Interest Class

The Interest class represents an NDN Interest packet.

[C++]:

#include <ndn-cpp/interest.hpp>

Namespace: ndn

[Python]:Module: pyndn [Java]:Package: net.named_data.jndn

Note

You don’t have to set the interest nonce. A nonce is automatically generated when the interest is wire encoded.

Interest Constructors

Interest Constructor (optional Name)

Create a new Interest with the optional name, and where other values are unspecified.

[C++]:

Interest(
    [const Name& name]
);

[Python]:

def __init__(self
    [, name  # Name]
)

[JavaScript]:

var Interest = function Interest (
    [name  // Name]
)

[Java]:

public Interest(
    [Name name]
)

Parameters:

• name

  (optional) The name for the interest which is copied. If omitted, use a blank name.

Interest Constructor (from URI)

Create a new Interest with a Name from the given URI string, and where other values are unspecified.

[C++]:

Interest(
    const char* uri
);

[Python]:

def __init__(self,
    uri  # str
)

[JavaScript]:

var Interest = function Interest(
    uri  // string
)

[Java]:

public Interest(
    String uri
)

Parameters:

• uri

  The URI in the NDN URI Scheme.

Interest Constructor (copy)

Create a new Interest as a deep copy of the given interest.

[C++]:

Interest(
    const Interest& interest
);

[Python]:

def __init__(self,
    interest  # Interest
)

[JavaScript]:

var Interest = function Interest(
    interest  // Interest
)

[Java]:

public Interest(
    Interest interest
)

Parameters:

• interest

  The Interest to copy.

Interest Get Methods

Interest.getCanBePrefix Method

Get the CanBePrefix flag. If not specified, the default is true, or the value from setDefaultCanBePrefix.

[C++]:

bool getCanBePrefix() const;

[Python]:

# Returns bool
def getCanBePrefix(self)

[JavaScript]:

// Returns boolean
Interest.prototype.getCanBePrefix = function()

[Java]:

public final boolean getCanBePrefix()

Returns:

The CanBePrefix flag.

Interest.getChildSelector Method

Get the child selector.

[C++]:

int getChildSelector() const;

[Python]:

# Returns int
def getChildSelector(self)

[JavaScript]:

// Returns number
Interest.prototype.getChildSelector = function()

[Java]:

public final int getChildSelector()

Returns:

The child selector. If not specified, return -1 (C++ and Java) or None (Python) or undefined (JavaScript).

Interest.getDefaultCanBePrefix Method

Get the default value of the CanBePrefix flag used in the Interest constructor. You can change this with setDefaultCanBePrefix.

[C++]:

static bool getDefaultCanBePrefix();

[Python]:

# Returns bool
@staticmethod
def getDefaultCanBePrefix()

[JavaScript]:

// Returns boolean
Interest.getDefaultCanBePrefix = function()

[Java]:

public static boolean getDefaultCanBePrefix()

Returns:

The default value of the CanBePrefix flag.

Interest.getExclude Method

Get the interest Exclude object.

[C++]:

Exclude& getExclude();

const Exclude& getExclude() const;

[Python]:

# Returns Exclude
def getExclude(self)

[JavaScript]:

// Returns Exclude
Interest.prototype.getExclude = function()

[Java]:

public final Exclude getExclude()

Returns:

The Exclude object. If not specified, the exclude size() is 0.

Interest.getForwardingHint Method

Get the forwarding hint object which you can modify to add or remove forwarding hints.

[C++]:

DelegationSet& getForwardingHint();

const DelegationSet& getForwardingHint() const;

[Python]:

# Returns DelegationSet
def getForwardingHint(self)

[JavaScript]:

// Returns DelegationSet
Interest.prototype.getForwardingHint = function()

[Java]:

public final DelegationSet getForwardingHint()

Returns:

The forwarding hint as a DelegationSet

Interest.getIncomingFaceId Method

Get the incoming face ID according to the incoming packet header (if the forwarder is configured to include it in the header).

[C++]:

uint64_t getIncomingFaceId() const;

[Python]:

# Returns int
def getIncomingFaceId(self)

[JavaScript]:

// Returns number
Interest.prototype.getIncomingFaceId = function()

[Java]:

public final long getIncomingFaceId()

Returns:

The incoming face ID. If not specified, return (uint64_t)-1 (C++) or None (Python) or undefined (JavaScript) or -1 (Java).

