How to execute an AQL query with Java API? - java

I have a collection named docCollection and I want to perform a normal AQL query on for example:
FOR id IN docCollection FILTER id.center == "Germany" RETURN id
I have tried to use the example as stated here:
https://docs.arangodb.com/cookbook/JavaDriverXmlData.html
But it didn't worked for me and it showed me
Exception in thread "main" java.lang.NullPointerException

Normally you have to use driver.executeDocumentQuery(...) for document queries.
To illustrate the differences between driver.executeDocumentQuery(...) and driver.executeAqlQuery(...) I added an example.
Download the ArangoDB java driver on github and compile it with maven:
mvn clean install -DskipTests=true -Dgpg.skip=true -Dmaven.javadoc.skip=true -B
Maven creates the standalone driver JAR file (arangodb-java-driver-X.X.X-SNAPSHOT-standalone.jar) containing all dependencies in the target directory.
Fetch the example code:
wget https://gist.githubusercontent.com/anonymous/bd68b523647548e5fb36d27c29561cfe/raw/f2922d431b9f1e5a3f3239e9024cf342536f55f7/AqlExample.java
Compile the example code:
javac -classpath arangodb-java-driver-X.X.X-SNAPSHOT-standalone.jar AqlExample.java
Start the ArangoDB without authentication on the default port and run the example code:
java -classpath arangodb-java-driver-X.X.X-SNAPSHOT-standalone.jar:. AqlExample

Related

Quarkus Native Application with DioZero on Raspberry Pi using Docker containers (multi-arch)

