Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.accumulo.server.master.recovery; import java.io.IOException; import org.apache.accumulo.core.conf.AccumuloConfiguration; import org.apache.accumulo.server.fs.VolumeManager; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.fs.permission.FsPermission; import org.slf4j.Logger; import org.slf4j.LoggerFactory; public class MapRLogCloser implements LogCloser { private static final Logger log = LoggerFactory.getLogger(MapRLogCloser.class); @Override public long close(AccumuloConfiguration conf, VolumeManager fs, Path path) throws IOException { log.info("Recovering file " + path.toString() + " by changing permission to readonly"); FileSystem ns = fs.getVolumeByPath(path).getFileSystem(); FsPermission roPerm = new FsPermission((short) 0444); try { ns.setPermission(path, roPerm); return 0; } catch (IOException ex) { log.error("error recovering lease ", ex); // lets do this again return 1000; } } }