public String getPaddingSchemeName() {
        return paddingSchemeName;
    }
Returns the cipher algorithm padding scheme name (as a String) to be used when constructing
{@link javax.crypto.Cipher Cipher} transformation string or {@code null} if the JCA Provider default mode for
the specified {@link #getAlgorithmName() algorithm} should be used.
<p/>
This attribute is used <em>only</em> when constructing the transformation string for block (byte array)
operations ({@link #encrypt(byte[], byte[])} and {@link #decrypt(byte[], byte[])}).  The
{@link #getStreamingPaddingSchemeName() streamingPaddingSchemeName} attribute is used when the block cipher is
used for streaming operations.
<p/>
The default value is {@code null} to retain the JCA Provider default.

@return the padding scheme name (as a String) to be used when constructing the
{@link javax.crypto.Cipher Cipher} transformation string, or {@code null} if the JCA Provider default
padding scheme for the specified {@link #getAlgorithmName() algorithm} should be used.
crypto/cipher/src/main/java/org/apache/shiro/crypto/cipher/DefaultBlockCipherService.java