Yoooo!
Scope
I am trying to deploy a Quarkus based application to a Raspberry Pi using some fancy technologies, my goal is to figure out an easy way to develop an application with Quarkus framework, subsequently deploy as native executable to a raspberry device with full GPIO pins access. Below I will provide you will see requirements that I set for myself and my environment settings to have a better picture of the problem that I faced.
Acceptance Criteria
Java 17
Build native executable using GraalVM
Execute native executable in a micro image on raspberry's docker
Target platform can vary
Be able to use GPIO, SPI, I2C and etc. interfaces of the raspberry
Environment
Development PC
Raspberry Pi Model 3 B+
os: Ubuntu 22.04.1 LTS
os: DietPy
platform: x86_64, linux/amd64
platform: aarch64, linux/arm64/v8
Prerequisites
Java: diozero a device I/O library
Docker: working with buildx
Quarkus: build a native executable
How I built ARM based Docker Images for Raspberry Pi using buildx CLI Plugin on Docker Desktop?
Building Multi-Architecture Docker Images With Buildx
Application
source code on github
As for project base I used getting-started application from
https://github.com/quarkusio/quarkus-quickstarts
Adding diozero library to pom.xml
<dependency>
<groupId>com.diozero</groupId>
<artifactId>diozero-core</artifactId>
<version>1.3.3</version>
</dependency>
Creating a simple resource to test GPIO pinspackage org.acme.getting.started;
import com.diozero.devices.LED;
import javax.ws.rs.Path;
import javax.ws.rs.QueryParam;
#Path("led")
public class LedResource {
#Path("on")
public String turnOn(final #QueryParam("gpio") Integer gpio) {
try (final LED led = new LED(gpio)) {
led.on();
} catch (final Throwable e) {
return e.getMessage();
}
return "turn on led on gpio " + gpio;
}
#Path("off")
public String turnOff(final #QueryParam("gpio") Integer gpio) {
try (final LED led = new LED(gpio)) {
led.off();
} catch (final Throwable e) {
return e.getMessage();
}
return "turn off led on gpio " + gpio;
}
}
4.Dockerfile
```
# Stage 1 : build with maven builder image with native capabilities
FROM quay.io/quarkus/ubi-quarkus-native-image:22.0.0-java17-arm64 AS build
COPY --chown=quarkus:quarkus mvnw /code/mvnw
COPY --chown=quarkus:quarkus .mvn /code/.mvn
COPY --chown=quarkus:quarkus pom.xml /code/
USER quarkus
WORKDIR /code
RUN ./mvnw -B org.apache.maven.plugins:maven-dependency-plugin:3.1.2:go-offline
COPY src /code/src
RUN ./mvnw package -Pnative
# Stage 2 : create the docker final image
FROM registry.access.redhat.com/ubi8/ubi-minimal:8.6-902
WORKDIR /work/
COPY --from=build /code/target/*-runner /work/application
# set up permissions for user 1001
RUN chmod 775 /work /work/application \
&& chown -R 1001 /work \
&& chmod -R "g+rwX" /work \
&& chown -R 1001:root /work
EXPOSE 8080
USER 1001
CMD ["./application", "-Dquarkus.http.host=0.0.0.0"]
```
Building image with native executable
Dockerfile based on quarkus docs, I changed image of the build container to quay.io/quarkus/ubi-quarkus-native-image:22.0.0-java17-arm64 and executor container to registry.access.redhat.com/ubi8/ubi-minimal:8.6-902, both of these are linux/arm64* compliant.
Since I am developing and building in linux/amd64 and I want to target linux/arm64/v8 my executable must be created in a target like environment. I can achieve that with buildx feature which enables cross-arch builds for docker images.
Installing QEMU
sudo apt-get install -y qemu-user-static
sudo apt-get install -y binfmt-support
Initializing buildx for linux/arm64/v8 builds
sudo docker buildx create --platform linux/arm64/v8 --name arm64-v8
Use new driver
sudo docker buildx use arm64-v8
Bootstrap driver
sudo docker buildx inspect --bootstrap
Verify
sudo docker buildx inspect
Name: arm64-v8
Driver: docker-container
Nodes:
Name: arm64-v80
Endpoint: unix:///var/run/docker.sock
Status: running
Platforms: linux/arm64*, linux/amd64, linux/amd64/v2, linux/amd64/v3, linux/riscv64, linux/ppc64le, linux/s390x, linux/386, linux/mips64le, linux/mips64, linux/arm/v7, linux/arm/v6
Now looks like we're ready to run the build. I ended up with the following command
sudo docker buildx build --push --progress plain --platform linux/arm64/v8 -f Dockerfile -t nanobreaker/agus:arm64 .
--push - since I need to deploy a final image somewhere
--platform linux/arm64/v8 - docker requires to define target platform
-t nanobreaker/agus:arm64 - my target repository for final image
It took ~16 minutes to complete the build and push the image
target platform is linux/arm64 as needed
59.75 MB image size, good enough already (with micro image I could achieve ~10 MB)
After I connected to raspberry, downloaded image and run it
docker run -p 8080:8080 nanobreaker/agus:arm64
Pretty nice, let's try to execute a http request to test out gpio pins
