我正在尝试加密然后解密回Java中的文件。我正在使用 Eclipse IDE。该程序似乎工作正常，只是计时器没有按预期工作。我使用两个计时器分别计算加密和解密时间。以毫秒为单位的解密时间显示为 0。Eclipse 说：
java.security.InvalidKeyException: No installed provider supports this key: (null)
at javax.crypto.Cipher.a(DashoA13*..)
at javax.crypto.Cipher.init(DashoA13*..)
at javax.crypto.Cipher.init(DashoA13*..)
at AES.<init>(AES.java:133)
at AES.action(AES.java:311)
at java.awt.Component.handleEvent(Component.java:6543)
at java.awt.Component.postEvent(Component.java:4956)
at java.awt.Component.postEvent(Component.java:4966)
at java.awt.Component.dispatchEventImpl(Component.java:4676)
at java.awt.Component.dispatchEvent(Component.java:4488)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:674)
at java.awt.EventQueue.access$400(EventQueue.java:81)
at java.awt.EventQueue$2.run(EventQueue.java:633)
at java.awt.EventQueue$2.run(EventQueue.java:631)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:98)
at java.awt.EventQueue$3.run(EventQueue.java:647)
at java.awt.EventQueue$3.run(EventQueue.java:645)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:644)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
我特此发布我的整个代码：
import java.awt.*;
import javax.swing.JFileChooser;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.CipherInputStream;
import javax.crypto.CipherOutputStream;
import javax.crypto.KeyGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.spec.AlgorithmParameterSpec;
public class AES extends java.applet.Applet {
Label encry = new Label("Choose Algorithm: ");
Choice textAlignment = new Choice();
TextField TextFieldName = new TextField("", 10);
TextField TextFieldName2 = new TextField("", 10);
Image I;
Label label;
Label label2;
private static JFileChooser fc;
// for AES
Cipher ecipher;
Cipher dcipher;
// for BlowFish
private static String cipher_key = "Blowfish";
private static Cipher cipher;
private static KeyGenerator k_generator;
private static SecretKey secret_key;
private long startTime = 0;
private long stopTime = 0;
private boolean running = false;
public void start() {
this.startTime = System.currentTimeMillis();
this.running = true;
}
public void stop() {
this.stopTime = System.currentTimeMillis();
this.running = false;
}
//elaspsed time in milliseconds
public long getElapsedTime() {
long elapsed;
if (running) {
elapsed = (System.currentTimeMillis() - startTime);
}
else {
elapsed = (stopTime - startTime);
}
return elapsed;
}
private long startTime2 = 0;
private long stopTime2 = 0;
private boolean running2 = false;
public void start2() {
this.startTime2 = System.currentTimeMillis();
this.running2 = true;
}
public void stop2() {
this.stopTime2 = System.currentTimeMillis();
this.running2 = false;
}
//elaspsed time in milliseconds
public long getElapsedTime2() {
long elapsed;
if (running2) {
elapsed = (System.currentTimeMillis() - startTime2);
}
else {
elapsed = (stopTime2 - startTime2);
}
return elapsed;
}
public AES(SecretKey key)
{
// Create an 8-byte initialization vector
byte[] iv = new byte[]
{
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
};
AlgorithmParameterSpec paramSpec = new IvParameterSpec(iv);
try
{
ecipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
dcipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
// CBC requires an initialization vector
ecipher.init(Cipher.ENCRYPT_MODE, key, paramSpec);
dcipher.init(Cipher.DECRYPT_MODE, key, paramSpec);
}
catch (Exception e)
{
e.printStackTrace();
}
}
// Buffer used to transport the bytes from one stream to another
static byte[] buf = new byte[1024];
public void encrypt(InputStream in, OutputStream out)
{
try
{
// Bytes written to out will be encrypted
out = new CipherOutputStream(out, ecipher);
// Read in the cleartext bytes and write to out to encrypt
int numRead = 0;
while ((numRead = in.read(buf)) >= 0)
{
out.write(buf, 0, numRead);
}
out.close();
}
catch (java.io.IOException e)
{
}
}
public void decrypt(InputStream in, OutputStream out)
{
try
{
// Bytes read from in will be decrypted
in = new CipherInputStream(in, dcipher);
// Read in the decrypted bytes and write the cleartext to out
int numRead = 0;
while ((numRead = in.read(buf)) >= 0)
{
out.write(buf, 0, numRead);
}
