

            InputStream is = urlcon.getInputStream();
            OutputStream os = new FileOutputStream("gambar.jpg");
            
            int byteRead;
            do {
                byteRead = is.read();
                os.write(byteRead);
            } while (byteRead != -1);
            LOGGER.info("ambil data dari stream");
            
            os.flush();
            os.close();
            is.close();

            //tampilkan gambar
            Icon icon = new ImageIcon(ImageIO.read(new File("gambar.jpg")));
            JOptionPane.showMessageDialog(null, null, "menampilkan gambar",
                    JOptionPane.INFORMATION_MESSAGE, icon);
            LOGGER.info("menampilkan gambar");

        } catch (MalformedURLException ex) {
            LOGGER.severe("malform url masbro..");
        } catch (IOException ex) {
            LOGGER.severe("kesalahan input output masbro..");
        }
    }
}

InputStream

package PBO.IO.InputStream;

import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.util.logging.Level;
import java.util.logging.Logger;

public class InputStreamTest {

    public static void main(String[] args) {
        try {
            URL url = new URL("http://www.yahoo.com");
            URLConnection urlconn = url.openConnection();
            InputStream is = urlconn.getInputStream();

            int byteRead;
            do {
                byteRead = is.read();
                System.out.println((char) byteRead);
            } while (byteRead != -1);

        } catch (MalformedURLException ex) {
            Logger.getLogger(InputStreamTest.class.getName()).log(Level.SEVERE, null, ex);
        } catch (IOException ex) {
            Logger.getLogger(InputStreamTest.class.getName()).log(Level.SEVERE, null, ex);
        }
        
    }
}

IOFile

package PBO.IO.File;

import java.io.File;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;

public class FileTest {
    public static void main(String[] args) {
        File f = new File("newfile.txt");
        if(!f.exists()) {
            try {
                f.createNewFile();
                System.out.println(f.getAbsolutePath());
            } catch (IOException ex) {
                Logger.getLogger(FileTest.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
        
        File folder = new File("newfolder");
        if(!folder.exists()) {
            folder.mkdir();
            //f.mkdirs(); //membuat folder dalam folder
        }
        
        File currentFolder = new File(System.getProperty("user.dir"));
        File[] siblings = currentFolder.listFiles();
        
        for (File sibling : siblings) {
            if(sibling.isFile()) {
                System.out.println("file        : " + sibling.getName());
            } else {
                System.out.println("directory   : " + sibling.getName());
            }
        }
    }
}

OutputStream

package PBO.IO.OutputStream;

import PBO.IO.InputStream.InputStreamTest;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.util.logging.Level;
import java.util.logging.Logger;

public class OutputStreamTest {

    public static void main(String[] args) {
        try {
            URL url = new URL("http://www.google.com");
            URLConnection urlconn = url.openConnection();
            InputStream is = urlconn.getInputStream();
            OutputStream os = new FileOutputStream("google.txt");

            int byteRead;
            do {
                byteRead = is.read();
                os.write(byteRead);
                System.out.println((char) byteRead);
            } while (byteRead != -1);

            os.close();
        } catch (MalformedURLException ex) {
            Logger.getLogger(InputStreamTest.class.getName()).log(Level.SEVERE, null, ex);
        } catch (IOException ex) {
            Logger.getLogger(InputStreamTest.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}