curl 192.168.0.20:8080/led/on?gpio=3
Okey, so I see here that there are permission problems and diozero library is not in java.library.path
We can fix permission problems by adding additional parameter to docker run command
docker run --privileged -p 8080:8080 nanobreaker/agus:arm64
PROBLEM
From this point I do not know how to resolve library load error in a native executable.
I've tried:
Pulled out native executable from final container, executed on raspberry host os and had same result, this makes me think that library was not included at GraalVM compile time?
Learning how library gets loaded https://github.com/mattjlewis/diozero/blob/main/diozero-core/src/main/java/com/diozero/util/LibraryLoader.java
UPDATE I
It looks like I have two options here
Figure out a way to create configuration for the diozero library so it is properly resolved by GraalVM during native image compilation.
Add library to the native image and pass it to the native executable.
UPDATE II
Further reading of quarkus docs landed me here https://quarkus.io/guides/writing-native-applications-tips
By default, when building a native executable, GraalVM will not include any of the resources that are on the classpath into the native executable it creates. Resources that are meant to be part of the native executable need to be configured explicitly. Quarkus automatically includes the resources present in META-INF/resources (the web resources) but, outside this directory, you are on your own.
I reached out #Matt Lewis (creator of diozero) and he was kind to share his configs, which he used to compile into GraalVM. Thank you Matt!
Here’s the documentation on my initial tests: https://www.diozero.com/performance/graalvm.html
I stashed the GraalVM config here: https://github.com/mattjlewis/diozero/tree/main/src/main/graalvm/config
So combining the knowledge we can enrich pom.xml with additional setting to tell GraalVM how to process our library
<quarkus.native.additional-build-args>
-H:ResourceConfigurationFiles=resource-config.json,
-H:ReflectionConfigurationFiles=reflection-config.json,
-H:JNIConfigurationFiles=jni-config.json,
-H:+TraceServiceLoaderFeature,
-H:+ReportExceptionStackTraces
</quarkus.native.additional-build-args>
Also added resource-config.json, reflection-config.json, jni-config.json to the resource folder of the project (src/main/resources)
First, I will try to create a native executable in my native os ./mvnw package -Dnative
Fatal error: org.graalvm.compiler.debug.GraalError: com.oracle.graal.pointsto.constraints.UnsupportedFeatureException: No instances of java.lang.ProcessHandleImpl are allowed in the image heap as this class should be initialized at image runtime. To see how this object got instantiated use --trace-object-instantiation=java.lang.ProcessHandleImpl.
Okey, so it failed, but let's trace object instantiation as recommended, maybe we can do something in configs to get around this. I added --trace-object-instantiation=java.lang.ProcessHandleImpl to the additional build args.
Fatal error: org.graalvm.compiler.debug.GraalError: com.oracle.graal.pointsto.constraints.UnsupportedFeatureException: No instances of java.lang.ProcessHandleImpl are allowed in the image heap as this class should be initialized at image runtime. Object has been initialized by the java.lang.ProcessHandleImpl class initializer with a trace:
at java.lang.ProcessHandleImpl.<init>(ProcessHandleImpl.java:227)
at java.lang.ProcessHandleImpl.<clinit>(ProcessHandleImpl.java:77)
. To fix the issue mark java.lang.ProcessHandleImpl for build-time initialization with --initialize-at-build-time=java.lang.ProcessHandleImpl or use the the information from the trace to find the culprit and --initialize-at-run-time=<culprit> to prevent its instantiation.
something new at least, let's try to initialize it first at build time with --initialize-at-build-time=java.lang.ProcessHandleImpl
Error: Incompatible change of initialization policy for java.lang.ProcessHandleImpl: trying to change BUILD_TIME from command line with 'java.lang.ProcessHandleImpl' to RERUN for JDK native code support via JNI
com.oracle.svm.core.util.UserError$UserException: Incompatible change of initialization policy for java.lang.ProcessHandleImpl: trying to change BUILD_TIME from command line with 'java.lang.ProcessHandleImpl' to RERUN for JDK native code support via JNI
Okey, we're not able to change the initialization kind and looks like it won't give us any effect.
I found out that with -H:+PrintClassInitialization we can generate a csv file with class initialization info
here we have two lines for java.lang.ProcessHandleImpl
java.lang.ProcessHandleImpl, RERUN, for JDK native code support via JNI
java.lang.ProcessHandleImpl$Info, RERUN, for JDK native code support via JNI