out.close();
}
catch (java.io.IOException e)
{
}
}
// for BlowFish encryption
public void encrypt_data(InputStream in, OutputStream out) throws InvalidKeyException, IOException
{
//initialize the cipher for decryption
cipher.init(Cipher.ENCRYPT_MODE, secret_key);
// Bytes written to out will be encrypted
out = new CipherOutputStream(out, cipher);
// Read in the cleartext bytes and write to out to encrypt
int numRead = 0;
while ((numRead = in.read(buf)) >= 0)
{
out.write(buf, 0, numRead);
}
out.close();
}
//for BlowFish decryption
public void decrypt_data(InputStream in, OutputStream out) throws InvalidKeyException, IOException {
// initialize the cipher once again
cipher.init(Cipher.DECRYPT_MODE, secret_key);
// Bytes read from in will be decrypted
in = new CipherInputStream(in, cipher);
int numRead = 0;
while ((numRead = in.read(buf)) >= 0)
{
out.write(buf, 0, numRead);
}
out.close();
}
public AES() {
setLayout(new FlowLayout());
//simpleMethod();
}
public void init() {
I=getImage(getCodeBase(),"lock.png");
add(encry);
label = new Label("Encryption Time ", Label.RIGHT);
label2 = new Label("Decryption Time ", Label.RIGHT);
//Add 4 different options to it:
textAlignment.add("AES");
textAlignment.add("BlowFish");
textAlignment.add("PBE");
//Then add the drop down list to the screen
add(textAlignment);
add(label);
add(TextFieldName);
add(label2);
add(TextFieldName2);
}
//AES button caused the event
public boolean action(Event event, Object object) {
if (event.target == textAlignment) {
String selection = textAlignment.getSelectedItem();
if (fc == null) {
fc = new JFileChooser(".");
}
// Show it.
int returnVal = fc.showOpenDialog(this);
if (returnVal == JFileChooser.APPROVE_OPTION) {
if (selection.equals("AES")){
AES s1 = new AES();
s1.start(); // timer start
KeyGenerator kgen;
try {
kgen = KeyGenerator.getInstance("AES");
kgen.init(128);
SecretKey key = kgen.generateKey();
// Create encrypter/decrypter class
// Create encrypter/decrypter class
AES encrypter = new AES(key);
try {
encrypter.encrypt(new FileInputStream(fc.getSelectedFile().getPath()),new FileOutputStream("C:/Users/Acer/Desktop/encrypted"));
s1.stop(); // timer stops
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
AES s2 = new AES();
// Decrypt
try {
s2.start2(); // timer starts
encrypter.decrypt(new FileInputStream("C:/Users/Acer/Desktop/encrypted"),new FileOutputStream("C:/Users/Acer/Desktop/decrypted"));
s2.stop2(); // timer stops
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
TextFieldName.setText(Long.toString(s1.getElapsedTime()));
TextFieldName2.setText(Long.toString(s2.getElapsedTime2())); }
catch (NoSuchAlgorithmException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
}
if (selection.equals("BlowFish")){
AES s1 = new AES();
AES s2 = new AES();
AES encryption = new AES(secret_key);
s1.start(); // timer start
//Generate encryption key based on codecypherkey code word
try {
k_generator = KeyGenerator.getInstance(cipher_key);
} catch (NoSuchAlgorithmException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
//Create a secret key
secret_key = k_generator.generateKey();
//Create Cipher based on the previous encryption key code
try {
cipher = Cipher.getInstance(cipher_key);
} catch (NoSuchAlgorithmException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (NoSuchPaddingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
encryption.encrypt_data(new FileInputStream(fc.getSelectedFile().getPath()),new FileOutputStream("C:/Users/Acer/Desktop/encrypted"));
s1.stop(); // timer stops
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InvalidKeyException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
s2.start();
encryption.decrypt_data(new FileInputStream("C:/Users/Acer/Desktop/encrypted"),new FileOutputStream("C:/Users/Acer/Desktop/decrypted"));
s2.stop();
TextFieldName.setText(Long.toString(s1.getElapsedTime()));
TextFieldName2.setText(Long.toString(s2.getElapsedTime2()));
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InvalidKeyException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
return running;
}
public void paint(Graphics g)
{
g.drawImage(I,10,10,this);
}}
谢谢你的耐心。