Utils (corfu 0.2.3-11006 API)

java.lang.Object
- org.corfudb.util.Utils

```
public class Utils
extends Object
```
Created by crossbach on 5/22/15.

Field Summary

Fields
Modifier and Type Field and Description

static String SUN_JAVA_COMMAND
Sun property pointing the main class and its arguments.

Fields
Modifier and Type	Field and Description
`static String`	`SUN_JAVA_COMMAND` Sun property pointing the main class and its arguments.

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static String`	`bytesToHex(byte[] bytes)` Convert a byte array to a hex string.
`static String`	`convertToByteStringRepresentation(long value)` Convert to byte string representation.
`static Object`	`deserialize(ByteBuffer b)` Deserialize an object from a ByteBuffer.
`static Set<Long>`	`discretizeRange(com.google.common.collect.Range<Long> range)` Turn a range into a set of discrete longs.
`static Set<Long>`	`discretizeRangeSet(com.google.common.collect.RangeSet<Long> ranges)` Turn a set of ranges into a discrete set.
`static TailsResponse`	`getAllTails(Layout layout, CorfuRuntime runtime)` Fetches the max global log tail and all stream tails from the log unit cluster.
`static StreamsAddressResponse`	`getLogAddressSpace(Layout layout, CorfuRuntime runtime)` Retrieve the space of addresses of the log, i.e., for all streams in the log.
`static long`	`getLogTail(Layout layout, CorfuRuntime runtime)` Get global log tail.
`static <T> T`	`getOption(Map<String,Object> optionsMap, String option, Class<T> type)`
`static <T> T`	`getOption(Map<String,Object> optionsMap, String option, Class<T> type, T defaultValue)`
`static void`	`hexdump(byte[] bulk)` Hex dump contents of byte[] to stdout.
`static void`	`hexdump(io.netty.buffer.ByteBuf b)` Hex dump readable contents of ByteBuf to stdout.
`static String`	`insnToString(jdk.internal.org.objectweb.asm.tree.AbstractInsnNode insn)`
`static byte[]`	`intToBigEndianByteArray(int in)`
`static byte[]`	`longToBigEndianByteArray(long in)`
`static UUID`	`murmerhash3(UUID key, long seed)` murmer hash 3 implementation specialized for UUIDs, based on googlecode C implementation from: http://smhasher.googlecode.com/svn/trunk/MurmurHash3.cpp
`static UUID`	`nextDeterministicUuid(UUID uuid, long seed)`
`static long`	`parseLong(Object toParseObj)` A fancy parser which parses suffixes.
`static String`	`printByteCode(byte[] bytes)` Print byte code.
`static void`	`printLogAnatomy(CorfuRuntime runtime, ILogData logData)` Print the anatomy of a LogData
`static ByteBuffer`	`serialize(Object obj)` Serialize an object into a ByteBuffer.
`static UUID`	`simpleUUIDHash(UUID key, long seed)` simple UUID hashing, which is not hashing, and is effectively customized to the task of deterministically allocating new UUIDs based on a given UUID (which is necessary in the assignment of stream IDs in ICOrfuDBObjects that contain others, since syncing the log in multiple clients needs allocators to produce the same streamID/object every time).
`static String`	`toReadableId(UUID id)` Generates a human readable UUID string (4 hex chars) using time_mid.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - SUN_JAVA_COMMAND
```
public static final String SUN_JAVA_COMMAND
```
    Sun property pointing the main class and its arguments. Might not be defined on non Hotspot VM implementations.
    
    See Also:
    
    Constant Field Values
- Method Detail
  - bytesToHex
```
public static String bytesToHex(byte[] bytes)
```
    Convert a byte array to a hex string. Source: https://stackoverflow.com/questions/9655181/ how-to-convert-a-byte-array-to-a-hex-string-in-java
    
    Parameters:
    
    bytes - Byte array to convert
    
    Returns:
    
    Hex string representation.
  - intToBigEndianByteArray
```
public static byte[] intToBigEndianByteArray(int in)
```
  - longToBigEndianByteArray
```
public static byte[] longToBigEndianByteArray(long in)
```
  - printByteCode
```
public static String printByteCode(byte[] bytes)
```
    Print byte code.
    
    Parameters:
    
    bytes - Byte array that represents the byte code
    
    Returns:
    
    String representation of the byte code
  - insnToString
```
public static String insnToString(jdk.internal.org.objectweb.asm.tree.AbstractInsnNode insn)
```
  - parseLong
```
public static long parseLong(Object toParseObj)
```
    A fancy parser which parses suffixes.
    
    Parameters:
    
    toParseObj -
    
    Returns:
  - getOption
```
public static <T> T getOption(Map<String,Object> optionsMap,
                              String option,
                              Class<T> type,
                              T defaultValue)
```
  - getOption
```
public static <T> T getOption(Map<String,Object> optionsMap,
                              String option,
                              Class<T> type)
```
  - discretizeRange
```
public static Set<Long> discretizeRange(com.google.common.collect.Range<Long> range)
```
    Turn a range into a set of discrete longs.
    