So it says that class is marked as RERUN, but isn't this the thing we're looking for? Makes no sense for me right now.
UPDATE III
With the configs for graalvm provided by #Matt I was able to compile a native image, but it fails anyways during runtime due to java.lang.UnsatisfiedLinkError, makes me feel like the library was not injected properly.
So looks like we just need to build a proper configuration file, in order to do this let's build our application without native for now, just run it on raspberry, trigger the code related to diozero, get output configs.
./mvnw clean package -Dquarkus.package.type=uber-jar
Deploying to raspberry, will run with graalvm agent for configs generation (https://www.graalvm.org/22.1/reference-manual/native-image/Agent/)
/$GRAALVM_HOME/bin/java -agentlib:native-image-agent=config-output-dir=config -jar ags-gateway-1.0.0-SNAPSHOT-runner.jar
Running simple requests to trigger diozero code (I've connected a led to raspberry on gpio 4, and was actually seeing it turn off/on)
curl -X POST 192.168.0.20:8080/blink/off?gpio=4
curl -X POST 192.168.0.20:8080/blink/on?gpio=4
I've published project with output configs
One thing I noticed that "pattern":"\\Qlib/linux-aarch64/libdiozero-system-utils.so\\E" aarch64 library gets pulled while running on py which is correct, but when I build on native OS I should specify 'amd64' platform.
Let's try to build a native with new configs
./mvnw package -Dnative
Successfully compiled, let's run and test
./target/ags-gateway-1.0.0-SNAPSHOT-runner
curl -X POST localhost:8080/led/on?gpio=4
And here we have error again
ERROR [io.qua.ver.htt.run.QuarkusErrorHandler] (executor-thread-0) HTTP Request to /led/on?gpio=4 failed, error id: b0ef3f8a-6813-4ea8-886f-83f626eea3b5-1: java.lang.UnsatisfiedLinkError: com.diozero.internal.provider.builtin.gpio.NativeGpioDevice.openChip(Ljava/lang/String;)Lcom/diozero/internal/provider/builtin/gpio/GpioChip; [symbol: Java_com_diozero_internal_provider_builtin_gpio_NativeGpioDevice_openChip or Java_com_diozero_internal_provider_builtin_gpio_NativeGpioDevice_openChip__Ljava_lang_String_2]
So I finally managed to build native image, but for some reason it didn't resolve JNI for native library.
Any thoughts on how to properly inject diozero library into native executable?
UPDATE IV
With help of #matthew-lewis we managed to build aarch64 native executable on amd64 os. I updated the source project with final configurations, but I must inform you that this is not a final solution and it doesn't cover all the library code, also according to the Matt's comments this might not be the only way to configure the graalvm build.
I've created a very simple Quarkus app that exposes a single REST API to list the available GPIOs. Note that it currently uses the mock provider that will be introduced in v1.3.4 so that I can test and run locally without deploying to a Raspberry Pi.
Running on a Pi would be as simple as removing the dependency to diozero-provider-mock in the pom.xml - you would also currently need to change the dependency to 1.3.3 until 1.3.4 is released.
Basically you need to add this to the application.properties file:
quarkus.native.additional-build-args=\
-H:ResourceConfigurationFiles=resource-config.json,\
-H:JNIConfigurationFiles=jni-config.json,\
-H:ReflectionConfigurationFiles=reflect-config.json
These files were generated by running com.diozero.sampleapps.LEDTest with the GraalVM Java executable (with a few minor tweaks), i.e.:
$GRAALVM_HOME/bin/java -agentlib:native-image-agent=config-output-dir=config \
-cp diozero-sampleapps-1.3.4.jar:diozero-core-1.3.4.jar:tinylog-api-2.4.1.jar:tinylog-impl-2.4.1.jar \
com.diozero.sampleapps.LEDTest 18
Note a lot of this was based my prior experiments with GraalVM as documented here and here.
The ProcessHandlerImpl error appear to be related to the tinylog reflect config that I have edited out.
Update 1
In making life easy for users of diozero, the library does a bit of static initialisation for things like detecting the local board. This causes issues when loading the most appropriate native library at most once (see LibraryLoader - you will notice it has a static Map of libraries that have been loaded which prevents it being loaded at runtime). To get around this I recommend adding this build property:
--initialize-at-run-time=com.diozero.sbc\\,com.diozero.util
Next, I have been unable to resolve the java.lang.ProcessHandleImpl issue, which prevents reenabling the service loader (diozero uses service loader quite a bit to enable flexibility and extensibility). It would be nice to be able to add this flag:
quarkus.native.auto-service-loader-registration=true
Instead I have specified relevant classes in resource-config.json.

