如何将gzip压缩的rdf文件加载到rdf4j存储库? [英] How to load a gzipped rdf file to rdf4j Repository?
问题描述
我想将gzip压缩的rdf文件加载到org.eclipse.rdf4j.repository.Repository
中.在上载期间,必须将状态消息记录到控制台.我的rdf文件的大小是〜1GB的未压缩或〜50MB的压缩数据.
I want to load a gzipped rdf file into a org.eclipse.rdf4j.repository.Repository
. During the upload, status messages must be logged to the console. The size of my rdf file is ~1GB of uncompressed or ~50MB of compressed data.
推荐答案
变体1
以下示例将带有压缩数据的InputStream
加载到内存中的rdf存储库中. rdf4j直接支持压缩格式.
使用RepositoryConnectionListenerAdapter
,每100000条语句将被打印到stdout.
Variant 1
The following sample will load an InputStream
with gzipped data into an in-memory rdf repository. The zipped format is supported directly by rdf4j.
Every 100000th statement will be printed to stdout using the RepositoryConnectionListenerAdapter
.
import java.io.InputStream;
import org.eclipse.rdf4j.model.IRI;
import org.eclipse.rdf4j.model.Resource;
import org.eclipse.rdf4j.model.Value;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;
import org.eclipse.rdf4j.repository.event.base.NotifyingRepositoryConnectionWrapper;
import org.eclipse.rdf4j.repository.event.base.RepositoryConnectionListenerAdapter;
import org.eclipse.rdf4j.repository.sail.SailRepository;
import org.eclipse.rdf4j.rio.RDFFormat;
import org.eclipse.rdf4j.sail.memory.MemoryStore;
public class MyTripleStore {
Repository repo;
/**
* Creates an inmemory triple store
*
*/
public MyTripleStore() {
repo = new SailRepository(new MemoryStore());
repo.initialize();
}
/**
* @param in gzip compressed data on an inputstream
* @param format the format of the streamed data
*/
public void loadZippedFile(InputStream in, RDFFormat format) {
System.out.println("Load zip file of format " + format);
try (NotifyingRepositoryConnectionWrapper con =
new NotifyingRepositoryConnectionWrapper(repo, repo.getConnection());) {
RepositoryConnectionListenerAdapter myListener =
new RepositoryConnectionListenerAdapter() {
private long count = 0;
@Override
public void add(RepositoryConnection arg0, Resource arg1, IRI arg2,
Value arg3, Resource... arg4) {
count++;
if (count % 100000 == 0)
System.out.println("Add statement number " + count + "\n"
+ arg1+ " " + arg2 + " " + arg3);
}
};
con.addRepositoryConnectionListener(myListener);
con.add(in, "", format);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
变种2
此变体实现AbstractRDFHandler
来提供报告.
Variant 2
This variant implements an AbstractRDFHandler
to provide the reporting.
import java.io.InputStream;
import org.eclipse.rdf4j.model.Statement;
import org.eclipse.rdf4j.repository.Repository;
import org.eclipse.rdf4j.repository.RepositoryConnection;
import org.eclipse.rdf4j.repository.sail.SailRepository;
import org.eclipse.rdf4j.repository.util.RDFInserter;
import org.eclipse.rdf4j.repository.util.RDFLoader;
import org.eclipse.rdf4j.rio.RDFFormat;
import org.eclipse.rdf4j.rio.helpers.AbstractRDFHandler;
import org.eclipse.rdf4j.sail.memory.MemoryStore;
public class MyTripleStore {
Repository repo;
/**
* Creates an inmemory triple store
*
*/
public MyTripleStore() {
repo = new SailRepository(new MemoryStore());
repo.initialize();
}
/**
* @param in gzip compressed data on an inputstream
* @param format the format of the streamed data
*/
public void loadZippedFile1(InputStream in, RDFFormat format) {
try (RepositoryConnection con = repo.getConnection()) {
MyRdfInserter inserter = new MyRdfInserter(con);
RDFLoader loader =
new RDFLoader(con.getParserConfig(), con.getValueFactory());
loader.load(in, "", RDFFormat.NTRIPLES, inserter);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
class MyRdfInserter extends AbstractRDFHandler {
RDFInserter rdfInserter;
int count = 0;
public MyRdfInserter(RepositoryConnection con) {
rdfInserter = new RDFInserter(con);
}
@Override
public void handleStatement(Statement st) {
count++;
if (count % 100000 == 0)
System.out.println("Add statement number " + count + "\n"
+ st.getSubject().stringValue() + " "
+ st.getPredicate().stringValue() + " "
+ st.getObject().stringValue());
rdfInserter.handleStatement(st);
}
}
}
在这里,如何调用代码
MyTripleStore ts = new MyTripleStore();
ts.loadZippedFile(new FileInputStream("your-ntriples-zipped.gz"),
RDFFormat.NTRIPLES);
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