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import java.io.*;

class DecToBin{
    public static void main(String[] args) throws IOException{
        //変数宣言
        int[] nisin = new int[16];

        //入力
        System.out.print("10進数を入力：");
        BufferedReader br =
            new BufferedReader(new InputStreamReader(System.in));
        int jyu = Integer.parseInt(br.readLine());

        //変換
        for(int i=0; i<16; i++){
            nisin[i] = jyu % 2;	
            jyu = jyu / 2;
        }
        
        //出力
        for(int i=16-1; i>=0; i--){
            System.out.print(nisin[i]);
        }
    }
}

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//<applet code="DecToBinApplet" width="200" height="40"></applet>
import java.awt.*;
import java.awt.event.*;
import java.applet.*;

public class DecToBinApplet
        extends Applet implements ActionListener{
    private Button     btTrance;  //変換ボタン
    private TextField  txtDec;    //10進数の入力欄
    private Label      lblBin;    //2進数の表示
    private Panel      pl;        //パネル

    public void init(){
        txtDec   = new TextField();
        lblBin   = new Label("");
        btTrance = new Button("実行");
        pl       = new Panel();

        setBackground(new Color(255,255,255));

        //レイアウトの設定
        setLayout(null);
        pl.setLayout(null);

        //座標の設定
        txtDec.setBounds(0, 0,  100, 20);
        btTrance.setBounds  (100, 0, 100, 20);
        lblBin.setBounds (0, 20, 200, 20);
        pl.setBounds(0, 0 ,500, 100);

        //パネルにコントロールを配置
        pl.add(txtDec);
        pl.add(btTrance);
        pl.add(lblBin);

        add(pl);  //パネルをアプレットに配置

        btTrance.addActionListener(this);
    }

    public void actionPerformed(ActionEvent e){
        if(e.getSource() == btTrance){
            //変数宣言
            int[] nisin = new int[16];          

            //入力
            int jyu=Integer.parseInt(txtDec.getText());

            //変換
            for(int i=0; i<16; i++){
                nisin[i] = jyu % 2;
                jyu = jyu / 2;
            }

            //出力
            lblBin.setText("");
            for(int i=16-1; i>=0; i--){
                lblBin.setText(lblBin.getText() + nisin[i]);
            }
        }
    }
}