Consider the following two URLs:
jar:file:/test.jar!/BOOT-INF/classes!/foo.txt
jar:file:/test.jar!/BOOT-INF/classes/foo.txt
They both reference the same foo.txt file in the BOOT-INF/classes
directory of test.jar, however the first URL does so via the
nested BOOT-INF/classes archive. Previously, this difference in the
URLs would lead to PathMatchingResourcePatternResolver returning two
resources for foo.txt when asked to find all resources matching the
pattern classpath*:/**/*.txt.
This commit updates our Handler that is used for jar: URLs to consider
the two URLs above to be equivalent such that url1 is equal to url2
and the two urls will produce the same hash code.
Closes gh-7449
Previously, if Boot's JarURLConnection pointed to the root of a nested
entry, e.g. /BOOT-INF/classes, a call to getInputStream() would throw
an IOException. This behavior is reasonable for a URL that points
to the root of a normal jar as the jar itself is on the class path
anyway. However, for a nested jar it meant that a call to
ClassLoader.getResources("") would not include URLs for any nested
jars and directories (/BOOT-INF/classes and jars in /BOOT-INF/lib).
This is due to some logic in URLClassPath.Loader.findResource that
verifies a URL by opening a connection and calling getInputStream().
The result of missing URLs for the root of nested jars and directories
is that classpath scanning that scans from the root (not a good idea
for performance reasons, but something that we should support) would
not find entries in /BOOT-INF/classes or in jars in /BOOT-INF/lib.
This commit updates our JarURLConnection so that it no longer throws
an IOException when asked for an InputStream for the root of a nested
entry (directory or jar).
Fixes gh-7003
This commit restores the logic in Handler that was changed when
d20ac56a was merged, while leaving the structural improvements intact.
In addition to a couple of changes where a typo meant the wrong
variable was being referenced, some logic branches now return false
rather than called super. This realigns our Handler's behaviour with
that of the JDK's.
Some more tests have also been added to try to catch the problems that
were introduced during the merge.
Closes gh-7021
Previously our handler didn't override parseURL or sameFile which
resulted in behaviour that differed from that of the JDK's handler.
Crucially, this would result in our JarURLConnection being passed
a spec that didn't contain a "!/". A knock-on effect of this was
that the connection would point to the root of the jar rather than
the intended entry.
Closes gh-7021
Previously, RandomAccessDataFile used a semaphore and acquired it
interruptibly. This meant that an interrupted thread was unable to
access the file. Notably, this would prevent LaunchedURLClassLoader from
loading classes or resources on an interrupted thread.
The previous commit (937f857) updates RandomAccessDataFile to acquire
the semaphore uninterruptibly. This commit adds a test to
LaunchedURLClassLoader to verify that it can now load a resource from
an interrupted thread.
Closes gh-6683
This commit improves the performance of JarURLConnection. There are two
main changes:
Firstly, the way in which the spec is determined has been changed so
that it’s no longer necessary to create an absolute file. Instead,
the JarFile’s pathFromRoot is used to extract the spec from the URL
relative to the JarFile.
Secondly, the number of temporary Objects that are created has been
reduced, for example by tracking an index as we process a String
rather than creating a new substring for each iteration.
See gh-6215
Previously, JarURLConnection assumed that that URL with which it was
created would contain the absolute path of the underlying jar file.
This meant that when it was created with a relative URL, it could fail
to find an entry or throw a StringIndexOutOfBoundsException.
This commit updates the logic for normalizing the input URL so that
both absolute and relative URLs are supported.
Closes gh-6109
Previously, JarURLConnection didn't override getPermission(). This
meant that it required all permissions. This was at odds with the
Oracle JVM's concrete sun.net.www.protocol.jar.JarURLConnection which
overrides getPermission to return a FilePermission with the read
action for the path of the underlying jar.
This commit updates our JarURLConnection to align its behaviour with
sun.net.www.protocol.jar.JarURLConnection.
Closes gh-5411
Update CentralDirectoryParser to reduce the number of objects created
when parsing the central directory. A single CentralDirectoryFileHeader
object is now reused as entries are parsed.
