/** Open an IndexWriter, executing error handling as needed. */
private IndexWriter openIndexWriter(File searchIndexPath, boolean create) throws IOException {
// NFS doesn't work with Lucene default locking as of Lucene 3.3, so use
// SimpleFSLockFactory instead.
LockFactory lockFactory = new SimpleFSLockFactory();
FSDirectory fsDirectory = FSDirectory.open(searchIndexPath, lockFactory);
IndexWriter indexWriter = null;
try {
indexWriter = new IndexWriter(fsDirectory, this.retrieveIndexWriterConfig(create));
} catch (LockObtainFailedException e) {
logger.warn(
"Unable to obtain lock for "
+ searchIndexPath.getAbsolutePath()
+ ". Attempting to forcibly unlock the index.");
if (IndexWriter.isLocked(fsDirectory)) {
try {
IndexWriter.unlock(fsDirectory);
logger.info(
"Successfully unlocked search directory " + searchIndexPath.getAbsolutePath());
} catch (IOException ex) {
logger.warn(
"Unable to unlock search directory "
+ searchIndexPath.getAbsolutePath()
+ " "
+ ex.toString());
}
}
}
if (indexWriter == null) {
// try again, there could have been a stale lock
indexWriter = new IndexWriter(fsDirectory, this.retrieveIndexWriterConfig(create));
}
return indexWriter;
}
private IndexWriter createWriter() throws IOException {
IndexWriter indexWriter = null;
try {
// release locks when started
if (IndexWriter.isLocked(store.directory())) {
logger.warn("shard is locked, releasing lock");
IndexWriter.unlock(store.directory());
}
boolean create = !IndexReader.indexExists(store.directory());
indexWriter =
new IndexWriter(
store.directory(),
analysisService.defaultIndexAnalyzer(),
create,
deletionPolicy,
IndexWriter.MaxFieldLength.UNLIMITED);
indexWriter.setMergeScheduler(mergeScheduler.newMergeScheduler());
indexWriter.setMergePolicy(mergePolicyProvider.newMergePolicy(indexWriter));
indexWriter.setSimilarity(similarityService.defaultIndexSimilarity());
indexWriter.setRAMBufferSizeMB(indexingBufferSize.mbFrac());
indexWriter.setTermIndexInterval(termIndexInterval);
} catch (IOException e) {
safeClose(indexWriter);
throw e;
}
return indexWriter;
}
/** @param indexWriter */
protected void closeIndexWrite(IndexWriter indexWriter) {
if (indexWriter != null) {
try {
indexWriter.close();
if (IndexWriter.isLocked(indexWriter.getDirectory())) {
IndexWriter.unlock(indexWriter.getDirectory());
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* 打开索引目录
*
* @param luceneDir
* @return
* @throws IOException
*/
public static FSDirectory openFSDirectory(String luceneDir) {
FSDirectory directory = null;
try {
directory = FSDirectory.open(Paths.get(luceneDir));
/**
* 注意：isLocked方法内部会试图去获取Lock,如果获取到Lock，会关闭它，否则return false表示索引目录没有被锁，
* 这也就是为什么unlock方法被从IndexWriter类中移除的原因
*/
IndexWriter.isLocked(directory);
} catch (IOException e) {
e.printStackTrace();
}
return directory;
}
/** 关闭索引 */
public void close() {
try {
try {
writer.close();
} finally {
if (IndexWriter.isLocked(dir)) {
IndexWriter.unlock(dir);
}
}
dir.close();
} catch (IOException e) {
logger.error("IOException: " + e.getMessage());
}
}
private void _checkLuceneDir() {
if (SearchEngineUtil.isIndexReadOnly()) {
return;
}
try {
Directory directory = getLuceneDir();
if (IndexWriter.isLocked(directory)) {
IndexWriter.unlock(directory);
}
} catch (Exception e) {
_log.error("Check Lucene directory failed for " + _companyId, e);
}
}
private void removeLocks() {
for (IndexType indexType : IndexType.values()) {
Directory dir = null;
try {
dir = FSDirectory.open(getIndexDirectory(indexType));
if (IndexWriter.isLocked(dir)) {
IndexWriter.unlock(dir);
LOG.info("Removed Lucene lock file in " + dir);
}
} catch (Exception x) {
