Uri uri = data.getData(); //I'm getting this in onActivityResult. The path is correct; this code hasn't changed between REST libraries and it's worked before
parameterPairsMap.put(fileName, new File(URI.create(uri.toString())));

MultipartTypedOutput multipartTypedOutput = new MultipartTypedOutput();
for(Map.Entry<String, Object> entry : pairs.entrySet()){
if(entry.getValue() instanceof File){
    multipartTypedOutput.addPart(entry.getKey(), new TypedFile("*/*", (File)entry.getValue()));
}
else{
    multipartTypedOutput.addPart(entry.getKey(), new TypedString(entry.getValue().toString()));
}
}

restAdapter.create(RetrofitInterface.class).buildWithParameters(buildName, multipartTypedOutput, callbacks);

@POST("/job/{buildName}/buildWithParameters")
void buildWithParameters(@Path("buildName") String buildName, @Body MultipartTypedOutput typedOutput, Callback<String> callbacks);

@Multipart
@POST("/job/{buildName}/buildWithParameters")
void buildWithParameters(@Path("buildName") String buildName, @Part("") MultipartTypedOutput typedOutput, Callback<String> callbacks);

W/System.err﹕ retrofit.RetrofitError: java.io.IOException: unexpected end of stream
W/System.err﹕ at retrofit.RestAdapter$RestHandler.invokeRequest(RestAdapter.java:421)
W/System.err﹕ at retrofit.RestAdapter$RestHandler.access$100(RestAdapter.java:264)
W/System.err﹕ at retrofit.RestAdapter$RestHandler$2.obtainResponse(RestAdapter.java:315)
W/System.err﹕ at retrofit.CallbackRunnable.run(CallbackRunnable.java:42)
W/System.err﹕ at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
W/System.err﹕ at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
W/System.err﹕ at retrofit.Platform$Android$2$1.run(Platform.java:142)
W/System.err﹕ at java.lang.Thread.run(Thread.java:841)
W/System.err﹕ Caused by: java.io.IOException: unexpected end of stream
W/System.err﹕ at libcore.net.http.FixedLengthOutputStream.close(FixedLengthOutputStream.java:58)
W/System.err﹕ at libcore.net.http.HttpEngine.readResponse(HttpEngine.java:818)
W/System.err﹕ at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:283)
W/System.err﹕ at libcore.net.http.HttpURLConnectionImpl.getResponseCode(HttpURLConnectionImpl.java:497)
W/System.err﹕ at retrofit.client.UrlConnectionClient.readResponse(UrlConnectionClient.java:71)
W/System.err﹕ at retrofit.client.UrlConnectionClient.execute(UrlConnectionClient.java:38)
W/System.err﹕ at retrofit.RestAdapter$RestHandler.invokeRequest(RestAdapter.java:358)
W/System.err﹕ ... 7 more

D/Retrofit﹕ ---> HTTP POST /*edited*/
D/Retrofit﹕ Authorization: Basic /*edited*/
D/Retrofit﹕ Content-Type: multipart/form-data; boundary=5f8e6431-ed42-4d8b-95ce-d749f1797f04
D/Retrofit﹕ Content-Length: 1090
D/Retrofit﹕ --5f8e6431-ed42-4d8b-95ce-d749f1797f04
    Content-Disposition: form-data; name="branch"
    Content-Type: text/plain; charset=UTF-8
    Content-Length: 18
    Content-Transfer-Encoding: binary
    testingOneTwoTHree
    --5f8e6431-ed42-4d8b-95ce-d749f1797f04
    Content-Disposition: form-data; name="one.properties"; filename="local.properties"
    Content-Type: */*
    Content-Length: 449
    Content-Transfer-Encoding: binary
    ## This file is automatically generated by Android Studio.
    # Do not modify this file -- YOUR CHANGES WILL BE ERASED!
    #
    # This file should *NOT* be checked into Version Control Systems,
    # as it contains information specific to your local configuration.
    #
    # Location of the SDK. This is only used by Gradle.
    # For customization when using a Version Control System, please read the
    # header note.
    sdk.dir=/Users/gimmiepepsi/Downloads/android-sdk-macosx
    --5f8e6431-ed42-4d8b-95ce-d749f1797f04
    Content-Disposition: form-data; name="isBoolean"
    Content-Type: text/plain; charset=UTF-8
    Content-Length: 4
    Content-Transfer-Encoding: binary
    true
    --5f8e6431-ed42-4d8b-95ce-d749f1797f04--
D/Retrofit﹕ ---> END HTTP (1090-byte body)
D/Retrofit﹕ ---- ERROR /* edited */
D/Retrofit﹕ java.io.IOException: unexpected end of stream
            at libcore.net.http.FixedLengthOutputStream.close(FixedLengthOutputStream.java:58)
            at libcore.net.http.HttpEngine.readResponse(HttpEngine.java:818)
            at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:283)
            at libcore.net.http.HttpURLConnectionImpl.getResponseCode(HttpURLConnectionImpl.java:497)
            at retrofit.client.UrlConnectionClient.readResponse(UrlConnectionClient.java:71)
            at retrofit.client.UrlConnectionClient.execute(UrlConnectionClient.java:38)
            at retrofit.RestAdapter$RestHandler.invokeRequest(RestAdapter.java:358)
            at retrofit.RestAdapter$RestHandler.access$100(RestAdapter.java:264)
            at retrofit.RestAdapter$RestHandler$2.obtainResponse(RestAdapter.java:315)
            at retrofit.CallbackRunnable.run(CallbackRunnable.java:42)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
            at retrofit.Platform$Android$2$1.run(Platform.java:142)
            at java.lang.Thread.run(Thread.java:841)
D/Retrofit﹕ ---- END ERROR

W/System.err﹕ retrofit.RetrofitError: java.io.IOException: unexpected end of stream
W/System.err﹕ at retrofit.RestAdapter$RestHandler.invokeRequest(RestAdapter.java:421)
W/System.err﹕ at retrofit.RestAdapter$RestHandler.access$100(RestAdapter.java:264)
W/System.err﹕ at retrofit.RestAdapter$RestHandler$2.obtainResponse(RestAdapter.java:315)
W/System.err﹕ at retrofit.CallbackRunnable.run(CallbackRunnable.java:42)
W/System.err﹕ at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
W/System.err﹕ at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
W/System.err﹕ at retrofit.Platform$Android$2$1.run(Platform.java:142)
W/System.err﹕ at java.lang.Thread.run(Thread.java:841)
W/System.err﹕ Caused by: java.io.IOException: unexpected end of stream
W/System.err﹕ at libcore.net.http.FixedLengthOutputStream.close(FixedLengthOutputStream.java:58)
W/System.err﹕ at libcore.net.http.HttpEngine.readResponse(HttpEngine.java:818)
W/System.err﹕ at libcore.net.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:283)
W/System.err﹕ at libcore.net.http.HttpURLConnectionImpl.getResponseCode(HttpURLConnectionImpl.java:497)
W/System.err﹕ at retrofit.client.UrlConnectionClient.readResponse(UrlConnectionClient.java:71)
W/System.err﹕ at retrofit.client.UrlConnectionClient.execute(UrlConnectionClient.java:38)
W/System.err﹕ at retrofit.RestAdapter$RestHandler.invokeRequest(RestAdapter.java:358)
W/System.err﹕ ... 7 more