jsp java 소스코드 빌드할때 질문드립니다.

package com.keehl;
import java.io.UnsupportedEncodingException;
import java.security.InvalidAlgorithmParameterException;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.NoSuchAlgorithmException;
 
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import org.apache.tomcat.util.codec.binary.Base64;
 
 
public class AES256Util {
  private String iv;
  private Key keySpec;
 
  public AES256Util(String key) throws UnsupportedEncodingException {
    this.iv = key.substring(0, 16);
 
    byte[] keyBytes = new byte[16];
    byte[] b = key.getBytes("UTF-8");
    int len = b.length;
    if (len > keyBytes.length) {
      len = keyBytes.length;
    }
    System.arraycopy(b, 0, keyBytes, 0, len);
    SecretKeySpec keySpec = new SecretKeySpec(keyBytes, "AES");
 
    this.keySpec = keySpec;
  }
 
 
  // 암호화
  public String aesEncode(String str) throws java.io.UnsupportedEncodingException,
      NoSuchAlgorithmException,
      NoSuchPaddingException,
      InvalidKeyException,
      InvalidAlgorithmParameterException,
      IllegalBlockSizeException,
      BadPaddingException {
    Cipher c = Cipher.getInstance("AES/CBC/PKCS5Padding");
    c.init(Cipher.ENCRYPT_MODE, keySpec, new IvParameterSpec(iv.getBytes()));
 
    byte[] encrypted = c.doFinal(str.getBytes("UTF-8"));
    String enStr = new String(Base64.encodeBase64(encrypted));
 
    return enStr;
  }
 
  //복호화
  public String aesDecode(String str) throws java.io.UnsupportedEncodingException,
      NoSuchAlgorithmException,
      NoSuchPaddingException,
      InvalidKeyException,
      InvalidAlgorithmParameterException,
      IllegalBlockSizeException,
      BadPaddingException {
    Cipher c = Cipher.getInstance("AES/CBC/PKCS5Padding");
    c.init(Cipher.DECRYPT_MODE, keySpec, new IvParameterSpec(iv.getBytes("UTF-8")));
 
    byte[] byteStr = Base64.decodeBase64(str.getBytes());
 
    return new String(c.doFinal(byteStr),"UTF-8");
  }
 
}

javac -cp commons-codec-1.7.jar -d d:\workspace\eclipse-workspace\myhomepage\WebContent\classes AES256Util.java -encoding utf-8