For Java classes implemented in Go, it is useful to take a Java instance
and extract its wrapped Go instance. For example, consider the
java.lang.Runnable implementation wrapping a Go function:
package somepkg
type GoRunnable struct {
lang.Runnable
f func()
}
Java methods that take a java.lang.Runnable cannot directly take a
*GoRunnable, so this CL adds a Unwrap method:
import gorun "Java/somepkg/GoRunnable"
...
r := gorun.New()
r.Unwrap().(*GoRunnable).f = func() { ... }
javapkg.Run(r)
The extra interface conversion is unfortunately needed to avoid
import cycles.
Change-Id: Ib775a5712cd25aa75a19d364a55d76b1e11dce77
Reviewed-on: https://go-review.googlesource.com/35295
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Make the golang.org/x/mobile/bind/java buildable without CGO, and
replace the which tool with exec.LookPath. Both helps on Windows that
often don't have a C compiler available and no which command.
Found while testing external NDK use on Windows.
Change-Id: I6d3311aae3fa97acb61b5ab9bed334e4a608c386
Reviewed-on: https://go-review.googlesource.com/35174
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
The gomobile tool mishandled build tags in two ways, first by
ignoring tags for iOS, second by passing multiple tags along to
the go tool incorrectly. This CL fixes both.
Fixesgolang/go#18523Fixesgolang/go#18515
Change-Id: I28a49c1e23670adb085617d9f5fb5cd5e22a4b65
Reviewed-on: https://go-review.googlesource.com/34955
Reviewed-by: David Crawshaw <crawshaw@golang.org>
The Objective-C bindings was recently changed to support the empty
name prefix and to use that as the default. This CLs changed the Java
generators in the same way, supporting the empty Java package and using
it as the default.
Change-Id: I857affce686c67638a2b6c4e1da5d6a88d7ba560
Reviewed-on: https://go-review.googlesource.com/34778
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Before this CL, Java types that were only implicitly referenced
were represented as interface{}. However, if a value of such an
implicit type were passed to Java, a runtime crash would occur
because there would be no wrapper class to unwrap.
Fix this by generating implicit types, fixing the crashes,
gaining type safety, and removing the interface{} special case in
the generator.
While we're here, remove a redundant insert to the clsMap map in
java.go.
Change-Id: Ic50125da3d7cd6075899bf628d419b084c630490
Reviewed-on: https://go-review.googlesource.com/34777
Reviewed-by: David Crawshaw <crawshaw@golang.org>
The Go runtime doesn't handle SIGIPE signals from writing to closed
sockets or pipes in c-archive and c-shared mode (issue 17393).
Work around it in gomobile by simply ignoring all SIGPIPE signals;
they're not useful in mobile apps anyway.
Change-Id: Ibd7ee41058856c5eddb4a519345a3851a29e9b44
Reviewed-on: https://go-review.googlesource.com/33771
Reviewed-by: David Crawshaw <crawshaw@golang.org>
C compiler warnings are hidden in the gomobile build process. Expose
them through -Werror.
Change-Id: I2d87e5985f9ff874dc6feb836ba35c2bd848bfa6
Reviewed-on: https://go-review.googlesource.com/31517
Reviewed-by: David Crawshaw <crawshaw@golang.org>
The bind benchmarks are implemented as Go tests, but take quite a
while to run. Skip them in short mode.
Change-Id: I49ede84863b047aa8307bc0ef752fc7aa21e2d65
Reviewed-on: https://go-review.googlesource.com/31637
Reviewed-by: David Crawshaw <crawshaw@golang.org>
In Go type constructors can often return an error type too
beside an instance of the type being created. This is useful
in cases where the parameters might be wrong and instantiaion
cannot succeed. This CL extends the Java generator so that
these methods are also converted into class constructors that
also can throw.
Change-Id: I5e531eec126904a026767a8503968255b9fd833b
Reviewed-on: https://go-review.googlesource.com/31184
Reviewed-by: Elias Naur <elias.naur@gmail.com>
The go_seq_to_refnum function handles its argument object as a Java
object if it doesn't implement Seq.Proxy. Java classes implemented in
Go does not implement Seq.Proxy, but when passing "this" references to
Go, instances must be treated as a Go object.
