Unified VCS API for different version control systems.

VCService.java

package crossover;

import java.io.Serializable;
import java.util.Collection;
import java.util.Date;
import java.util.List;
import java.util.concurrent.Future;

/**
 * Created by Noor on 3/26/17.
 */


/**
 *  Unified VCS API
 */

public interface VCService<R extends Serializable> {

    public Future<Void> checkout(String location, String url, String username, String password);

    public Collection<CommitLogEntry<R>> logs(String repo, int pageSize);

    public Collection<CommitLogEntry<R>> logs(String repo, R fromRevision, int pageSize);

    public Collection<CommitLogEntry<R>> logs(String repo, R fromRevision, R toRevision, int pageSize);

    public Collection<CommitLogEntry<R>> logs(String repo, R fromRevision, String branch, int pageSize);

    public Collection<CommitLogEntry<R>> logs(String repo, R fromRevision, R toRevision, String branch, int pageSize);

    public CommitLogEntry show(String repo, R revision);

    public List<DiffEntry> diffs(String repo,R fromRevision, R toRevision);

    public DiffEntry diff(String repo,R fromRevision, R toRevision,String file);

    public Future<byte[]> download(String repo, String filePath,R revision);

}

/**
 *  GIT Implementation draft
 */


class GitVCService implements VCService<String> {

    @Override
    public Future<Void> checkout(String location, String url, String username, String password) {

        return null;
    }

    @Override
    public Collection<CommitLogEntry<String>> logs(String repo, int pageSize) {
        return null;
    }

    @Override
    public Collection<CommitLogEntry<String>> logs(String repo, String fromRevision, int pageSize) {
        return null;
    }

    @Override
    public Collection<CommitLogEntry<String>> logs(String repo, String fromRevision, String toRevision, int pageSize) {
        return null;
    }

    @Override
    public Collection<CommitLogEntry<String>> logs(String repo, String fromRevision, String toRevision, String branch, int pageSize) {
        return null;
    }

    @Override
    public CommitLogEntry show(String repo, String revision) {
        return null;
    }

    @Override
    public List<DiffEntry> diffs(String repo, String fromRevision, String toRevision) {
        return null;
    }

    @Override
    public DiffEntry diff(String repo, String fromRevision, String toRevision, String file) {
        return null;
    }

    @Override
    public Future<byte[]> download(String repo, String filePath, String revision) {
        return null;
    }
}


/**
 *  SVN Implementation draft
 */

class SvnVCService implements VCService<Long> {

    @Override
    public Future<Void> checkout(String location, String url, String username, String password) {
        throw new UnsupportedOperationException("As all enquiries for SVN are against remote repository. This operation is not supported for SVN.");
    }

    @Override
    public Collection<CommitLogEntry<Long>> logs(String repo, int pageSize) {
        return null;
    }

    @Override
    public Collection<CommitLogEntry<Long>> logs(String repo, Long fromRevision, int pageSize) {
        return null;
    }

    @Override
    public Collection<CommitLogEntry<Long>> logs(String repo, Long fromRevision, Long toRevision, int pageSize) {
        return null;
    }

    @Override
    public Collection<CommitLogEntry<Long>> logs(String repo, Long fromRevision, String branch, int pageSize) {
        return null;
    }

    @Override
    public Collection<CommitLogEntry<Long>> logs(String repo, Long fromRevision, Long toRevision, String branch, int pageSize) {
        return null;
    }

    @Override
    public CommitLogEntry show(String repo, Long revision) {
        return null;
    }

    @Override
    public List<DiffEntry> diffs(String repo, Long fromRevision, Long toRevision) {
        return null;
    }

    @Override
    public DiffEntry diff(String repo, Long fromRevision, Long toRevision, String file) {
        return null;
    }

    @Override
    public Future<byte[]> download(String repo, String filePath, Long revision) {
        return null;
    }
}