LOG.warn("Failed to remove Lucene lock file in " + dir, x);
} finally {
FileUtil.closeQuietly(dir);
}
}
}
public static void checkIndex(ESLogger logger, Store store, ShardId shardId) {
if (store.tryIncRef()) {
logger.info("start check index");
try {
Directory dir = store.directory();
if (!Lucene.indexExists(dir)) {
return;
}
if (IndexWriter.isLocked(dir)) {
ESTestCase.checkIndexFailed = true;
throw new IllegalStateException("IndexWriter is still open on shard " + shardId);
}
try (CheckIndex checkIndex = new CheckIndex(dir)) {
BytesStreamOutput os = new BytesStreamOutput();
PrintStream out = new PrintStream(os, false, StandardCharsets.UTF_8.name());
checkIndex.setInfoStream(out);
out.flush();
CheckIndex.Status status = checkIndex.checkIndex();
if (!status.clean) {
ESTestCase.checkIndexFailed = true;
logger.warn(
"check index [failure] index files={}\n{}",
Arrays.toString(dir.listAll()),
new String(os.bytes().toBytes(), StandardCharsets.UTF_8));
throw new IOException("index check failure");
} else {
if (logger.isDebugEnabled()) {
logger.debug(
"check index [success]\n{}",
new String(os.bytes().toBytes(), StandardCharsets.UTF_8));
}
}
}
} catch (Exception e) {
logger.warn("failed to check index", e);
} finally {
logger.info("end check index");
store.decRef();
}
}
}
/**
* call this method once you are done with the index writer. Once all consumers have returned
* their instance, the writer will be closed and disposed
*
* @param writer
* @throws CorruptIndexException
* @throws IOException
*/
public void returnIndexWriter(IndexWriter writer) throws CorruptIndexException, IOException {
if (!lock.isHeldByCurrentThread())
throw new IllegalStateException(
"The calling thread isn't the one that obtained the writer initially");
if (writer != indexWriter)
throw new IllegalStateException("The given index writer is not the current index writer");
if (indexWriter != null) {
try {
indexWriter.close();
} finally {
indexWriter = null;
try {
if (IndexWriter.isLocked(directory)) {
IndexWriter.unlock(directory);
}
} finally {
lock.unlock();
}
}
}
}
/** @param args */
public static void main(String[] args) {
// 指定索引分词技术，这里使用的是标准分词
Analyzer anlyzer = new StandardAnalyzer(Version.LUCENE_43);
// indexwriter 配置信息
IndexWriterConfig indexWriterConfig = new IndexWriterConfig(Version.LUCENE_43, anlyzer);
// 索引的打开方式，没有索引文件就新建，有就打开
indexWriterConfig.setOpenMode(OpenMode.CREATE_OR_APPEND);
Directory directory = null;
IndexWriter indexWrite = null;
try {
// 指定索引硬盘存储路径
directory = FSDirectory.open(new File("/study/index/testindex"));
// 如果索引处于锁定状态，则解锁
if (IndexWriter.isLocked(directory)) {
IndexWriter.unlock(directory);
}
// 指定所以操作对象indexWrite
indexWrite = new IndexWriter(directory, indexWriterConfig);
} catch (Exception e) {
e.printStackTrace();
}
// 创建文档一
Document doc1 = new Document();
// 对name域赋值“测试标题”，存储域值信息
doc1.add(new TextField("name", "测试标题", Store.YES));
// 对content域赋值“测试标题”，存储域值信息
doc1.add(new TextField("content", "测试内容", Store.YES));
try {
// 将文档写入到索引中
indexWrite.addDocument(doc1);
} catch (Exception e) {
e.printStackTrace();
}
// 创建文档二
Document doc2 = new Document();
doc2.add(new TextField("name", "基于lucene的案例开发：索引数学模型", Store.YES));
doc2.add(
new TextField(
"content",
"lucene将一篇文档分成若干个域，每个域又分成若干个词元，通过词元在文档中的重要程度，将文档转化为N维的空间向量，通过计算两个向量之间的夹角余弦值来计算两个文档的相似程度",
Store.YES));
try {
// 将文档写入到索引中
indexWrite.addDocument(doc2);
} catch (Exception e) {
e.printStackTrace();
}
// 将indexWrite操作提交，如果不提交，之前的操作将不会保存到硬盘
try {
// 这一步很消耗系统资源，所以commit操作需要有一定的策略
indexWrite.commit();
// 关闭资源
indexWrite.close();
directory.close();
} catch (Exception e) {
e.printStackTrace();
}
}