Interest.getInterestLifetimeMilliseconds Method

Get the interest lifetime.

[C++]:

Milliseconds getInterestLifetimeMilliseconds() const;

[Python]:

# Returns float
def getInterestLifetimeMilliseconds(self)

[JavaScript]:

// Returns number
Interest.prototype.getInterestLifetimeMilliseconds = function()

[Java]:

public final double getInterestLifetimeMilliseconds()

Returns:

The interest lifetime in milliseconds. If not specified, return -1 (C++ and Java) or None (Python) or undefined (JavaScript).

Interest.getKeyLocator Method

Get the interest KeyLocator object.

[C++]:

KeyLocator& getKeyLocator();

const KeyLocator& getKeyLocator() const;

[Python]:

# Returns KeyLocator
def getKeyLocator(self)

[JavaScript]:

// Returns KeyLocator
Interest.prototype.getKeyLocator = function()

[Java]:

public final KeyLocator getKeyLocator()

Returns:

The KeyLocator object. If not specified, the key locator getType() is not specified.

Interest.getMaxSuffixComponents Method

Get the max suffix components count.

Note

The suffix components count includes the implicit digest component of the full name in the data packet. For example, if the interest name is the prefix /a/b and the data packet name is /a/b/c, then the data packet name has 2 suffix components: “c” and the implicit digest which is not shown.

[C++]:

int getMaxSuffixComponents() const;

[Python]:

# Returns int
def getMaxSuffixComponents(self)

[JavaScript]:

// Returns number
Interest.prototype.getMaxSuffixComponents = function()

[Java]:

public final int getMaxSuffixComponents()

Returns:

The max suffix components count. If not specified, return -1 (C++ and Java) or None (Python) or undefined (JavaScript).

Interest.getMinSuffixComponents Method

Get the min suffix components count.

Note

The suffix components count includes the implicit digest component of the full name in the data packet. For example, if the interest name is the prefix /a/b and the data packet name is /a/b/c, then the data packet name has 2 suffix components: “c” and the implicit digest which is not shown.

[C++]:

int getMinSuffixComponents() const;

[Python]:

# Returns int
def getMinSuffixComponents(self)

[JavaScript]:

// Returns number
Interest.prototype.getMinSuffixComponents = function()

[Java]:

public final int getMinSuffixComponents()

Returns:

The min suffix components count. If not specified, return -1 (C++ and Java) or None (Python) or undefined (JavaScript).

Interest.getMustBeFresh Method

Get the MustBeFresh flag.

[C++]:

bool getMustBeFresh() const;

[Python]:

# Returns bool
def getMustBeFresh(self)

[JavaScript]:

// Returns boolean
Interest.prototype.getMustBeFresh = function()

[Java]:

public final boolean getMustBeFresh()

Returns:

True if must be fresh, otherwise false. If not specified, the default is false.

Interest.getName Method

Get the interest name.

[C++]:

Name& getName();

const Name& getName() const;

[Python]:

# Returns Name
def getName(self)

[JavaScript]:

// Returns Name
Interest.prototype.getName = function()

[Java]:

public final Name getName()

Returns:

The name. If not specified, the name size() is 0.

Interest.getNonce Method

Get the nonce value from the incoming interest. If you change any of the fields in this Interest object, then the nonce value is cleared.

Note

When you create an interest, you don’t have to set the nonce. A nonce is automatically generated when the interest is wire encoded.

[C++]:

const Blob& getNonce() const;

[Python]:

# Returns Blob
def getNonce(self)

[JavaScript]:

// Returns Blob
Interest.prototype.getNonce = function()

[Java]:

public final Blob getNonce()

Returns:

The nonce. If not specified, the value isNull().

Interest.getParameters Method

Get the Interest parameters.

[C++]:

const Blob& getParameters() const;

[Python]:

# Returns Blob
def getParameters(self)

[JavaScript]:

// Returns Blob
Interest.prototype.getParameters = function()

[Java]:

public final Blob getParameters()

Returns:

The parameters as a Blob, which isNull() if unspecified.

Interest Set Methods

Interest.setCanBePrefix Method

Set the CanBePrefix flag.