Issue with Building Java Application in Docker

I am at the Java Directory. And When I execute the build command:
docker build -t karthikjohnbabu/hello-world-java:0.0.2.RELEASE .
I get the below error message. Please help me???
failed to solve with frontend dockerfile.v0: failed to create LLB definition: no match for platform in manifest sha256:195e9c227ad891282e80602cac2372a3085ecf4ceefbb395558ffe0f7bb0b9aa: not found.
Complete details of error below:
Try adding the following arg to the command:
--platform=linux/amd64
or alternatively use the following command to set an env var:
export DOCKER_DEFAULT_PLATFORM=linux/amd64
The information you gave leaves room for guessing.
I believe the important part is no match for platform in manifest.
Thus I believe in your dockerfile you start FROM someimage, and this someimage is not available for the platform you are using (which could mean MacOS).

Java: Class not found for PageRank algorithm in Apache Hadoop

I am trying to run PageRank algorithm in Apache Hadoop (2.6.5) cluster (1 master 2 slaves). I am using the program in this repository - https://github.com/danielepantaleone/hadoop-pagerank.git. I was able to compile all the sources using this command -
sudo javac -classpath ${HADOOP_CLASSPATH} -d ./build src/it/uniroma1/hadoop/pagerank/PageRank.java src/it/uniroma1/hadoop/pagerank/job1/PageRankJob1Mapper.java src/it/uniroma1/hadoop/pagerank/job1/PageRankJob1Reducer.java src/it/uniroma1/hadoop/pagerank/job2/PageRankJob2Mapper.java src/it/uniroma1/hadoop/pagerank/job2/PageRankJob2Reducer.java src/it/uniroma1/hadoop/pagerank/job3/PageRankJob3Mapper.java
I created the jar file using this command sudo jar -cf build/pagerank.jar build/.
I am trying to run the program just like the wordcount example like this -
sudo bin/hadoop jar hadoop-pagerank/build/pagerank.jar PageRank --
input /usr/local/hdfs/web-Google.txt --output /usr/local/hdfs-out-PR
Sometimes I get an error like this -
Exception in thread "main" java.lang.NoClassDefFoundError: PageRank (wrong name: it/uniroma1/hadoop
/pagerank/PageRank)
and sometimes I get an error like this - Exception in thread "main" java.lang.ClassNotFoundException: PageRank for different types of compilation.
I am not sure what am I doing wrong. Can anyone please help me in proper steps to compile and run the program in Hadoop ? I dont have any pom.xml file and I am able to run the provided wordcount example jar.
You have to use package name before the name of the class,
it means you have to use :
it.uniroma1.hadoop.pagerank.PageRank
rather than PageRank
in your command.
like this :
hadoop jar hadoop-pagerank/build/pagerank.jar it.uniroma1.hadoop.pagerank.PageRank --input /usr/local/hdfs/web-Google.txt --output /usr/local/hdfs-out-PR

Not able to use schemacrawler.

I have followed this link, http://schemacrawler.sourceforge.net/bundled.html
I am using Oracle 11g database,
As per the doc I have downloaded the bundle for Oracle and downloaded the ojdbc driver for it (ojdbc.6.jar) and placed it in the lib folder,
then fired the command:-
-host=xxx -port=xxx -database=xxx -user=xxx -password=xxx
But its not working.
For unix its throwing error:-
-bash: -host=xxx: command not found
When I fire the command:-
java -classpath lib/*:. schemacrawler.tools.oracle.Main $* -host=xxx -port=xxx -database=xxx -user=xxx -password=xxx
It throws the error:-
schemacrawler.schemacrawler.SchemaCrawlerException: No command specified
at schemacrawler.tools.commandline.SchemaCrawlerCommandLine.<init>(SchemaCrawlerCommandLine.java:88)
at schemacrawler.tools.commandline.SchemaCrawlerCommandLine.<init>(SchemaCrawlerCommandLine.java:62)
at schemacrawler.tools.commandline.SchemaCrawlerMain.main(SchemaCrawlerMain.java:76)
at schemacrawler.tools.oracle.Main.main(Main.java:44)
Please help to resolve
To get help on how to use SchemaCrawler for Oracle, please use the following command:
java -classpath lib/*:. schemacrawler.tools.oracle.Main
Sualeh Fatehi, SchemaCrawler

tdbloader on Cygwin: Gettging FileNotFoundException: d:\cygdrive\d\....\node2id.idn

