package com.atlassian.cache.vcache;
   
   import java.io.ByteArrayOutputStream;
   import java.io.IOException;
   import java.io.ObjectOutputStream;
   import java.io.Serializable;
   import java.util.Base64;
   import java.util.UUID;
   import javax.annotation.Nonnull;
  import javax.annotation.Nullable;
  
  import com.atlassian.cache.CacheException;
  
  class Utils
  {
      @Nonnull
      static String asString(@Nullable Object key)
      {
          if (key == null)
          {
              throw new CacheException("key cannot be null");
          }
  
          if (key instanceof String)
          {
              return (String) key;
          }
  
          if (key instanceof Serializable)
          {
              final ByteArrayOutputStream baos = new ByteArrayOutputStream();
              try (ObjectOutputStream oos = new ObjectOutputStream(baos))
              {
                  oos.writeObject(key);
              }
              catch (IOException ioe)
              {
                  throw new CacheException("Unable to convert key to String using serialization", ioe);
              }
              return Base64.getEncoder().encodeToString(baos.toByteArray());
          }
  
          throw new CacheException("Key of type " + key.getClass().getName() + " is not supported");
      }
  
      @Nonnull
      static Serializable asSerializable(Object value)
      {
          //noinspection ConstantConditions
          if (value == null)
          {
              throw new CacheException("value cannot be null");
          }
  
          if (value instanceof Serializable)
          {
              return (Serializable) value;
          }
  
          throw new CacheException("Value of type " + value.getClass().getName() + " is not supported");
      }
  
      @Nonnull
      static String uniqueId()
      {
          return UUID.randomUUID().toString();
      }
  }