[PATCH]: Forking benchmarks with long classpath on Windows (7)

[Dávid Karnok]

Index: jmh-core/src/main/java/org/openjdk/jmh/runner/Runner.java
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
--- jmh-core/src/main/java/org/openjdk/jmh/runner/Runner.java (revision
1434:1ddf31f810a3100b9433c3fedf24615e85b1d1a7)
+++ jmh-core/src/main/java/org/openjdk/jmh/runner/Runner.java (revision
1434+:1ddf31f810a3+)
@@ -47,6 +47,8 @@
 import java.nio.channels.OverlappingFileLockException;
 import java.util.*;
 import java.util.concurrent.TimeUnit;
+import java.util.jar.*;
+import java.util.zip.*;

 /**
  * Runner executes JMH benchmarks.
@@ -826,7 +828,34 @@
         // assemble final process command
         command.add("-cp");
         if (Utils.isWindows()) {
-            command.add('"' + System.getProperty("java.class.path") + '"');
+            try {
+                File tmpFile = File.createTempFile("jmh-classpath-file",
".jar");
+                tmpFile.deleteOnExit();
+
+                StringBuilder pw = new StringBuilder();
+                for (String cp :
System.getProperty("java.class.path").split(";")) {
+                    pw.append("/");
+                    pw.append(cp.replace('\\', '/').replace(" ", "%20"));
+                    if (!cp.endsWith(".jar")) {
+                        pw.append('/');
+                    }
+                    pw.append(" ");
+                }
+
+                Manifest manifest = new Manifest();
+                Attributes attributes = manifest.getMainAttributes();
+                attributes.put(Attributes.Name.MANIFEST_VERSION, "1.0");
+                attributes.putValue("Class-Path", pw.toString().trim());
+
+                try (JarOutputStream zout = new JarOutputStream(new
FileOutputStream(tmpFile), manifest)) {
+                    ZipEntry ze = new ZipEntry("META-INF/");
+                    zout.putNextEntry(ze);
+                }
+
+                command.add("\"" + tmpFile.getAbsolutePath() + "\"");
+            } catch (IOException ex) {
+                command.add('"' + System.getProperty("java.class.path") +
'"');
+            }
         } else {
             command.add(System.getProperty("java.class.path"));
         }






2017-12-21 8:24 GMT+01:00 Aleksey Shipilev <shade at redhat.com>:

> Hi David,
>
> On 12/12/2017 11:36 AM, Dávid Karnok wrote:
> > I'd like to submit a patch (attached) to JMH's
> > org.openjdk.jmh.runner.Runner.java that creates a temporary jar file
> with
> > all classpath entries on Windows so that the command line doesn't
> overflow.
>
> The patch got stripped by the mailing list, apparently. (Wrong MIME type?)
>
> Thanks,
> -Aleksey
>
>


-- 
Best regards,
David Karnok