Blob (jndn 0.14 API)

java.lang.Object
- net.named_data.jndn.util.Blob

All Implemented Interfaces:

Comparable

Direct Known Subclasses:

SignedBlob
```
public class Blob
extends Object
implements Comparable
```
A Blob holds a pointer to an immutable ByteBuffer. We use an immutable buffer so that it is OK to pass the object into methods because the new or old owner can’t change the bytes. Note that the pointer to the ByteBuffer can be null.

Constructor Summary

Constructors
Constructor and Description
`Blob()` Create a new Blob with a null pointer.
`Blob(Blob blob)` Create a new Blob and take another pointer to the given blob's buffer.
`Blob(byte[] value)` Create a new Blob with a copy of the bytes in the array.
`Blob(byte[] value, boolean copy)` Create a new Blob from the the byte array.
`Blob(ByteBuffer buffer, boolean copy)` Create a new Blob from an existing ByteBuffer.
`Blob(int[] value)` Create a new Blob with a copy of the bytes in the array.
`Blob(String value)` Create a new Blob from the UTF-8 encoding of the Unicode string.

Method Summary

Methods
Modifier and Type	Method and Description
`ByteBuffer`	`buf()` Get the read-only ByteBuffer.
`int`	`compare(Blob other)` Compare this to the other Blob using byte-by-byte comparison from their position to their limit.
`int`	`compareTo(Object o)`
`int`	`CompareTo(Object o)`
`boolean`	`equals(Blob other)`
`boolean`	`equals(Object other)`
`byte[]`	`getImmutableArray()` Get a byte array by calling ByteBuffer.array() if possible (because the ByteBuffer slice covers the entire backing array).
`int`	`hashCode()` If the hash code is already computed then return it, otherwise compute and return the hash code.
`boolean`	`isNull()` Check if the buffer pointer is null.
`int`	`size()` Get the size of the buffer.
`String`	`toHex()` Return a hex string of buf() from position to limit.
`static String`	`toHex(ByteBuffer buffer)` Return a hex string of the contents of buffer from position to limit.
`static void`	`toHex(ByteBuffer buffer, StringBuffer output)` Write a hex string of the contents of buffer from position to limit to the output.
`String`	`toString()` Decode the byte array as UTF8 and return the Unicode string.

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

- Constructor Detail
  - Blob
```
public Blob()
```
    Create a new Blob with a null pointer.
  - Blob
```
public Blob(Blob blob)
```
    Create a new Blob and take another pointer to the given blob's buffer.
    
    Parameters:
    blob - The Blob from which we take another pointer to the same buffer.
  - Blob
```
public Blob(ByteBuffer buffer,
    boolean copy)
```
    Create a new Blob from an existing ByteBuffer. IMPORTANT: If copy is false, after calling this constructor, if you keep a pointer to the buffer then you must treat it as immutable and promise not to change it.
    
    Parameters:
    buffer - The existing ByteBuffer. It is important that the buffer position and limit are correct.
    copy - If true, copy the contents into a new byte array. If false, just take a slice which uses the existing byte array in buffer.
  - Blob
```
public Blob(byte[] value,
    boolean copy)
```
    Create a new Blob from the the byte array. IMPORTANT: If copy is false, after calling this constructor, if you keep a pointer to the buffer then you must treat it as immutable and promise not to change it.
    
    Parameters:
    value - The byte array. If copy is true, this makes a copy.
    copy - If true, copy the contents into a new byte array. If false, just use ByteBuffer.wrap which uses the existing byte array.
  - Blob
```
public Blob(byte[] value)
```
    Create a new Blob with a copy of the bytes in the array.
    
    Parameters:
    value - The byte array to copy.
  - Blob
```
public Blob(int[] value)
```
    Create a new Blob with a copy of the bytes in the array.
    
    Parameters:
    value - The array of integer to copy where each integer is in the range 0 to 255.
  - Blob
```
public Blob(String value)
```
    Create a new Blob from the UTF-8 encoding of the Unicode string.
    
    Parameters:
    value - The Unicode string which is encoded as UTF-8.
- Method Detail
  - buf
```
public final ByteBuffer buf()
```
    Get the read-only ByteBuffer.
    
    Returns:
    The read-only ByteBuffer using asReadOnlyBuffer(), or null if the pointer is null.
  - getImmutableArray
```
public final byte[] getImmutableArray()
```
    Get a byte array by calling ByteBuffer.array() if possible (because the ByteBuffer slice covers the entire backing array). Otherwise return byte array as a copy of the ByteBuffer. This is called immutableArray to remind you not to change the contents of the returned array. This method is necessary because the read-only ByteBuffer returned by buf() doesn't allow you to call array().
    
    Returns:
    A byte array which you should not modify, or null if the pointer is null.
  - size
```
public final int size()
```
    Get the size of the buffer.
    
    Returns:
    The length (remaining) of the ByteBuffer, or 0 if the pointer is null.
  - isNull
```
public final boolean isNull()
```
    Check if the buffer pointer is null.
    
    Returns:
    True if the buffer pointer is null, otherwise false.
  - toHex
```
public final String toHex()
```
    Return a hex string of buf() from position to limit.
    
    Returns:
    A string of hex bytes, or "" if the buffer is null.
  - toHex
```
public static void toHex(ByteBuffer buffer,
         StringBuffer output)
```
    Write a hex string of the contents of buffer from position to limit to the output.
    
    Parameters:
    buffer - The buffer.
    output - The StringBuffer to write to.
  - toHex
```
public static String toHex(ByteBuffer buffer)
```
    Return a hex string of the contents of buffer from position to limit.
    
    Parameters:
    buffer - The buffer.
    
    Returns:
    A string of hex bytes.
  - equals
```
public final boolean equals(Blob other)
```
  - equals
```
public boolean equals(Object other)
```
    Overrides:
    
    equals in class Object
  - compare
```
public final int compare(Blob other)
```
    Compare this to the other Blob using byte-by-byte comparison from their position to their limit. If this and other are both isNull(), then this returns 0. If this isNull() and the other is not, return -1. If this is not isNull() and the other is, return 1. We compare explicitly because a Blob uses a ByteBuffer which compares based on signed byte, not unsigned byte.
    
    Parameters:
    other - The other Blob to compare with.
    
    Returns:
    0 If they compare equal, -1 if self is less than other, or 1 if self is greater than other. If both are equal up to the shortest, then return -1 if self is shorter than other, or 1 of self is longer than other.
  - compareTo
```
public final int compareTo(Object o)
```
    Specified by:
    
    compareTo in interface Comparable
  - CompareTo
```
public final int CompareTo(Object o)
```
  - hashCode
```
public int hashCode()
```
    If the hash code is already computed then return it, otherwise compute and return the hash code.
    
    Overrides:
    
    hashCode in class Object
    
    Returns:
    The hash code for the buffer, or 0 if the buffer is null.
  - toString
```
public String toString()
```
    Decode the byte array as UTF8 and return the Unicode string.
    
    Overrides:
    
    toString in class Object
    
    Returns:
    A unicode string, or "" if the buffer is null.

Class Blob

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

Blob

Blob

Blob

Blob

Blob

Blob

Blob

Method Detail

buf

getImmutableArray

size

isNull

toHex

toHex

toHex

equals

equals

compare

compareTo

CompareTo

hashCode

toString