# Package org.h2.util

Internal utility classes.

See: Description

Interface Summary
Cache: The cache keeps frequently used objects in the main memory.
CacheWriter: The cache writer is called by the cache to persist changed data that needs to be removed from the cache.
HasSQL: An object that has an SQL representation.
Utils.ClassFactory: The utility methods will try to use the provided class factories to convert binary name of class to Class object.

Class Summary
AbbaDetector: Utility to detect AB-BA deadlocks.
AbbaLockingDetector: Utility to detect AB-BA deadlocks.
Bits: Manipulations with bytes and arrays.
ByteStack: The stack of byte values.
CacheHead: The head element of the linked list.
CacheLRU: A cache implementation based on the last recently used (LRU) algorithm.
CacheObject: The base object for all cached objects.
CacheTQ: An alternative cache implementation.
CloseWatcher: A phantom reference to watch for unclosed objects.
DateTimeUtils: This utility class contains time conversion functions.
DbDriverActivator: The driver activator loads the H2 driver when starting the bundle.
DebuggingThreadLocal<T>: Similar to ThreadLocal, except that it allows its data to be read from other threads - useful for debugging info.
IntArray: An array with integer element.
IntervalUtils: This utility class contains interval conversion functions.
IOUtils: This utility class contains input/output functions.
JdbcUtils: This is a utility class with JDBC helper functions.
JSR310Utils: This utility class provides access to JSR 310 classes.
LegacyDateTimeUtils: Date and time utilities for `Date`, `Time`, and `Timestamp` classes.
MathUtils: This is a utility class with mathematical helper functions.
MemoryEstimator: Class MemoryEstimator.
MemoryUnmapper: Unsafe memory unmapper.
NetUtils: This utility class contains socket helper functions.
NetworkConnectionInfo: Network connection information.
OsgiDataSourceFactory: This class implements the OSGi DataSourceFactory interface for the H2 JDBC driver.
ParserUtil
Permutations<T>: A class to iterate over all permutations of an array.
Profiler: A simple CPU profiling tool similar to java -Xrunhprof.
ScriptReader: This class can split SQL scripts to single SQL statements.
SimpleColumnInfo: Metadata of a column.
SmallLRUCache<K,V>: This class implements a small LRU object cache.
SmallMap: A simple hash table with an optimization for the last recently used object.
SoftValuesHashMap<K,V>: Map which stores items using SoftReference.
SortedProperties: Sorted properties file.
SourceCompiler: This class allows to convert source code to a class.
StringUtils: A few String utility functions.
Task: A method call that is executed in a separate thread.
TempFileDeleter: This class deletes temporary files when they are not used any longer.
ThreadDeadlockDetector: Detects deadlocks between threads.
TimeZoneProvider: Provides access to time zone API.
Tool: Command line tools implement the tool interface so that they can be used in the H2 Console.
Utils: This utility class contains miscellaneous functions.
Utils10: Utilities with specialized implementations for Java 10 and later versions.

## Package org.h2.util Description

Internal utility classes.