签名文件签名(java代码)

package encryptdecrypt;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.ObjectInputStream;import java.io.ObjectOutputStream;import java.security.KeyPair;import java.security.KeyPairGenerator;import java.security.PrivateKey;import java.security.PublicKey;import javax.swing.JFileChooser;import javax.swing.JFrame;import javax.swing.JMenu;import javax.swing.JMenuBar;import javax.swing.JMenuItem;import javax.swing.JOptionPane;import javax.swing.JScrollPane;import javax.swing.JTextArea;import javax.swing.ScrollPaneConstants;publicclass FileSignature {

/**

* @param args

*/publicstaticvoid main(String[ ] args) {// TODO Auto-generated method stub

DemoWindow5 dw = new DemoWindow5("文件签名");dw.setBounds(dw.getToolkit() .getScreenSize() .width / 3,dw.getToolkit()

.getScreenSize() .height / 3,dw.getToolkit() .getScreenSize() .width / 3,dw.getToolkit()

.getScreenSize() .height / 3);dw.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);dw.setVisible(true) ;

}

}classDemoWindow5extends JFrame implements ActionListener {JMenuBar menuBar = new JMenuBar();

JMenu fileMenu = new JMenu("文件");

JMenuItem openMenuItem = new JMenuItem("打开文件");

JMenuItem saveMenuItem = new JMenuItem("保存文件");

JMenu signMenu = new JMenu("签名验证");

JMenuItem generateItem = new JMenuItem("生成密钥对");JMenuItem signItem = new JMenuItem("签名文件") ;

JMenuItem validateItem = new JMenuItem("验证文件");

JTextArea jta = new JTextArea();intv = Sc rollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED;inth = Sc rollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED;JScrollPane jsp = new JScrollPane(jta, v, h) ;public DemoWindow5(String title) {super(title);fileMenu.add(openMenuItem);fileMenu.add(saveMenuItem);signMenu.add(generateItem);signMenu.add(signItem);signMenu.add(validateItem);menuBar.add(fileMenu);menuBar.add(signMenu);this.setJMenuBar(menuBar);add(jsp);openMenuItem.addActionListener(this);saveMenuItem.addActionListener(this);

generateItem.addActionListener(this);signItem.addActionListener(this);validateItem.addActionListener(this);

}publicvoid actionPerformed(ActionEvent e) {

// TODO Auto-generated method stubif (e.getSource() == openMenuItem) {openFile();

} elseif (e.getSource() == saveMenuItem) {saveFile();

} elseif (e.getSource() == generateItem) {generateKeys();

} elseif (e.getSource() == signItem) {sign();

} elseif (e.getSource() == validateItem) {validateSign();

}

}publicvoid openFile() {

String fileName = null;

// System.getProperty("user.dir")是获得用户当前的工作目录JFileChooser jfc = new

JFileChooser(System.getProperty("user.dir") ) ;jfc.setDialogTitle("打开文件");

//如果选中获取选择的文件的完整路径if (jfc.showOpenDialog(this) ==

J FileChooser.APPROVE_OPTION) {fileName = jfc.getSelectedFile() .getPath();

System.out.println(fileName);

}if (fileName == null)return;try {

FileInputStream fis = new FileInputStream(fileName);byte[ ] text = newbyte[f is.available()] ;f is.read(text);fis.close();

jta.setText(new String(text) );

} catch (Exception e1) {e1.printStackTrace();

}

}publicvoid saveFile() {

String fileName = null;

JFileChooser jfc = new

JFileChooser(System.getProperty("user.dir") ) ;jfc.setDialogTitle("保存文件");if (jfc.showSaveDialog(this) ==

J FileChooser.APPROVE_OPTION) {fileName = jfc.getSelectedFile() .getPath();

}if (fileName == null)return;try {

FileOutputStream fos = new FileOutputStream(fileName,false) ;fos.write(jta.getText() .getBytes()) ;fos.close();