[C++]:

Interest& setCanBePrefix(
    bool canBePrefix
);

[Python]:

# Returns Interest
def setCanBePrefix(self,
    canBePrefix  # bool
)

[JavaScript]:

// Returns Interest
Interest.prototype.setCanBePrefix = function(
    canBePrefix  // boolean
)

[Java]:

public final Interest setCanBePrefix(
    boolean canBePrefix
)

Parameters:

• canBePrefix

  True if the Interest name can be a prefix. If you do not set this flag, the default value is true.

Returns:

This Interest so that you can chain calls to update values.

Interest.setChildSelector Method

Set the child selector.

[C++]:

Interest& setChildSelector(
    int childSelector
);

[Python]:

# Returns Interest
def setChildSelector(self,
    childSelector  # int
)

[JavaScript]:

// Returns Interest
Interest.prototype.setChildSelector = function(
    childSelector  // number
)

[Java]:

public final Interest setChildSelector(
    int childSelector
)

Parameters:

• childSelector

  The child selector. If not specified, set to -1 (C++ and Java) or None (Python) or undefined (JavaScript).

Returns:

This Interest so that you can chain calls to update values.

Interest.setDefaultCanBePrefix Method

Set the default value of the CanBePrefix flag used in the Interest constructor. The default is currently true, but will be changed at a later date. The application should call this before creating any Interest (even to set the default again to true), or the application should explicitly call setCanBePrefix after creating the Interest. Otherwise wireEncode will print a warning message. This is to avoid breaking any code when the library default for CanBePrefix is changed at a later date.

[C++]:

static void setDefaultCanBePrefix(
    bool defaultCanBePrefix
);

[Python]:

@staticmethod
def setDefaultCanBePrefix(
    defaultCanBePrefix  # bool
)

[JavaScript]:

Interest.setDefaultCanBePrefix = function(
    defaultCanBePrefix  // boolean
)

[Java]:

public static void setDefaultCanBePrefix(
    boolean defaultCanBePrefix
)

Parameters:

• defaultCanBePrefix

  The default value of the CanBePrefix flag.

Interest.setExclude Method

Set this interest to use a copy of the given Exclude object.

Note

You can also call getExclude and change the exclude entries directly.

[C++]:

Interest& setExclude(
    const Exclude& exclude
);

[Python]:

# Returns Interest
def setExclude(self,
    exclude  # Exclude
)

[JavaScript]:

// Returns Interest
Interest.prototype.setExclude = function(
    exclude  // Exclude
)

[Java]:

public final Interest setExclude(
    Exclude exclude
)

Parameters:

• exclude

  The Exclude object. This makes a copy of the object. If no exclude is specified, set to a new default Exclude(), or to an Exclude with size() 0.

Returns:

This Interest so that you can chain calls to update values.

Interest.setForwardingHint Method

Set this interest to use a copy of the given DelegationSet object as the forwarding hint.

Note

You can also call getForwardingHint and change the forwarding hint directly.

[C++]:

Interest& setForwardingHint(
    const DelegationSet& forwardingHint
);

[Python]:

# Returns Interest
def setForwardingHint(self,
    forwardingHint  # DelegationSet
)

[JavaScript]:

// Returns Interest
Interest.prototype.setForwardingHint = function(
    forwardingHint  // DelegationSet
)

[Java]:

public final Interest setForwardingHint(
    DelegationSet forwardingHint
)

Parameters:

• forwardingHint

  The DelegationSet object. to use as the forwarding hint. This makes a copy of the object. If no forwarding hint is specified, set to a new default DelegationSet() with no entries.

Returns:

This Interest so that you can chain calls to update values.

Interest.setInterestLifetimeMilliseconds Method

Set the interest lifetime.

[C++]:

Interest& setInterestLifetimeMilliseconds(
    Milliseconds interestLifetimeMilliseconds
);

[Python]:

# Returns Interest
def setInterestLifetimeMilliseconds(self,
    interestLifetimeMilliseconds  # float
)

[JavaScript]:

// Returns Interest
Interest.prototype.setInterestLifetimeMilliseconds = function(
    interestLifetimeMilliseconds  // number
)

[Java]:

public final Interest setInterestLifetimeMilliseconds(
    double interestLifetimeMilliseconds
)

Parameters:

• interestLifetimeMilliseconds

  The interest lifetime in milliseconds. If not specified, set to -1 (C++ and Java) or None (Python) or undefined (JavaScript).

