Tag (Apache HBase 2.4.0 API)

All Known Implementing Classes:

ArrayBackedTag, ByteBufferTag
```
@InterfaceAudience.LimitedPrivate(value="Coprocesssor")
 @InterfaceStability.Evolving
public interface Tag
```
Tags are part of cells and helps to add metadata about them. Metadata could be ACLs, visibility labels, etc.
Each Tag is having a type (one byte) and value part. The max value length for a Tag is 65533.
See TagType for reserved tag types.

Field Summary

Fields
Modifier and Type	Field and Description
`static byte`	`CUSTOM_TAG_TYPE_RANGE` Custom tags if created are suggested to be above this range.
`static int`	`INFRASTRUCTURE_SIZE`
`static int`	`MAX_TAG_LENGTH`
`static int`	`TAG_LENGTH_SIZE`
`static int`	`TYPE_LENGTH_SIZE`

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`static byte[]`	`cloneValue(Tag tag)` Returns tag value in a new byte array.
`static void`	`copyValueTo(Tag tag, byte[] out, int offset)` Copies the tag's value bytes to the given byte array
`byte`	`getType()`
`byte[]`	`getValueArray()`
`static byte`	`getValueAsByte(Tag tag)` Converts the value bytes of the given tag into a byte value
`static long`	`getValueAsLong(Tag tag)` Converts the value bytes of the given tag into a long value
`static String`	`getValueAsString(Tag tag)` Converts the value bytes of the given tag into a String value
`ByteBuffer`	`getValueByteBuffer()`
`int`	`getValueLength()`
`int`	`getValueOffset()`
`boolean`	`hasArray()` Tells whether or not this Tag is backed by a byte array.
`static boolean`	`matchingValue(Tag t1, Tag t2)` Matches the value part of given tags

- Field Detail
  - TYPE_LENGTH_SIZE
```
static final int TYPE_LENGTH_SIZE
```
    See Also:
    
    Constant Field Values
  - TAG_LENGTH_SIZE
```
static final int TAG_LENGTH_SIZE
```
    See Also:
    
    Constant Field Values
  - INFRASTRUCTURE_SIZE
```
static final int INFRASTRUCTURE_SIZE
```
    See Also:
    
    Constant Field Values
  - MAX_TAG_LENGTH
```
static final int MAX_TAG_LENGTH
```
    See Also:
    
    Constant Field Values
  - CUSTOM_TAG_TYPE_RANGE
```
static final byte CUSTOM_TAG_TYPE_RANGE
```
    Custom tags if created are suggested to be above this range. So that it does not overlap with internal tag types
    
    See Also:
    
    Constant Field Values
- Method Detail
  - getType
```
byte getType()
```
    Returns:
    
    the tag type
  - getValueOffset
```
int getValueOffset()
```
    Returns:
    
    Offset of tag value within the backed buffer
  - getValueLength
```
int getValueLength()
```
    Returns:
    
    Length of tag value within the backed buffer
  - hasArray
```
boolean hasArray()
```
    Tells whether or not this Tag is backed by a byte array.
    
    Returns:
    
    true when this Tag is backed by byte array
  - getValueArray
```
byte[] getValueArray()
```
    Returns:
    
    The array containing the value bytes.
    
    Throws:
    
    UnsupportedOperationException - when hasArray() return false. Use getValueByteBuffer() in such situation
  - getValueByteBuffer
```
ByteBuffer getValueByteBuffer()
```
    Returns:
    
    The ByteBuffer containing the value bytes.
  - cloneValue
```
static byte[] cloneValue(Tag tag)
```
    Returns tag value in a new byte array. Primarily for use client-side. If server-side, use getValueArray() with appropriate getValueOffset() and getValueLength() instead to save on allocations.
    
    Parameters:
    
    tag - The Tag whose value to be returned
    
    Returns:
    
    tag value in a new byte array.
  - getValueAsString
```
static String getValueAsString(Tag tag)
```
    Converts the value bytes of the given tag into a String value
    
    Parameters:
    
    tag - The Tag
    
    Returns:
    
    value as String
  - matchingValue
```
static boolean matchingValue(Tag t1,
                             Tag t2)
```
    Matches the value part of given tags
    
    Parameters:
    
    t1 - Tag to match the value
    
    t2 - Tag to match the value
    
    Returns:
    
    True if values of both tags are same.
  - copyValueTo
```
static void copyValueTo(Tag tag,
                        byte[] out,
                        int offset)
```
    Copies the tag's value bytes to the given byte array
    
    Parameters:
    
    tag - The Tag
    
    out - The byte array where to copy the Tag value.
    
    offset - The offset within 'out' array where to copy the Tag value.
  - getValueAsLong
```
static long getValueAsLong(Tag tag)
```
    Converts the value bytes of the given tag into a long value
    
    Parameters:
    
    tag - The Tag
    
    Returns:
    
    value as long
  - getValueAsByte
```
static byte getValueAsByte(Tag tag)
```
    Converts the value bytes of the given tag into a byte value
    
    Parameters:
    
    tag - The Tag
    
    Returns:
    
    value as byte

Interface Tag

Field Summary

Method Summary

Field Detail

TYPE_LENGTH_SIZE

TAG_LENGTH_SIZE

INFRASTRUCTURE_SIZE

MAX_TAG_LENGTH

CUSTOM_TAG_TYPE_RANGE

Method Detail

getType

getValueOffset

getValueLength

hasArray

getValueArray

getValueByteBuffer

cloneValue

getValueAsString

matchingValue

copyValueTo

getValueAsLong

getValueAsByte