Fixes gh-5260
Previously, JarURLConnection would fail when created with a URL that
began with jar:file:// as the double-slash is not included in jarFile.getUrl().getFile().
This commit updates JarURLConnection to normalise the value return from
url.getFile() to remove a double-slash when present.
Fixes gh-5287
Closes gh-5289
Previously, if loader.path directly specified a jar file that contained
nested archives (.zip or .jar), launching would fail unless those
nested archives were uncompressed. However, if loader.path specified a
directory that contained such a jar file the launch would succeed. This
was because the nested archives within the jar were ignored.
This commit updates PropertiesLauncher so that its behaviour in the
scenarios described above is consistent by not looking for archives
nested with a jar that’s be specified on loader.path. The javadoc for
loader.path has also been updated to make it clear that loader.path
can points to directories or jar files, bringing it into line with
the reference guide.
Closes gh-3701
Previously, JarURLConnection would corrupt a URL that contained a
mixture of encoded and unencoded double-byte characters. URLs that
only contained unencoded double-byte characters were not affected as
they are passed through as-is.
This commit updates JarURLConnection.JarEntryName to correctly handle
characters with a value that won't fit in a single signed byte (a
value greater than 127). Such characters are now URL encoded and then
written to the output stream as multiple bytes.
Closes gh-5194
When an application is run as an executable archive with nested jars,
the application's own classes need to be able to load classes from
within the nested jars. This means that the application's classes need
to be loaded by the same class loader as is used for the nested jars.
When an application is launched with java -jar the contents of the
jar are on the class path of the app class loader, which is the
parent of the LaunchedURLClassLoader that is used to load classes
from within the nested jars. If the root of the jar includes the
application's classes, they would be loaded by the app class loader
and, therefore, would not be able to load classes from within the
nested jars.
Previously, this problem was resolved by LaunchedURLClassLoader being
created with a copy of all of the app class laoder's URLs and by
using an unconventional delegation model that caused it to skip its
parent (the app class loader) and jump straight to its root class
loader. This ensured that the LaunchedURLClassLoader would load both
the application's own classes and those from within any nested jars.
Unfortunately, this unusual delegation model has proved to be
problematic. We have seen and worked around some problems with Java
Agents (see gh-4911 and gh-863), but there are others (see gh-4868)
that cannot be made to work with the current delegation model.
This commit reworks LaunchedURLClassLoader to use a conventional
delegate model with the app class loader as its parent. With this
change in place, the application's own classes need to be hidden
from the app class loader via some other means. This is now achieved
by packaging application classes in BOOT-INF/classes (and, for
symmetry, nested jars are now packaged in BOOT-INF/lib). Both the
JarLauncher and the PropertiesLauncher (which supports the executable
jar layout) have been updated to look for classes and nested jars in
these new locations.
Closes gh-4897
Fixes gh-4868
Refactor `spring-boot-loader` to reduce the amount of memory required
to load fat & exploded jars. Jar files now no longer store a full list
of entry data records, but instead use an array of entry name hashes.
Since ClassLoaders often ask each JAR if they contain a particular
entry (and mostly they do not), the hash array provides a quick way to
deal with misses. Only when a hash does exist is data actually loaded
from the underlying file.
In addition to the JarFile changes, the Archive abstraction has also
been updated to reduce memory consumption.
See gh-4882
PropertiesLauncher creates a ClassLoader that is used by the Launcher
to load an application’s classes. During the creation of this
ClassLoader URLs from its ClassLoader. This resulted resulting in Java
agents that are added to the system class loader via the -javaagent
launch option being available on both the system class loader and the
created class loader. Java agents are intended to always be loaded by
the system class loader. Making them available on another class loader
breaks this model.
This is the same problem that was in ExecutableArchiveLauncher and
that was fixed in ee08667e (see gh-863).
This commit updates PropertiesLauncher so that it skips the URLs of
any Java agents (found by examining the JVM’s input arguments) when
copying URLs over to the new ClassLoader, thereby ensuring that Java
agents are only ever loaded by the system class loader.
Closes gh-4911
