java.lang.OutOfMemoryError：调用Files.readAllBytes时直接缓冲内存

Question

我有以下代码，旨在读取目录并将其压缩到tar.gz归档文件中。当我将代码部署到服务器上并使用一批文件对其进行测试时，它可以在前几个测试批处理中使用，但是在第4批或第5批处理之后，它将始终如一地为我提供java.lang.OutOfMemoryError：即使直接缓冲内存文件批处理大小保持不变，并且堆空间看起来不错。这是代码：

public static void compressDirectory(String archiveDirectoryToCompress) throws IOException {
Path archiveToCompress = Files.createFile(Paths.get(archiveDirectoryToCompress + ".tar.gz"));

try (GzipCompressorOutputStream gzipCompressorOutputStream = new GzipCompressorOutputStream(
    Files.newOutputStream(archiveToCompress));
     TarArchiveOutputStream tarArchiveOutputStream = new TarArchiveOutputStream(gzipCompressorOutputStream)) {
  Path directory = Paths.get(archiveDirectoryToCompress);
  Files.walk(directory)
      .filter(path -> !Files.isDirectory(path))
      .forEach(path -> {
        String
            stringPath =
            path.toAbsolutePath().toString().replace(directory.toAbsolutePath().toString(), "")
                .replace(path.getFileName().toString(), "");
        TarArchiveEntry tarEntry = new TarArchiveEntry(stringPath + "/" + path.getFileName().toString());
        try {
          byte[] bytes = Files.readAllBytes(path); //It throws the error at this point.
          tarEntry.setSize(bytes.length);
          tarArchiveOutputStream.putArchiveEntry(tarEntry);
          tarArchiveOutputStream.write(bytes);
          tarArchiveOutputStream.closeArchiveEntry();
        } catch (Exception e) {
          LOGGER.error("There was an error while compressing the files", e);
        }
      });
}

}

这是一个例外：

Caused by: java.lang.OutOfMemoryError: Direct buffer memory
    at java.nio.Bits.reserveMemory(Bits.java:658)
    at java.nio.DirectByteBuffer.<init>(DirectByteBuffer.java:123)
    at java.nio.ByteBuffer.allocateDirect(ByteBuffer.java:311)
    at sun.nio.ch.Util.getTemporaryDirectBuffer(Util.java:174)
    at sun.nio.ch.IOUtil.read(IOUtil.java:195)
    at sun.nio.ch.FileChannelImpl.read(FileChannelImpl.java:158)
    at sun.nio.ch.ChannelInputStream.read(ChannelInputStream.java:65)
    at sun.nio.ch.ChannelInputStream.read(ChannelInputStream.java:109)
    at sun.nio.ch.ChannelInputStream.read(ChannelInputStream.java:103)
    at java.nio.file.Files.read(Files.java:3105)
    at java.nio.file.Files.readAllBytes(Files.java:3158)
    at com.ubs.gfs.etd.reporting.otc.trsloader.service.file.GmiEodFileArchiverService.lambda$compressDirectory$4(GmiEodFileArchiverService.java:124)
    at com.ubs.gfs.etd.reporting.otc.trsloader.service.file.GmiEodFileArchiverService$$Lambda$19/183444013.accept(Unknown Source)
    at java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:184)
    at java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:175)
    at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193)
    at java.util.Iterator.forEachRemaining(Iterator.java:116)
    at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1801)
    at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:512)
    at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:502)
    at java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:151)
    at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:174)
    at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
    at java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:418)
    at com.ubs.gfs.etd.reporting.otc.trsloader.service.file.GmiEodFileArchiverService.compressDirectory(GmiEodFileArchiverService.java:117)
    at com.ubs.gfs.etd.reporting.otc.trsloader.service.file.GmiEodFileArchiverService.archiveFiles(GmiEodFileArchiverService.java:66)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.springframework.expression.spel.support.ReflectiveMethodExecutor.execute(ReflectiveMethodExecutor.java:113)
    at org.springframework.expression.spel.ast.MethodReference.getValueInternal(MethodReference.java:102)
    at org.springframework.expression.spel.ast.MethodReference.access$000(MethodReference.java:49)
    at org.springframework.expression.spel.ast.MethodReference$MethodValueRef.getValue(MethodReference.java:347)
    at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:88)
    at org.springframework.expression.spel.ast.SpelNodeImpl.getTypedValue(SpelNodeImpl.java:131)
    at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:330)
    at org.springframework.integration.util.AbstractExpressionEvaluator.evaluateExpression(AbstractExpressionEvaluator.java:166)
    at org.springframework.integration.util.MessagingMethodInvokerHelper.processInternal(MessagingMethodInvokerHelper.java:317)
    ... 93 more

我认为有一个缓冲区内存泄漏，因为它在前4个测试批次上都可以正常工作，但随后始终给出java.lang.OutOfMemoryError：之后出现直接缓冲区错误，但我不知道如何解决。我在这里看到了使用Cleaner方法的潜在解决方案：http :
//www.java67.com/2014/01/how-to-fix-javalangoufofmemoryerror-direct-byte-
buffer-java.html

但我不知道这种情况是否适用。

- - - - - - - - - - - - 编辑 - - - - - - - - - - - -

我找到了另一种有关如何使用IOUtils和缓冲的输入流来对文件进行tar处理的方法，并解决了该问题，即更新了代码：

  public static void compressDirectory(String archiveDirectoryToCompress) throws IOException {
Path archiveToCompress = Files.createFile(Paths.get(archiveDirectoryToCompress + ".tar.gz"));

try (GzipCompressorOutputStream gzipCompressorOutputStream = new GzipCompressorOutputStream(
    Files.newOutputStream(archiveToCompress));
     TarArchiveOutputStream tarArchiveOutputStream = new TarArchiveOutputStream(gzipCompressorOutputStream)) {
  Path directory = Paths.get(archiveDirectoryToCompress);
  Files.walk(directory)
      .filter(path -> !Files.isDirectory(path))
      .forEach(path -> {
        TarArchiveEntry tarEntry = new TarArchiveEntry(path.toFile(),path.getFileName().toString());
        try (BufferedInputStream bufferedInputStream = new BufferedInputStream(new FileInputStream(path.toString()))) {
          tarArchiveOutputStream.putArchiveEntry(tarEntry);
          IOUtils.copy(bufferedInputStream, tarArchiveOutputStream);
          tarArchiveOutputStream.closeArchiveEntry();
        } catch (Exception e) {
          LOGGER.error("There was an error while compressing the files", e);
        }
      });
}

}

Answer 1

实际上，只需调用即可获取文件大小file.length()。尝试更改从文件读取字节的方式：

tarArchiveOutputStream.write(IOUtils.toByteArray(new FileInputStream(path.toFile())));

来自apache commons IO包（http://commons.apache.org/proper/commons-
io/
）的IOUtils类。我认为这应该有助于解决您的麻烦。在某些情况下，建议使用@afretas。