TransportProtocol.java
/*
* Copyright (C) 2011, Google Inc. and others
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Distribution License v. 1.0 which is available at
* https://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
package org.eclipse.jgit.transport;
import java.util.Collections;
import java.util.EnumSet;
import java.util.Set;
import org.eclipse.jgit.errors.NotSupportedException;
import org.eclipse.jgit.errors.TransportException;
import org.eclipse.jgit.internal.JGitText;
import org.eclipse.jgit.lib.Repository;
/**
* Describes a way to connect to another Git repository.
* <p>
* Implementations of this class are typically immutable singletons held by
* static class members, for example:
*
* <pre>
* package com.example.my_transport;
*
* class MyTransport extends Transport {
* public static final TransportProtocol PROTO = new TransportProtocol() {
* public String getName() {
* return "My Protocol";
* }
* };
* }
* </pre>
*
* <p>
* Applications may register additional protocols for use by JGit by calling
* {@link org.eclipse.jgit.transport.Transport#register(TransportProtocol)}.
* Because that API holds onto the protocol object by a WeakReference,
* applications must ensure their own ClassLoader retains the TransportProtocol
* for the life of the application. Using a static singleton pattern as above
* will ensure the protocol is valid so long as the ClassLoader that defines it
* remains valid.
* <p>
* Applications may automatically register additional protocols by filling in
* the names of their TransportProtocol defining classes using the services file
* {@code META-INF/services/org.eclipse.jgit.transport.Transport}. For each
* class name listed in the services file, any static fields of type
* {@code TransportProtocol} will be automatically registered. For the above
* example the string {@code com.example.my_transport.MyTransport} should be
* listed in the file, as that is the name of the class that defines the static
* PROTO singleton.
*/
public abstract class TransportProtocol {
/** Fields within a {@link URIish} that a transport uses. */
public enum URIishField {
/** the user field */
USER,
/** the pass (aka password) field */
PASS,
/** the host field */
HOST,
/** the port field */
PORT,
/** the path field */
PATH,
}
/**
* Get text name of the protocol suitable for display to a user.
*
* @return text name of the protocol suitable for display to a user.
*/
public abstract String getName();
/**
* Get immutable set of schemes supported by this protocol.
*
* @return immutable set of schemes supported by this protocol.
*/
public Set<String> getSchemes() {
return Collections.emptySet();
}
/**
* Get immutable set of URIishFields that must be filled in.
*
* @return immutable set of URIishFields that must be filled in.
*/
public Set<URIishField> getRequiredFields() {
return Collections.unmodifiableSet(EnumSet.of(URIishField.PATH));
}
/**
* Get immutable set of URIishFields that may be filled in.
*
* @return immutable set of URIishFields that may be filled in.
*/
public Set<URIishField> getOptionalFields() {
return Collections.emptySet();
}
/**
* Get the default port if the protocol supports a port, else -1.
*
* @return the default port if the protocol supports a port, else -1.
*/
public int getDefaultPort() {
return -1;
}
/**
* Determine if this protocol can handle a particular URI.
* <p>
* Implementations should try to avoid looking at the local filesystem, but
* may look at implementation specific configuration options in the remote
* block of {@code local.getConfig()} using {@code remoteName} if the name
* is non-null.
* <p>
* The default implementation of this method matches the scheme against
* {@link #getSchemes()}, required fields against
* {@link #getRequiredFields()}, and optional fields against
* {@link #getOptionalFields()}, returning true only if all of the fields
* match the specification.
*
* @param uri
* address of the Git repository; never null.
* @return true if this protocol can handle this URI; false otherwise.
*/
public boolean canHandle(URIish uri) {
return canHandle(uri, null, null);
}
/**
* Determine if this protocol can handle a particular URI.
* <p>
* Implementations should try to avoid looking at the local filesystem, but
* may look at implementation specific configuration options in the remote
* block of {@code local.getConfig()} using {@code remoteName} if the name
* is non-null.
* <p>
* The default implementation of this method matches the scheme against
* {@link #getSchemes()}, required fields against
* {@link #getRequiredFields()}, and optional fields against
* {@link #getOptionalFields()}, returning true only if all of the fields
* match the specification.
*
* @param uri
* address of the Git repository; never null.
* @param local
* the local repository that will communicate with the other Git
* repository. May be null if the caller is only asking about a
* specific URI and does not have a local Repository.
* @param remoteName
* name of the remote, if the remote as configured in
* {@code local}; otherwise null.
* @return true if this protocol can handle this URI; false otherwise.
*/
public boolean canHandle(URIish uri, Repository local, String remoteName) {
if (!getSchemes().isEmpty() && !getSchemes().contains(uri.getScheme()))
return false;
for (URIishField field : getRequiredFields()) {
switch (field) {
case USER:
if (uri.getUser() == null || uri.getUser().length() == 0)
return false;
break;
case PASS:
if (uri.getPass() == null || uri.getPass().length() == 0)
return false;
break;
case HOST:
if (uri.getHost() == null || uri.getHost().length() == 0)
return false;
break;
case PORT:
if (uri.getPort() <= 0)
return false;
break;
case PATH:
if (uri.getPath() == null || uri.getPath().length() == 0)
return false;
break;
default:
return false;
}
}
Set<URIishField> canHave = EnumSet.copyOf(getRequiredFields());
canHave.addAll(getOptionalFields());
if (uri.getUser() != null && !canHave.contains(URIishField.USER))
return false;
if (uri.getPass() != null && !canHave.contains(URIishField.PASS))
return false;
if (uri.getHost() != null && !canHave.contains(URIishField.HOST))
return false;
if (uri.getPort() > 0 && !canHave.contains(URIishField.PORT))
return false;
if (uri.getPath() != null && !canHave.contains(URIishField.PATH))
return false;
return true;
}
/**
* Open a Transport instance to the other repository.
* <p>
* Implementations should avoid making remote connections until an operation
* on the returned Transport is invoked, however they may fail fast here if
* they know a connection is impossible, such as when using the local
* filesystem and the target path does not exist.
* <p>
* Implementations may access implementation-specific configuration options
* within {@code local.getConfig()} using the remote block named by the
* {@code remoteName}, if the name is non-null.
*
* @param uri
* address of the Git repository.
* @param local
* the local repository that will communicate with the other Git
* repository.
* @param remoteName
* name of the remote, if the remote as configured in
* {@code local}; otherwise null.
* @return the transport.
* @throws org.eclipse.jgit.errors.NotSupportedException
* this protocol does not support the URI.
* @throws org.eclipse.jgit.errors.TransportException
* the transport cannot open this URI.
*/
public abstract Transport open(URIish uri, Repository local,
String remoteName)
throws NotSupportedException, TransportException;
/**
* Open a new transport instance to the remote repository. Use default
* configuration instead of reading from configuration files.
*
* @param uri
* a {@link org.eclipse.jgit.transport.URIish} object.
* @return new Transport
* @throws org.eclipse.jgit.errors.NotSupportedException
* @throws org.eclipse.jgit.errors.TransportException
*/
public Transport open(URIish uri)
throws NotSupportedException, TransportException {
throw new NotSupportedException(JGitText
.get().transportNeedsRepository);
}
}