Use go_seq_to_refnum_go everywhere "this" is passed to Go, which fixes
field accessors and simplifies the method call case.
Change-Id: I3d01c63d7b2081e6344ece431f5e5021a9dd7662
Reviewed-on: https://go-review.googlesource.com/31171
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Generate Cast functions that take a proxy for a Java class or interface,
and return a new proxy with the same reference. The Cast functions
panic if the underlying Java object is not an instance of the expected
type.
Change-Id: I08a5bf9a79139f0fac5dd102c7b028c8c989fc6d
Reviewed-on: https://go-review.googlesource.com/30095
Reviewed-by: David Crawshaw <crawshaw@golang.org>
A recent CL added Java constructors to generated classes that extends
or implements other Java classes and interfaces. Constructors for a
struct S are Go functions on the form
func NewS...(...) *S
If no such constructors exists, a default empty constructor is
generated.
Expand that to cover every exported Go struct.
Fixesgolang/go#17086
Change-Id: I910aba13d5884c3f67c946c62a8ac4a3db8e2ea7
Reviewed-on: https://go-review.googlesource.com/29710
Reviewed-by: David Crawshaw <crawshaw@golang.org>
CL 24800 changed the error representation from strings to objects.
However, since native errors types are not immediately compatible
across languages, wrapper types were introduced to bridge the gap.
This CL remove those wrappers and instead special case the error
proxy types to conform to their language error protocol.
Specifically:
- The ObjC proxy for Go errors now extends NSError and calls
initWithDomain to store the error message.
- The Go proxy for ObjC NSError return the localizedDescription
property for calls to Error.
- The Java proxy for Go errors ow extends Exception and
overrides getMessage() to return the error message.
- The Go proxy for Java Exceptions returns getMessage whenever
Error is called.
The end result is that error values behave more like normal objects
across the language boundary. In particular, instance identity is
now preserved: an error passed across the boundary and back will
result in the same instance.
There are two semantic changes that followed this change:
- The domain for wrapped Go errors is now always "go".
The domain wasn't useful before this CL: the domains were set to
the package name of function or method where the error happened
to cross the language boundary.
- If a Go method that returns an error is implemented in ObjC, the
implementation must now both return NO _and_ set the error result
for the calling Go code to receive a non-nil error.
Before this CL, because errors were always wrapped, a nil ObjC
could be represented with a non-nil wrapper.
Change-Id: Idb415b6b13ecf79ccceb60f675059942bfc48fec
Reviewed-on: https://go-review.googlesource.com/29298
Reviewed-by: David Crawshaw <crawshaw@golang.org>
The Java API wrapper generator use interface{} for Java classes
that no Go code references. Return values of unknown types are thrown
away, since they're effectively useless. Since the return values can
be used for nil checks and since casting of Java instances are
supported in CL 30095, this CL returns the naked *seq.Ref results
values instead.
Change-Id: I821b1c344a4c68c57fd34e2b655404e449de4c03
Reviewed-on: https://go-review.googlesource.com/30097
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Before, the Java generator let Java interfaces inherit java.lang.Object
methods. However, interfaces strictly doesn't inherit Object and since
the JNI GetMethodID returns NULL for Object methods on interface classes,
stop making Object a super class to interfaces.
Change-Id: I3757c1ed02c07ccffab74a30132d5197742c6513
Reviewed-on: https://go-review.googlesource.com/30096
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
Accept Java API interface types as arguments and return values from
bound Go package functions and methods. Also, allow Go structs
to extend Java classes and implement Java interfaces as well as override
and implement methods.
This is the third and final part of the implementation of the golang/go#16876
proposal.
Fixesgolang/go#16876
Change-Id: I6951dd87235553ce09abe5117a39a503466163c0
Reviewed-on: https://go-review.googlesource.com/28597
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Using the new Java class analyzer API, scan the bound packages
for references to Java classes and interfaces and generate Go
wrappers for them.
This is the second part of the implementation of proposal golang/go#16876.
For golang/go#16876
Change-Id: I59ec0ebdae0081a615dc34d450f344c20c03f871
Reviewed-on: https://go-review.googlesource.com/28596
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Errors was recently converted to use objects as representation instead
of strings. Issue golang/go#17073 exposed a few places that wasn't properly
updated. Fix them and add the test case from the the issue.
