| /* |
| * 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.jackrabbit.vault.fs.io; |
| |
| import java.util.HashSet; |
| import java.util.Set; |
| |
| import javax.jcr.RepositoryException; |
| import javax.jcr.Session; |
| |
| import org.apache.jackrabbit.vault.fs.spi.ProgressTracker; |
| import org.jetbrains.annotations.NotNull; |
| import org.jetbrains.annotations.Nullable; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * {@code AutoSave}... |
| */ |
| public class AutoSave { |
| |
| /** |
| * default logger |
| */ |
| private static final Logger log = LoggerFactory.getLogger(AutoSave.class); |
| |
| /** |
| * number of modified nodes |
| */ |
| private int numModified; |
| |
| /** |
| * number of modified nodes at last save |
| */ |
| private int lastSave; |
| |
| /** |
| * number of modified nodes that trigger a save. default is 1024 |
| */ |
| private int threshold = 1024; |
| |
| /** |
| * set that records the missing mandatory items. save has to be delay until they are resolved |
| */ |
| private final Set<String> missingMandatory = new HashSet<String>(); |
| |
| /** |
| * tracker to use to report progress messages |
| */ |
| private ProgressTracker tracker; |
| |
| /** |
| * flag controlling if autosave should until simulate |
| */ |
| private boolean dryRun; |
| |
| /** |
| * debug setting that allows to simulate autosave failures. |
| */ |
| private int debugFailEach; |
| |
| /** |
| * debug counter used to trigger failures |
| */ |
| private int debugSaveCount; |
| |
| public AutoSave() { |
| } |
| |
| public AutoSave(int threshold) { |
| this.threshold = threshold; |
| } |
| |
| public AutoSave copy() { |
| AutoSave ret = new AutoSave(); |
| ret.threshold = threshold; |
| ret.numModified = numModified; |
| ret.lastSave = lastSave; |
| ret.tracker = tracker; |
| ret.dryRun = dryRun; |
| ret.missingMandatory.addAll(missingMandatory); |
| ret.debugFailEach = debugFailEach; |
| // don't copy save count, otherwise it will fail for ever. |
| // ret.debugSaveCount = debugSaveCount; |
| return ret; |
| } |
| |
| public void setTracker(@Nullable ProgressTracker tracker) { |
| this.tracker = tracker; |
| } |
| |
| public boolean isDryRun() { |
| return dryRun; |
| } |
| |
| public void setDryRun(boolean dryRun) { |
| this.dryRun = dryRun; |
| } |
| |
| /** |
| * Debug settings to allows to produce failures after each {@code debugFailEach} save. |
| * @param debugFailEach cardinal indicating when to fail |
| */ |
| public void setDebugFailEach(int debugFailEach) { |
| this.debugFailEach = debugFailEach; |
| } |
| |
| /** |
| * Returns {@code true} if more than {@link #getThreshold()} nodes are |
| * modified. |
| * @return {@code true} if threshold reached. |
| */ |
| public boolean needsSave() { |
| boolean res = (numModified - lastSave) >= threshold; |
| if (res && !missingMandatory.isEmpty()) { |
| log.debug("Threshold of {} reached but still unresolved mandatory items.", threshold); |
| res = false; |
| } |
| return res; |
| } |
| |
| /** |
| * saves the changes under the given node and resets the counter |
| * @param session the session to save. can be {@code null} |
| * @throws RepositoryException if an error occurs. |
| */ |
| public void save(@Nullable Session session) throws RepositoryException { |
| if (threshold == Integer.MAX_VALUE) { |
| log.trace("Save disabled."); |
| return; |
| } |
| int diff = numModified - lastSave; |
| log.debug("Threshold of {} reached. {} approx {} transient changes. {} unresolved", new Object[]{ |
| threshold, |
| dryRun ? "dry run, reverting" : "saving", |
| diff, |
| missingMandatory.size() |
| }); |
| if (tracker != null) { |
| if (dryRun) { |
| tracker.track("reverting approx " + diff + " nodes... (dry run)", ""); |
| } else { |
| tracker.track("saving approx " + diff + " nodes...", ""); |
| } |
| } |
| if (session != null) { |
| if (debugFailEach > 0 && debugSaveCount > 0 && debugSaveCount%debugFailEach == 0) { |
| String msg = String.format("Debugging provoked failure after %s saves.", debugSaveCount); |
| log.error(msg); |
| throw new RepositoryException(msg); |
| } |
| |
| if (dryRun) { |
| session.refresh(false); |
| } else { |
| try { |
| session.save(); |
| debugSaveCount++; |
| } catch (RepositoryException e) { |
| log.error("error during auto save - retrying after refresh..."); |
| session.refresh(true); |
| session.save(); |
| debugSaveCount++; |
| } |
| } |
| } |
| lastSave = numModified; |
| } |
| |
| /** |
| * Returns the threshold |
| * @return the threshold |
| */ |
| public int getThreshold() { |
| return threshold; |
| } |
| |
| /** |
| * Sets the threshold |
| * @param threshold the threshold |
| */ |
| public void setThreshold(int threshold) { |
| this.threshold = threshold; |
| } |
| |
| /** |
| * Adds {@code num} modified |
| * @param num number of modified |
| * @return {@code true} if threshold is reached |
| */ |
| public boolean modified(int num) { |
| numModified+= num; |
| return needsSave(); |
| } |
| |
| public void markMissing(@NotNull String path) { |
| missingMandatory.add(path); |
| } |
| |
| public void markResolved(@NotNull String path) { |
| missingMandatory.remove(path); |
| } |
| |
| @Override |
| public String toString() { |
| return String.valueOf(threshold); |
| } |
| } |