    Parameters:
    
    range - The range to discretize.
    
    Returns:
    
    A set containing all the longs in that range.
  - discretizeRangeSet
```
public static Set<Long> discretizeRangeSet(com.google.common.collect.RangeSet<Long> ranges)
```
    Turn a set of ranges into a discrete set.
    
    Parameters:
    
    ranges - A set of ranges to discretize.
    
    Returns:
    
    A set containing all the longs in that rangeset.
  - convertToByteStringRepresentation
```
public static String convertToByteStringRepresentation(long value)
```
    Convert to byte string representation. from http://stackoverflow.com/questions/3758606/how-to-convert-byte-size-into-human-readable-format-in-java
    
    Parameters:
    
    value - The value to convert.
    
    Returns:
    
    A string for bytes (i.e, 10GB).
  - serialize
```
public static ByteBuffer serialize(Object obj)
```
    Serialize an object into a ByteBuffer.
    
    Parameters:
    
    obj - Object to serialize
    
    Returns:
    
    Buffer of the serialized object
  - deserialize
```
public static Object deserialize(ByteBuffer b)
```
    Deserialize an object from a ByteBuffer.
    
    Parameters:
    
    b - Buffer
    
    Returns:
    
    Deserialized object
  - hexdump
```
public static void hexdump(io.netty.buffer.ByteBuf b)
```
    Hex dump readable contents of ByteBuf to stdout.
    
    Parameters:
    
    b - ByteBuf with readable bytes available.
  - hexdump
```
public static void hexdump(byte[] bulk)
```
    Hex dump contents of byte[] to stdout.
    
    Parameters:
    
    bulk - Bytes.
  - murmerhash3
```
public static UUID murmerhash3(UUID key,
                               long seed)
```
    murmer hash 3 implementation specialized for UUIDs, based on googlecode C implementation from: http://smhasher.googlecode.com/svn/trunk/MurmurHash3.cpp
    
    Parameters:
    
    key - key to hash
    
    seed - hash seed
    
    Returns:
    
    hash of the key
  - simpleUUIDHash
```
public static UUID simpleUUIDHash(UUID key,
                                  long seed)
```
    simple UUID hashing, which is *not* hashing, and is effectively customized to the task of deterministically allocating new UUIDs based on a given UUID (which is necessary in the assignment of stream IDs in ICOrfuDBObjects that contain others, since syncing the log in multiple clients needs allocators to produce the same streamID/object every time).
    
    Parameters:
    
    key - key to hash
    
    seed - seed
    
    Returns:
    
    hash value
  - nextDeterministicUuid
```
public static UUID nextDeterministicUuid(UUID uuid,
                                         long seed)
```
  - toReadableId
```
public static String toReadableId(UUID id)
```
    Generates a human readable UUID string (4 hex chars) using time_mid.
    
    Parameters:
    
    id - The UUID to parse
    
    Returns:
    
    A human readable UUID string
  - printLogAnatomy
```
public static void printLogAnatomy(CorfuRuntime runtime,
                                   ILogData logData)
```
    Print the anatomy of a LogData
    Print how many streams are contained in the Metadata and how many entries per stream.
    Pretty useful for understanding how the the db is being used from the application perspective.
    
    Parameters:
    
    logData - Data entry to print
  - getLogTail
```
public static long getLogTail(Layout layout,
                              CorfuRuntime runtime)
```
    Get global log tail.
    
    Parameters:
    
    layout - Latest layout to query log tail from Log Unit
    
    runtime - Runtime
    
    Returns:
    
    Log global tail
  - getAllTails
```
public static TailsResponse getAllTails(Layout layout,
                                        CorfuRuntime runtime)
```
    Fetches the max global log tail and all stream tails from the log unit cluster. This depends on the mode of replication being used. CHAIN: Block on fetch of global log tail from the head log unit in every stripe. QUORUM: Block on fetch of global log tail from a majority in every stripe.
    
    Parameters:
    
    layout - Latest layout to get clients to fetch tails.
    
    Returns:
    
    The max global log tail obtained from the log unit servers.
  - getLogAddressSpace
```
public static StreamsAddressResponse getLogAddressSpace(Layout layout,
                                                        CorfuRuntime runtime)
```
    Retrieve the space of addresses of the log, i.e., for all streams in the log. This is typically used for sequencer recovery.
    
    Parameters:
    
    layout - latest layout.
    
    runtime - current runtime.
    
    Returns:
    
    response with all streams addresses and global log tail.

Class Utils

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

SUN_JAVA_COMMAND

Method Detail

bytesToHex

intToBigEndianByteArray

longToBigEndianByteArray

printByteCode

insnToString

parseLong

getOption

getOption

discretizeRange

discretizeRangeSet

convertToByteStringRepresentation

serialize

deserialize

hexdump

hexdump

murmerhash3

simpleUUIDHash

nextDeterministicUuid

toReadableId

printLogAnatomy

getLogTail

getAllTails

getLogAddressSpace