Fixesgolang/go#17073
Change-Id: I0191993a8427d930540716407fc09032f282fc66
Reviewed-on: https://go-review.googlesource.com/29176
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Before this CL, generated Java classes or interfaces were inner
classes to the top package class. That is both unnecessary and creates
ugly class names. Instead, move every generated class and interface to its
own package level class.
NOTE: This is a backwards incompatible change and requires every client
of gomobile APIs to be updated to leave out the package class in the
type names. For example, the Go type
package pkg
type S struct {
}
now generates (with the default java package name go) a Java class named
go.pkg.S. The name before this CL was go.pkg.Pkg.S.
Also, change the custom java package to specify the package prefix and
not the full package as before. This is an unfortunate change needed
to avoid name clashes between two bound packages. On the plus side,
the change brings the custom package case closer to the default behaviour,
which is a commen prefix, "go.", and a distinct java package for every
Go package bound.
Change-Id: Iadfaad56e101d1caf7e2a05006f4d384859a20fe
Reviewed-on: https://go-review.googlesource.com/27436
Reviewed-by: David Crawshaw <crawshaw@golang.org>
The change from using strings to objects for passing errors across
the language barrier broke the custom java package mode of gombile
bind. Fix it and add a runtime test to make sure it won't happen
again.
Fixesgolang/go#16262
Change-Id: Ia7f8afb79556798056f0755758052190081a2dbb
Reviewed-on: https://go-review.googlesource.com/24800
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
Add a missing #include to declare the exported Go function
setContext, and replace old GNU-style struct initializers.
Change-Id: Id1660559236c39505a47368a700c8e0ad834cf6c
Reviewed-on: https://go-review.googlesource.com/24491
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Gobind uses strings for passing errors across the language barrier.
However, since Gobind doesn't have a concept of a nil string, it
can't separate an empty native string from a nil string.
In turn, that means that empty errors, exceptions or NSError * with
an empty description are treated as no error. With ObjC, empty errors
are replaced with a default string to workaround the issue, while
with Java empty errors are silently ignored.
Fix this by replacing strings with actual error objects, wrapping
the Go error, Java Throwable or ObjC NSError *, and letting the
existing bind machinery take care of passing the references across.
It's a large change for a small corner case, but I believe objects
are a better fit for exception that strings. Error objects also
naturally leads to future additions, for example accessing the
exception class name or chained exception.
Change-Id: Ie03b47cafcb231ad1e12a80195693fa7459c6265
Reviewed-on: https://go-review.googlesource.com/24100
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Requiring user code to extend Go interface Stubs to be able to pass
Java objects to Go is clumsy and use up the single extend slot.
Instead, support (and enforce) java classes to implement translated
Go interface directly. This is similar to how ObjC works.
The stub classes are now gone, and users of gobind Java APIs need
to update their code to implement interfaces directly.
Change-Id: I880bb7c8e89d3c21210b2ab2c85ced8d7859ff48
Reviewed-on: https://go-review.googlesource.com/21313
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Each side of the language barrier maintains a map of reference numbers
to objects. Each entry has a reference count that exactly matches
the number of active proxy objects on the other side. When a reference
crosses the barrier, the count is incremented and when a proxy finalizer
is run, the count is decremented. If the count reaches 0, the reference
number and its object are removed from the map.
There is a possibility that a reference number is passed to the other
side, and the last proxy is then immediately garbage collected and
finalized. The reference counter then reaches 0 before the other side has
converted the reference number to its object, crashing the program.
This is possible in both Go/Java/ObjC but is most likely to happen in
ObjC because its own automatic reference count runtime frees objects
as soon as they are statically never referenced again.
Fix the race by always incrementing the reference count before sending
a reference across the barrier. When converting the reference back into
an object on the other side, decrement the counter again.
Only the new ObjC test fails without this fix, but I left the Java
counterpart in for good measure.
Change-Id: I92743aabec275b4a5b82b952052e7e284872ce02
Reviewed-on: https://go-review.googlesource.com/21311
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
Elias Naur
Péter SzilágyiandElias Naur