判断是否为文件，如果file为null，则返回false

@param path 文件
@param isFollowLinks 是否跟踪软链（快捷方式）
@return 如果为文件true
497690
public static boolean isFile(Path path, boolean isFollowLinks) {
		if (null == path) {
			return false;
		}
		final LinkOption[] options = isFollowLinks ? new LinkOption[0] : new LinkOption[] { LinkOption.NOFOLLOW_LINKS };
		return Files.isRegularFile(path, options);
	}
529871
public static function isAllowedAbsPath($path) {
		if (self::isAbsPath($path) &&
				self::validPathStr($path) &&
				(self::isFirstPartOfStr($path, PATH_site)
						||
						($GLOBALS['TYPO3_CONF_VARS']['BE']['lockRootPath'] && self::isFirstPartOfStr($path, $GLOBALS['TYPO3_CONF_VARS']['BE']['lockRootPath']))
				)
		) {
			return TRUE;
		}
	}
816093
public boolean matches(String[] path) {
		if (nbAny == 0 && path.length != nbWildcards)
			return false;
		if (path.length < nbWildcards)
			return false;
		return check(path, 0, 0, nbWildcards, nbAny);
	}
464258
public static boolean isZipFile(Path path) {
        return Files.isRegularFile(path) && path.toString().toLowerCase().endsWith(".zip");
    }
201683
public boolean hasPath(String path) {
        Props props = pathMap.get(path);
        return props != null && !props.isEmpty();
    }
800420
public static boolean isAbsolutePath (final String path) {
        if (path == null || path.trim().length() == 0) {
            return false;
        }

        if (File.separator.equals(UNIX_SEPARATOR)) {
            return path.startsWith(UNIX_SEPARATOR);
        } else

        if (File.separator.equals(WINDOWS_SEPARATOR) && path.length() > 2) {
            return path.matches("([a-zA-Z]:|\\\\)\\\\.*");
        }

        return false;
    }
1184671
@Override
	public boolean isDirectory(String path) {

		String resourcePath = getResolver().getResourcePath(path);
		return rsBrowser.isDirectory(resourcePath);
	}
391296
private boolean isInZkWathcedNamespacePaths(String path) {
        if (StringUtil.isEmpty(path)) {
            return false;
        }
        for (String watchNamespacePath : RpcClientConf.ZK_WATCH_NAMESPACE_PATHS) {
            if (StringUtil.isEmpty(watchNamespacePath)) {
                continue;
            }
            if (path.contains(watchNamespacePath)) {
                return true;
            }
        }
        return false;
    }
758255
function isAtRoot(path) {
		if (!path) {
			return false;
		}
		if (path === "/workspace") {
			return true; // sad but true
		}
		var pathUrl = new URL(path, window.location.href);
		return pathUrl.href.indexOf(_workspaceUrlHref) === 0; //$NON-NLS-0$
	}
122893
public static boolean isBELScript(final String path) {
        if (path == null) {
            return false;
        }
        if (path.endsWith(BEL_SCRIPT_EXTENSION)) {
            return true;
        }
        return false;
    }
759966
private boolean isMap(PropertyPath path) {
        if (schemaRoot != null) {
            Schema schema = this.schemaRoot.find(path);
            return schema != null && (schema.hasChild(NodeId.ANY_KEY) || schema.hasChild(NodeId.ANY));
        }
        return false;
    }
911723
public synchronized boolean contains(RelativePath path) {
        try {
            checkIndex();
            return getZipIndexEntry(path) != null;
        }
        catch (IOException e) {
            return false;
        }
    }
1236681
public boolean znodeIsMe(String path) {
        String value = ZKUtils.get(zk, path);
        return (value != null && value == myNodeID);
    }
232371
public boolean existFile(String path) {
		FTPFile[] ftpFileArr;
		try {
			ftpFileArr = client.listFiles(path);
		} catch (IOException e) {
			throw new FtpException(e);
		}
		if (ArrayUtil.isNotEmpty(ftpFileArr)) {
			return true;
		}
		return false;
	}
817358
public static boolean isAbsoluteAndSchemeAuthorityNull(Path path) {
    return (path.isAbsolute() &&
        path.toUri().getScheme() == null && path.toUri().getAuthority() == null);
  }
1333199
protected boolean isValidPath(String path) {
        if (path == null) {
            return false;
        }
        
        if (!PATH_PATTERN.matcher(path).matches()) {
            return false;
        }
        
        try {
            URI uri = new URI(null,null,path,null);
            String norm = uri.normalize().getPath();
            if (norm.startsWith("/../") // Trying to go via the parent dir 
                    || norm.equals("/..")) {   // Trying to go to the parent dir
                return false;
            }
        } catch (URISyntaxException e) {
            return false;
        }
        
        int slash2Count = countToken("//", path);
        if (isOff(ALLOW_2_SLASHES) && (slash2Count > 0)) {
            return false;
        }
        
        return true;
    }
51814
public boolean isSameFile(JimfsPath path, FileSystemView view2, JimfsPath path2)
      throws IOException {
    if (!isSameFileSystem(view2)) {
      return false;
    }

    store.readLock().lock();
    try {
      File file = lookUp(path, Options.FOLLOW_LINKS).fileOrNull();
      File file2 = view2.lookUp(path2, Options.FOLLOW_LINKS).fileOrNull();
      return file != null && Objects.equals(file, file2);
    } finally {
      store.readLock().unlock();
    }
  }