Java 进程挂在 IOUtils 上。疑似僵局

Question

我有一个 java 进程挂在调用中，IOUtils.toString使用以下代码：

String html = "";
try {
    html = IOUtils.toString(someUrl.openStream(), "utf-8"); // process hangs on this line
} catch (Exception e) {
    return null;
}

它无法可靠地重现这一点。它是网络爬虫的一部分，因此成功执行了该行数千次，但最终导致该进程在几天后挂起。

jstack 的输出：

2013-09-25 09:09:36
Full thread dump OpenJDK 64-Bit Server VM (20.0-b12 mixed mode):

"Attach Listener" daemon prio=10 tid=0x00007f2b1c001000 nid=0x225a waiting on condition [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"Thread-0" prio=10 tid=0x00007f2b34122000 nid=0x187b runnable [0x00007f2b30970000]
   java.lang.Thread.State: RUNNABLE
        at java.net.SocketInputStream.socketRead0(Native Method)
        at java.net.SocketInputStream.read(SocketInputStream.java:146)
        at java.io.BufferedInputStream.fill(BufferedInputStream.java:235)
        at java.io.BufferedInputStream.read1(BufferedInputStream.java:275)
        at java.io.BufferedInputStream.read(BufferedInputStream.java:334)
        - locked <0x00000000e3d2d160> (a java.io.BufferedInputStream)
        at sun.net.www.http.ChunkedInputStream.readAheadBlocking(ChunkedInputStream.java:552)
        at sun.net.www.http.ChunkedInputStream.readAhead(ChunkedInputStream.java:609)
        at sun.net.www.http.ChunkedInputStream.read(ChunkedInputStream.java:696)
        - locked <0x00000000e3d30558> (a sun.net.www.http.ChunkedInputStream)
        at java.io.FilterInputStream.read(FilterInputStream.java:133)
        at sun.net.www.protocol.http.HttpURLConnection$HttpInputStream.read(HttpURLConnection.java:2582)
        at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:282)
        at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:324)
        at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:176)
        - locked <0x00000000e3d317d0> (a java.io.InputStreamReader)
        at java.io.InputStreamReader.read(InputStreamReader.java:184)
        at java.io.Reader.read(Reader.java:140)
        at org.apache.commons.io.IOUtils.copyLarge(IOUtils.java:1364)
        at org.apache.commons.io.IOUtils.copy(IOUtils.java:1340)
        at org.apache.commons.io.IOUtils.copy(IOUtils.java:1315)
        at org.apache.commons.io.IOUtils.toString(IOUtils.java:525)

我看不到在 toString 方法上设置超时的任何方法。有什么建议？这是 Apache Commons 中的错误吗？或者在我的 OpenJDK 中？

Answer 1

我决定尝试简单地使用 guava IO 来代替，因为它已经在我的类路径中了：

String html = "";
try {
    InputSupplier<? extends InputStream> supplier = Resources
            .newInputStreamSupplier(metaUrl);
    html = CharStreams.toString(CharStreams.newReaderSupplier(supplier,
            Charsets.UTF_8));
} catch (Exception e) {
    return null;
}

通常需要几天的时间才会崩溃，所以如果我在几天内没有更新这个答案，假设这有效！

更新：到目前为止 7 天没有挂起...:)