content: package net.minecraft.network;
  
  import io.netty.buffer.ByteBuf;
  import io.netty.channel.ChannelHandlerContext;
  
  import javax.crypto.Cipher;
  import javax.crypto.ShortBufferException;
  
  public class NettyEncryptionTranslator {
      private final Cipher cipher;
      private byte[] field_150505_b = new byte[0];
      private byte[] field_150506_c = new byte[0];
  
      protected NettyEncryptionTranslator(Cipher cipherIn) {
          this.cipher = cipherIn;
      }
  
      private byte[] func_150502_a(ByteBuf buf) {
          int i = buf.readableBytes();
  
          if (this.field_150505_b.length < i) {
              this.field_150505_b = new byte[i];
          }
  
          buf.readBytes(this.field_150505_b, 0, i);
          return this.field_150505_b;
      }
  
      protected ByteBuf decipher(ChannelHandlerContext ctx, ByteBuf buffer) throws ShortBufferException {
          int i = buffer.readableBytes();
          byte[] abyte = this.func_150502_a(buffer);
          ByteBuf bytebuf = ctx.alloc().heapBuffer(this.cipher.getOutputSize(i));
          bytebuf.writerIndex(this.cipher.update(abyte, 0, i, bytebuf.array(), bytebuf.arrayOffset()));
          return bytebuf;
      }
  
      protected void cipher(ByteBuf in, ByteBuf out) throws ShortBufferException {
          int i = in.readableBytes();
          byte[] abyte = this.func_150502_a(in);
          int j = this.cipher.getOutputSize(i);
  
          if (this.field_150506_c.length < j) {
              this.field_150506_c = new byte[j];
          }
  
          out.writeBytes(this.field_150506_c, 0, this.cipher.update(abyte, 0, i, this.field_150506_c));
      }
  }
  