Java tutorial
/* * This library is free software; you can redistribute it and/or modify * it under the terms of the GNU Library General Public License as * published by the Free Software Foundation; either version 2 of the * License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this program (see the file COPYING.LIB for more * details); if not, write to the Free Software Foundation, Inc., * 675 Mass Ave, Cambridge, MA 02139, USA. */ package org.dcache.chimera; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.dao.DuplicateKeyException; import org.springframework.dao.IncorrectUpdateSemanticsDataAccessException; import javax.sql.DataSource; import java.io.File; import java.sql.Timestamp; import java.util.ArrayList; import java.util.Collections; import java.util.EnumSet; import java.util.List; import org.dcache.acl.enums.AceFlags; import org.dcache.acl.enums.RsType; import org.dcache.chimera.posix.Stat; /** * PostgreSQL specific * * */ public class PgSQLFsSqlDriver extends FsSqlDriver { /** * logger */ private static final Logger _log = LoggerFactory.getLogger(PgSQLFsSqlDriver.class); /** * this is a utility class which is issues SQL queries on database * */ public PgSQLFsSqlDriver(DataSource dataSource) throws ChimeraFsException { super(dataSource); _log.info("Running PostgreSQL specific Driver"); } @Override protected FsInode createInodeInParent(FsInode parent, String name, String id, int owner, int group, int mode, int type, int nlink, long size) { Timestamp now = new Timestamp(System.currentTimeMillis()); Long inumber = _jdbc.query("SELECT f_create_inode(?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)", cs -> { cs.setLong(1, parent.ino()); cs.setString(2, name); cs.setString(3, id); cs.setInt(4, type); cs.setInt(5, mode & UnixPermission.S_PERMS); cs.setInt(6, nlink); cs.setInt(7, owner); cs.setInt(8, group); cs.setLong(9, size); cs.setInt(10, _ioMode); cs.setTimestamp(11, now); }, rs -> rs.next() ? rs.getLong(1) : null); if (inumber == null) { throw new IncorrectUpdateSemanticsDataAccessException("f_create_inode failed to return an inumber."); } Stat stat = new Stat(); stat.setIno(inumber); stat.setId(id); stat.setCrTime(now.getTime()); stat.setGeneration(0); stat.setSize(size); stat.setATime(now.getTime()); stat.setCTime(now.getTime()); stat.setMTime(now.getTime()); stat.setUid(owner); stat.setGid(group); stat.setMode(mode & UnixPermission.S_PERMS | type); stat.setNlink(nlink); stat.setDev(17); stat.setRdev(13); return new FsInode(parent.getFs(), inumber, FsInodeType.INODE, 0, stat); } @Override boolean removeInodeIfUnlinked(FsInode inode) { return _jdbc.update("DELETE FROM t_inodes WHERE inumber=? AND inlink = 0", inode.ino()) > 0; } /** * * return the path associated with inode, starting from root of the tree. * in case of hard link, one of the possible paths is returned * * @param inode * @return */ @Override String inode2path(FsInode inode, FsInode startFrom) { return _jdbc.query("SELECT inumber2path(?)", ps -> ps.setLong(1, inode.ino()), rs -> rs.next() ? rs.getString(1) : null); } /** * Returns a normalized path string for the given path. The * normalized string uses the slash character as a path separator, * it does not have a leading slash (i.e. it is relative), and it * has no empty path elements. */ private String normalizePath(String path) { File file = new File(path); List<String> elements = new ArrayList<>(); do { String fileName = file.getName(); if (fileName.length() != 0) { /* * skip multiple '/' */ elements.add(fileName); } file = file.getParentFile(); } while (file != null); StringBuilder normalizedPath = new StringBuilder(); if (!elements.isEmpty()) { normalizedPath.append(elements.get(elements.size() - 1)); for (int i = elements.size() - 2; i >= 0; i--) { normalizedPath.append('/').append(elements.get(i)); } } return normalizedPath.toString(); } /** * get inode of given path starting <i>root</i> inode. * @param root staring point * @param path * @return inode or null if path