Package org.apache.sshd.sftp.client

Interface SftpVersionSelector

All Known Implementing Classes:

SftpVersionSelector.NamedVersionSelector

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface SftpVersionSelector

Author:

Apache MINA SSHD Project

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	SftpVersionSelector.NamedVersionSelector	Wraps a SftpVersionSelector and assigns it a name.

Field Summary

Fields

Modifier and Type	Field	Description
static SftpVersionSelector.NamedVersionSelector	CURRENT	An SftpVersionSelector that returns the current version
static SftpVersionSelector.NamedVersionSelector	MAXIMUM	An SftpVersionSelector that returns the maximum available version
static SftpVersionSelector.NamedVersionSelector	MINIMUM	An SftpVersionSelector that returns the minimum available version

Method Summary

Modifier and Type	Method	Description
static SftpVersionSelector.NamedVersionSelector	fixedVersionSelector(int version)	Creates a selector the always returns the requested (fixed version) regardless of what the current or reported available versions are.
static SftpVersionSelector.NamedVersionSelector	preferredVersionSelector(int... preferred)	Selects a version in order of preference - if none of the preferred versions is listed as available then an exception is thrown when the selectVersion(ClientSession, boolean, int, List) method is invoked
static SftpVersionSelector.NamedVersionSelector	preferredVersionSelector(Iterable<? extends Number> preferred)	Selects a version in order of preference - if none of the preferred versions is listed as available then an exception is thrown when the selectVersion(ClientSession, boolean, int, List) method is invoked
static SftpVersionSelector.NamedVersionSelector	resolveVersionSelector(String selector)	Parses the input string to see if it matches one of the "known" selectors names (case insensitive).
int	selectVersion(ClientSession session, boolean initial, int current, List<Integer> available)

Field Detail

CURRENT

static final SftpVersionSelector.NamedVersionSelector CURRENT

An SftpVersionSelector that returns the current version

MAXIMUM

static final SftpVersionSelector.NamedVersionSelector MAXIMUM

An SftpVersionSelector that returns the maximum available version

MINIMUM

static final SftpVersionSelector.NamedVersionSelector MINIMUM

An SftpVersionSelector that returns the minimum available version

Method Detail

selectVersion

int selectVersion(ClientSession session,
                  boolean initial,
                  int current,
                  List<Integer> available)

Parameters:

session - The ClientSession through which the SFTP connection is made

initial - If true then this is the initial version sent via SSH_FXP_INIT otherwise it is a re-negotiation.

current - The current version negotiated with the server

available - Extra versions available - may be empty and/or contain only the current one

Returns:

The new requested version - if same as current, then nothing is done

fixedVersionSelector

static SftpVersionSelector.NamedVersionSelector fixedVersionSelector(int version)

Creates a selector the always returns the requested (fixed version) regardless of what the current or reported available versions are. If the requested version is not reported as available then an exception will be eventually thrown by the client during re-negotiation phase.

Parameters:

version - The requested version

Returns:

The SftpVersionSelector.NamedVersionSelector wrapping the requested version

preferredVersionSelector

static SftpVersionSelector.NamedVersionSelector preferredVersionSelector(int... preferred)

Selects a version in order of preference - if none of the preferred versions is listed as available then an exception is thrown when the selectVersion(ClientSession, boolean, int, List) method is invoked

Parameters:

preferred - The preferred versions in decreasing order of preference (i.e., most preferred is 1st) - may not be null/empty

Returns:

A SftpVersionSelector.NamedVersionSelector that attempts to select the most preferred version that is also listed as available.

preferredVersionSelector

static SftpVersionSelector.NamedVersionSelector preferredVersionSelector(Iterable<? extends Number> preferred)

Selects a version in order of preference - if none of the preferred versions is listed as available then an exception is thrown when the selectVersion(ClientSession, boolean, int, List) method is invoked

Parameters:

preferred - The preferred versions in decreasing order of preference (i.e., most preferred is 1st)

Returns:

A SftpVersionSelector.NamedVersionSelector that attempts to select the most preferred version that is also listed as available.

resolveVersionSelector

static SftpVersionSelector.NamedVersionSelector resolveVersionSelector(String selector)

Parses the input string to see if it matches one of the "known" selectors names (case insensitive). If not, then checks if it is a single number and uses it as a fixed version. Otherwise, assumes a comma separated list of versions in preferred order.

Parameters:

selector - The selector value - if null/empty then returns CURRENT

Returns:

Parsed SftpVersionSelector.NamedVersionSelector