} catch (Exception e1) {e1.printStackTrace();

}

}publicvoid generateKeys() {try {

String fileName = null;

JFileChooser jfc = new JFileChooser();jfc.setDialogTitle("生成密钥对");jfc.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);if (jfc.showSaveDialog(this) ==

J FileChooser.APPROVE_OPTION) {

fileName = jfc.getSelectedFile() .getPath();}if (fileName == null)return;

File file = new File(fileName);if ( !file.exists() ) {file.mkdir();

}

//创建DSA密钥对生成器

KeyPairGenerator keygen =

KeyPairGenerator.getInstance("DSA");

//采用1024位DSA密钥keygen.initialize(1024);

//得到密钥对

KeyPair keys = keygen.generateKeyPair();

PublicKey pubkey = keys.getPublic();

PrivateKey prikey = keys.getPrivate();

ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream(fileName + "/公钥.dat") );out.writeObject(pubkey);out.close();out = new ObjectOutputStream(new

FileOutputStream(fileName

+ "/私钥.dat") );out.writeObject(prikey);out.close();

} catch (Exception e1) {e1.printStackTrace();

}

}publicvoid sign() {try {

String fileName = null;

JFileChooser jfc = new JFileChooser();jfc.setDialogTitle( "导入私钥文件");

if (jfc.showOpenDialog(this) ==

J FileChooser.APPROVE_OPTION) {fileName = jfc.getSelectedFile() .getPath();}if (fileName == null)return;

//获取私钥

ObjectInputStream ois = new ObjectInputStream(newFileInputStream(f ileName) );

PrivateKey prikey = (PrivateKey) ois.readObject() ;//创建SHAlwithDSA签名类java.security.Signature dsa =java.security.Signature.getInstance(

"SHA1withDSA", "SUN");

//设置生成摘要的私钥dsa.initSign(prikey);

//对文本区的文本进行签名验证dsa.update(jta.getText() .getBytes( "UTF-8"));

//得到签名后的签名摘要值byte[ ] signText = dsa.sign();jfc = new JFileChooser();jfc.setDialogTitle("保存签名文件");if (jfc.showSaveDialog(this) ==

J FileChooser.APPROVE_OPTION) {fileName = jfc.getSelectedFile() .getPath();}if (fileName == null)return;

FileOutputStream fos = new FileOutputStream(fileName);fos.write(signText);fos.close();

} catch (Exception e1) {e1.printStackTrace();

}

}

publicvoid validateSign() {try {

String fileName = null;

JFileChooser jfc = new JFileChooser();jfc.setDialogTitle("导入公钥文件");if (jfc.showOpenDialog(this) ==

J FileChooser.APPROVE_OPTION) {fileName = jfc.getSelectedFile() .getPath();}if (fileName == null)return;

ObjectInputStream in = new ObjectInputStream(newFileInputStream(f ileName) );

PublicKey pubkey = (PublicKey) in.readObject();jfc = new JFileChooser();jfc.setDialogTitle("打开签名文件");if (jfc.showOpenDialog(this) ==

J FileChooser.APPROVE_OPTION) {fileName = jfc.getSelectedFile() .getPath();}if (fileName == null)return;

//从签名文件中读取签名摘要

FileInputStream fis = new FileInputStream(fileName);byte[ ] sigToVerfiy = newbyte[fis.available() ] ;f is.read(sigToVerf iy);fis.close();

//创建SHA1withDSA签名类java.security.Signature sig =java.security.Signature.getInstance(

"SHA1withDSA", "SUN");

//设置验证的公钥sig.initVerify(pubkey);

//验证文本区sig.update(jta.getText() .getBytes( "UTF-8"));

//显示验证信息

if (sig.verify(sigToVerfiy)) {

JOptionPane.showMessageDialog(null, "签名正确");} else {

JOptionPane.showMessageDialog(null, "签名不正确");}

} catch (Exception e1) {e1.printStackTrace();

}

}

}