does not exist. */ @Override FsInode path2inode(FsInode root, String path) throws ChimeraFsException { /* Ideally we would use the SQL array type for the second * parameter to inject the path elements, however there is no * easy way to do that with prepared statements. Hence we use * a slash delimited string instead. We cannot use * <code>path</code> as that uses the platform specific path * separator. */ String normalizedPath = normalizePath(path); if (normalizedPath.length() == 0) { return root; } return _jdbc.query("SELECT path2inumber(?, ?)", ps -> { ps.setLong(1, root.ino()); ps.setString(2, normalizedPath); }, rs -> { if (rs.next()) { long id = rs.getLong(1); if (!rs.wasNull()) { return new FsInode(root.getFs(), id); } } return null; }); } @Override List<FsInode> path2inodes(FsInode root, String path) throws ChimeraFsException { /* Ideally we would use the SQL array type for the second * parameter to inject the path elements, however there is no * easy way to do that with prepared statements. Hence we use * a slash delimited string instead. We cannot use * <code>path</code> as that uses the platform specific path * separator. */ String normalizedPath = normalizePath(path); if (normalizedPath.isEmpty()) { return Collections.singletonList(root); } return _jdbc.query( "SELECT inumber,ipnfsid,isize,inlink,itype,imode,iuid,igid,iatime,ictime,imtime from path2inodes(?, ?)", ps -> { ps.setLong(1, root.ino()); ps.setString(2, normalizedPath); }, (rs, rowNum) -> { FsInode inode = new FsInode(root.getFs(), rs.getLong("inumber")); Stat stat = new Stat(); stat.setIno(rs.getLong("inumber")); stat.setId(rs.getString("ipnfsid")); stat.setSize(rs.getLong("isize")); stat.setATime(rs.getTimestamp("iatime").getTime()); stat.setCTime(rs.getTimestamp("ictime").getTime()); stat.setMTime(rs.getTimestamp("imtime").getTime()); stat.setUid(rs.getInt("iuid")); stat.setGid(rs.getInt("igid")); stat.setMode(rs.getInt("imode") | rs.getInt("itype")); stat.setNlink(rs.getInt("inlink")); stat.setDev(17); inode.setStatCache(stat); return inode; }); } @Override void copyAcl(FsInode source, FsInode inode, RsType type, EnumSet<AceFlags> mask, EnumSet<AceFlags> flags) { int msk = mask.stream().mapToInt(AceFlags::getValue).reduce(0, (a, b) -> a | b); int flgs = flags.stream().mapToInt(AceFlags::getValue).reduce(0, (a, b) -> a | b); _jdbc.update("INSERT INTO t_acl (inumber,rs_type,type,flags,access_msk,who,who_id,ace_order) " + "SELECT ?, ?, type, (flags | ?) # ?, access_msk, who, who_id, ace_order " + "FROM t_acl WHERE inumber = ? AND ((flags & ?) > 0)", ps -> { ps.setLong(1, inode.ino()); ps.setInt(2, type.getValue()); ps.setInt(3, msk); ps.setInt(4, msk); ps.setLong(5, source.ino()); ps.setInt(6, flgs); }); } @Override void createEntryInParent(FsInode parent, String name, FsInode inode) { int n = _jdbc.update( "insert into t_dirs (iparent, iname, ichild) " + "(select ? as iparent, ? as iname, ? as ichild " + " where not exists (select 1 from t_dirs where iparent=? and iname=?))", ps -> { ps.setLong(1, parent.ino()); ps.setString(2, name); ps.setLong(3, inode.ino()); ps.setLong(4, parent.ino()); ps.setString(5, name); }); if (n == 0) { /* * no updates as such entry already exists. * To be compatible with others, throw corresponding * DataAccessException. */ throw new DuplicateKeyException("Entry already exists"); } } @Override void addInodeLocation(FsInode inode, int type, String location) { Timestamp now = new Timestamp(System.currentTimeMillis()); _jdbc.update("INSERT INTO t_locationinfo (inumber,itype,ilocation,ipriority,ictime,iatime,istate) " + "(SELECT ?,?,?,?,?,?,? WHERE NOT EXISTS " + "(SELECT 1 FROM t_locationinfo WHERE inumber=? AND itype=? AND ilocation=?))", ps -> { ps.setLong(1, inode.ino()); ps.setInt(2, type); ps.setString(3, location); ps.setInt(4, 10); // default priority ps.setTimestamp(5, now); ps.setTimestamp(6, now); ps.setInt(7, 1); // online ps.setLong(8, inode.ino()); ps.setInt(9, type); ps.setString(10, location); }); } }