| Name | Description | Type | Package | Framework |
| ByteArray | this class is a experimental replacement of byte[]. | Class | net.yacy.cora.util | Yacy |
| ByteBuffer | Class | net.yacy.cora.util | Yacy | |
| CommonPattern | This class provides Pattern constants to be used to replace a regex in s. | Class | net.yacy.cora.util | Yacy |
| ConcurrentLog | jdk-based logger tend to block at java. | Class | net.yacy.cora.util | Yacy |
| ConcurrentLog .Message | Class | net.yacy.cora.util | Yacy | |
| ConcurrentLog .Worker | Class | net.yacy.cora.util | Yacy | |
| JSONArray | A JSONArray is an ordered sequence of values. | Class | net.yacy.cora.util | Yacy |
| JSONException | Class | net.yacy.cora.util | Yacy | |
| JSONObject | A JSONObject is an unordered collection of name/value pairs. | Class | net.yacy.cora.util | Yacy |
| JSONObject .Null | JSONObject. | Class | net.yacy.cora.util | Yacy |
| JSONTokener | Class | net.yacy.cora.util | Yacy | |
| LookAheadIterator | convenience class for iterator implementations that naturally terminate when the next() method would return null. | Class | net.yacy.cora.util | Yacy |
| Memory | Class | net.yacy.cora.util | Yacy | |
| NumberTools | Class | net.yacy.cora.util | Yacy | |
| SpaceExceededException | Class | net.yacy.cora.util | Yacy | |
| StringBuilderComparator | case-insensitive compare of two StringBuilder objects this shall replace the corresponding method in class String when StringBuilder objects are not transformed into string | Class | net.yacy.cora.util | Yacy |