Returns:

This Interest so that you can chain calls to update values.

Interest.setKeyLocator Method

Set this interest to use a copy of the given KeyLocator object.

Note

You can also call getKeyLocator and change the key locator directly.

[C++]:

Interest& setKeyLocator(
    const KeyLocator& keyLocator
);

[Python]:

# Returns Interest
def setKeyLocator(self,
    keyLocator  # KeyLocator
)

[JavaScript]:

// Returns Interest
Interest.prototype.setKeyLocator = function(
    keyLocator  // KeyLocator
)

[Java]:

public final Interest setKeyLocator(
    KeyLocator keyLocator
)

Parameters:

• keyLocator

  The KeyLocator object. This makes a copy of the object. If no key locator is specified, set to a new default KeyLocator(), or to a KeyLocator with an unspecified type.

Returns:

This Interest so that you can chain calls to update values.

Interest.setMustBeFresh Method

Set the MustBeFresh flag.

[C++]:

Interest& setMustBeFresh(
    bool mustBeFresh
);

[Python]:

# Returns Interest
def setMustBeFresh(self,
    mustBeFresh  # bool
)

[JavaScript]:

// Returns Interest
Interest.prototype.setMustBeFresh = function(
    mustBeFresh  // boolean
)

[Java]:

public final Interest setMustBeFresh(
    boolean mustBeFresh
)

Parameters:

• mustBeFresh

  True if the content must be fresh, otherwise false. If you do not set this flag, the default value is false.

Returns:

This Interest so that you can chain calls to update values.

Interest.setMaxSuffixComponents Method

Set the max suffix components count.

Note

The suffix components count includes the implicit digest component of the full name in the data packet. For example, if the interest name is the prefix /a/b and the data packet name is /a/b/c, then the data packet name has 2 suffix components: “c” and the implicit digest which is not shown.

[C++]:

Interest& setMaxSuffixComponents(
    int maxSuffixComponents
);

[Python]:

# Returns Interest
def setMaxSuffixComponents(self,
    maxSuffixComponents  # int
)

[JavaScript]:

// Returns Interest
Interest.prototype.setMaxSuffixComponents = function(
    maxSuffixComponents  // number
)

[Java]:

public final Interest setMaxSuffixComponents(
    int maxSuffixComponents
)

Parameters:

• maxSuffixComponents

  The max suffix components count. If not specified, set to -1 (C++ and Java) or None (Python) or undefined (JavaScript).

Returns:

This Interest so that you can chain calls to update values.

Interest.setMinSuffixComponents Method

Set the min suffix components count.

Note

The suffix components count includes the implicit digest component of the full name in the data packet. For example, if the interest name is the prefix /a/b and the data packet name is /a/b/c, then the data packet name has 2 suffix components: “c” and the implicit digest which is not shown.

[C++]:

Interest& setMinSuffixComponents(
    int minSuffixComponents
);

[Python]:

# Returns Interest
def setMinSuffixComponents(self,
    minSuffixComponents  # int
)

[JavaScript]:

// Returns Interest
Interest.prototype.setMinSuffixComponents = function(
    minSuffixComponents  // number
)

[Java]:

public final Interest setMinSuffixComponents(
    int minSuffixComponents
)

Parameters:

• minSuffixComponents

  The min suffix components count. If not specified, set to -1 (C++ and Java) or None (Python) or undefined (JavaScript).

Returns:

This Interest so that you can chain calls to update values.

Interest.setName Method

Set the interest name.

Note

You can also call getName and change the name values directly.

[C++]:

Interest& setName(
    const Name& name
);

[Python]:

# Returns Interest
def setName(self,
    name  # Name
)

[JavaScript]:

// Returns Interest
Interest.prototype.setName = function(
    name  // Name
)

[Java]:

public final Interest setName(
    Name name
)

Parameters:

• name

  The interest name. This makes a copy of the name.

Returns:

This Interest so that you can chain calls to update values.

Interest.setParameters Method

Set the Interest parameters to the given value.

[C++]:

Interest& setParameters(
    const Blob& parameters
);

[Python]:

# Returns Interest
def setParameters(self,
    parameters  # Blob
)

[JavaScript]:

// Returns Interest
Interest.prototype.setParameters = function(
    parameters  // Blob
)

[Java]:

public final Interest setParameters(
    Blob parameters
)

Parameters:

• parameters

  The Interest parameters Blob.

