com.google.instrumentation.trace

Class TraceId

java.lang.Object

com.google.instrumentation.trace.TraceId

All Implemented Interfaces:

Comparable<TraceId>

@Immutable
public final class TraceId
extends Object
implements Comparable<TraceId>

A class that represents a trace identifier. A valid trace identifier is a 16-byte array with at least one non-zero byte.

Field Summary

Fields

Modifier and Type	Field and Description
static TraceId	INVALID The invalid TraceId.
static int	SIZE The size in bytes of the TraceId.

Method Summary

Modifier and Type	Method and Description
int	compareTo(TraceId that)
void	copyBytesTo(byte[] dest, int destOffset) Copies the byte array representations of the TraceId into the dest beginning at the destOffset offset.
boolean	equals(Object obj)
static TraceId	fromBytes(byte[] buffer) Returns a TraceId built from a byte representation.
static TraceId	fromBytes(byte[] src, int srcOffset) Returns a TraceId whose representation is copied from the src beginning at the srcOffset offset.
static TraceId	generateRandomId(Random random) Generates a new random TraceId.
byte[]	getBytes() Returns the 16-bytes array representation of the TraceId.
int	hashCode()
boolean	isValid() Returns whether the TraceId is valid.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

SIZE

public static final int SIZE

The size in bytes of the TraceId.

See Also:

Constant Field Values

INVALID

public static final TraceId INVALID

The invalid TraceId. All bytes are '\0'.

Method Detail

fromBytes

public static TraceId fromBytes(byte[] buffer)

Returns a TraceId built from a byte representation.

Equivalent with:

 TraceId.fromBytes(buffer, 0);
 

Parameters:

buffer - the representation of the TraceId.

Returns:

a TraceId whose representation is given by the buffer parameter.

Throws:

NullPointerException - if buffer is null.

IllegalArgumentException - if buffer.length is not SIZE.

fromBytes

public static TraceId fromBytes(byte[] src,
                                int srcOffset)

Returns a TraceId whose representation is copied from the src beginning at the srcOffset offset.

Parameters:

src - the buffer where the representation of the TraceId is copied.

srcOffset - the offset in the buffer where the representation of the TraceId begins.

Returns:

a TraceId whose representation is copied from the buffer.

Throws:

NullPointerException - if src is null.

IndexOutOfBoundsException - if srcOffset+TraceId.SIZE is greater than src.length.

generateRandomId

public static TraceId generateRandomId(Random random)

Generates a new random TraceId.

Parameters:

random - the random number generator.

Returns:

a new valid TraceId.

getBytes

public byte[] getBytes()

Returns the 16-bytes array representation of the TraceId.

Returns:

the 16-bytes array representation of the TraceId.

copyBytesTo

public void copyBytesTo(byte[] dest,
                        int destOffset)

Copies the byte array representations of the TraceId into the dest beginning at the destOffset offset.

Equivalent with (but faster because it avoids any new allocations):

 System.arraycopy(getBytes(), 0, dest, destOffset, TraceId.SIZE);
 

Parameters:

dest - the destination buffer.

destOffset - the starting offset in the destination buffer.

Throws:

NullPointerException - if dest is null.

IndexOutOfBoundsException - if destOffset+TraceId.SIZE is greater than dest.length.

isValid

public boolean isValid()

Returns whether the TraceId is valid. A valid trace identifier is a 16-byte array with at least one non-zero byte.

Returns:

true if the TraceId is valid.

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Overrides:

toString in class Object

compareTo

public int compareTo(TraceId that)

Specified by:

compareTo in interface Comparable<TraceId>