Returns:

This Interest so that you can chain calls to update values.

Interest.appendParametersDigestToName Method

Append the digest of the Interest parameters to the Name as a ParametersSha256DigestComponent. However, if the Interest parameters is unspecified, do nothing. This does not check if the Name already has a parameters digest component, so calling again will append another component.

[C++]:

Interest& appendParametersDigestToName();

[Python]:

# Returns Interest
def appendParametersDigestToName(self)

[JavaScript]:

// Returns Interest
Interest.prototype.appendParametersDigestToName = function()

[Java]:

public final Interest appendParametersDigestToName()

Returns:

This Interest so that you can chain calls to update values.

Interest.matchesData Method

Check if the given Data packet can satisfy this Interest. This method considers the Name, MinSuffixComponents, MaxSuffixComponents, PublisherPublicKeyLocator, and Exclude. It does not consider the ChildSelector or MustBeFresh.

[C++]:

bool matchesData(
    const Data& data
) const;

[Python]:

# Returns True or False
def matchesData(self,
    data  # Data
)

[JavaScript]:

// Returns boolean
Interest.prototype.matchesData = function(
    data  // Data
)

[Java]:

public final boolean matchesData(
    Data data
)

Parameters:

• data

  The Data packet to check.

Returns:

True if the given Data packet can satisfy this Interest.

Interest.matchesName Method

Return true if the components of this Interest’s name are the same as the leading components of the given name, and the name conforms to the interest selectors.

[C++]:

bool matchesName(
    const Name& name
) const;

[Python]:

# Returns True or False
def matchesName(self,
    name  # Name
)

[JavaScript]:

// Returns boolean
Interest.prototype.matchesName = function(
    name  // Name
)

[Java]:

public final boolean matchesName(
    Name name
)

Parameters:

• name

  The Name to check against this Interest.

Returns:

True if this interest’s name and interest selectors match the name.

Interest.refreshNonce Method

Update the bytes of the nonce with new random values. This ensures that the new nonce value is different than the current one. If the current nonce is not specified, this does nothing.

[C++]:

void refreshNonce();

[Python]:

def refreshNonce(self)

[JavaScript]:

Interest.prototype.refreshNonce = function()

[Java]:

public final void refreshNonce()

Interest.toUri Method

Experimental

This method is experimental. The NDN specifications don’t officially define how to add interest selectors to a URI.

Encode the name according to the “NDN URI Scheme”. If there are interest selectors, append “?” and add the selectors as a query string. For example “/test/name?ndn.ChildSelector=1”.

[C++]:

std::string toUri() const;

[Python]:

# Returns str
def toUri(self)

[JavaScript]:

// Returns string
Interest.prototype.toUri = function()

[Java]:

public final String toUri()

Returns:

The URI string.

Interest.wireDecode Methods

Interest.wireDecode Method (from Blob)

Decode the input from wire format and update this Interest. Also keep a pointer to the immutable input Blob for later use.

[C++]:

void wireDecode(
    const Blob& input
);

[Python]:

def wireDecode(self,
    input  # Blob
)

[JavaScript]:

Interest.prototype.wireDecode = function(
    input  // Blob
)

[Java]:

public final void wireDecode(
    Blob content
)

Parameters:

• input

  The immutable input byte array to be decoded.

Interest.wireDecode Method (copy from byte array)

Decode the input from wire format and update this Interest.

[C++]:

void wireDecode(
    const std::vector<uint8_t>& input
);

void wireDecode(
    const uint8_t *input,
    size_t inputLength
);

[Python]:

def wireDecode(self,
    input  # an array type with int elements
)

[JavaScript]:

Interest.prototype.wireDecode = function(
    input  // Buffer
)

[Java]:

public final void wireDecode(
    ByteBuffer input
)

Parameters:

• input

  The input byte array to be decoded.

Interest.wireEncode Method

Encode this Interest to a wire format.

[C++]:

SignedBlob wireEncode() const;

[Python]:

# Returns SignedBlob
def wireEncode()

[JavaScript]:

// Returns SignedBlob
Interest.prototype.wireEncode = function()

[Java]:

public final SignedBlob wireEncode()

Returns:

The encoded byte array as a SignedBlob.