I am completely new to Jena/TDB. All I want to do is to load data from some sample rdf, N3 etc file using tdb scripts or through java api.
I am tried to use tbdloader on Cygwin to load data (tdb-0.9.0, on Windows XP with IBM Java 1.6). Following are the command that I ran:
$ export TDBROOT=/cygdrive/d/Project/Store_DB/jena-tdb-0.9.0-incubating
$ export PATH=$TDBROOT/bin:$PATH
I also changed classpath for java in the tdbloader script as mentioned at tdbloader on Cygwin: java.lang.NoClassDefFoundError :
exec java $JVM_ARGS $SOCKS -cp "PATH_OF_JAR_FILES" "tdb.$TDB_CMD" $TDB_SPEC "$#"
So when I run $ tdbloader --help it shows the help correctly.
But when I run
$ tdbloader --loc /cygdrive/d/Project/Store_DB/data1
OR
$ tdbloader --loc /cygdrive/d/Project/Store_DB/data1 test.rdf
I am getting following exception:
com.hp.hpl.jena.tdb.base.file.FileException: Failed to open: d:\cygdrive\d\Project\Store_DB\data1\node2id.idn (mode=rw)
at com.hp.hpl.jena.tdb.base.file.ChannelManager.open$(ChannelManager.java:83)
at com.hp.hpl.jena.tdb.base.file.ChannelManager.openref$(ChannelManager.java:58)
at com.hp.hpl.jena.tdb.base.file.ChannelManager.acquire(ChannelManager.java:47)
at com.hp.hpl.jena.tdb.base.file.FileBase.<init>(FileBase.java:57)
at com.hp.hpl.jena.tdb.base.file.FileBase.<init>(FileBase.java:46)
at com.hp.hpl.jena.tdb.base.file.FileBase.create(FileBase.java:41)
at com.hp.hpl.jena.tdb.base.file.BlockAccessBase.<init>(BlockAccessBase.java:46)
at com.hp.hpl.jena.tdb.base.block.BlockMgrFactory.createStdFile(BlockMgrFactory.java:98)
at com.hp.hpl.jena.tdb.base.block.BlockMgrFactory.createFile(BlockMgrFactory.java:82)
at com.hp.hpl.jena.tdb.base.block.BlockMgrFactory.create(BlockMgrFactory.java:58)
at com.hp.hpl.jena.tdb.setup.Builder$BlockMgrBuilderStd.buildBlockMgr(Builder.java:196)
at com.hp.hpl.jena.tdb.setup.Builder$RangeIndexBuilderStd.createBPTree(Builder.java:165)
at com.hp.hpl.jena.tdb.setup.Builder$RangeIndexBuilderStd.buildRangeIndex(Builder.java:134)
at com.hp.hpl.jena.tdb.setup.Builder$IndexBuilderStd.buildIndex(Builder.java:112)
at com.hp.hpl.jena.tdb.setup.Builder$NodeTableBuilderStd.buildNodeTable(Builder.java:85)
at com.hp.hpl.jena.tdb.setup.DatasetBuilderStd$NodeTableBuilderRecorder.buildNodeTable(DatasetBuilderStd.java:389)
at com.hp.hpl.jena.tdb.setup.DatasetBuilderStd.makeNodeTable(DatasetBuilderStd.java:300)
at com.hp.hpl.jena.tdb.setup.DatasetBuilderStd._build(DatasetBuilderStd.java:167)
at com.hp.hpl.jena.tdb.setup.DatasetBuilderStd.build(DatasetBuilderStd.java:157)
at com.hp.hpl.jena.tdb.setup.DatasetBuilderStd.build(DatasetBuilderStd.java:70)
at com.hp.hpl.jena.tdb.StoreConnection.make(StoreConnection.java:132)
at com.hp.hpl.jena.tdb.transaction.DatasetGraphTransaction.<init>(DatasetGraphTransaction.java:46)
at com.hp.hpl.jena.tdb.sys.TDBMakerTxn._create(TDBMakerTxn.java:50)
at com.hp.hpl.jena.tdb.sys.TDBMakerTxn.createDatasetGraph(TDBMakerTxn.java:38)
at com.hp.hpl.jena.tdb.TDBFactory._createDatasetGraph(TDBFactory.java:166)
at com.hp.hpl.jena.tdb.TDBFactory.createDatasetGraph(TDBFactory.java:74)
at com.hp.hpl.jena.tdb.TDBFactory.createDataset(TDBFactory.java:53)
at tdb.cmdline.ModTDBDataset.createDataset(ModTDBDataset.java:95)
at arq.cmdline.ModDataset.getDataset(ModDataset.java:34)
at tdb.cmdline.CmdTDB.getDataset(CmdTDB.java:137)
at tdb.cmdline.CmdTDB.getDatasetGraph(CmdTDB.java:126)
at tdb.cmdline.CmdTDB.getDatasetGraphTDB(CmdTDB.java:131)
at tdb.tdbloader.loadQuads(tdbloader.java:163)
at tdb.tdbloader.exec(tdbloader.java:122)
at arq.cmdline.CmdMain.mainMethod(CmdMain.java:97)
at arq.cmdline.CmdMain.mainRun(CmdMain.java:59)
at arq.cmdline.CmdMain.mainRun(CmdMain.java:46)
at tdb.tdbloader.main(tdbloader.java:53)
Caused by: java.io.FileNotFoundException: d:\cygdrive\d\Project\Store_DB\data1\node2id.idn (The system cannot find the path specified.)
at java.io.RandomAccessFile.open(Native Method)
at java.io.RandomAccessFile.<init>(RandomAccessFile.java:222)
at java.io.RandomAccessFile.<init>(RandomAccessFile.java:107)
at com.hp.hpl.jena.tdb.base.file.ChannelManager.open$(ChannelManager.java:80)
... 37 more
I am not sure what node2id.idn file is and why is it expecting it?
The file node2id.idn is one of TDB's internal index files. It's not something that you have to create or manage for yourself. I've just tried tdbloader on cygwin myself, it it worked OK for me. I can think of two basic possibilities:
your disk is full
the TDB index is corrupted
If this is the first file you are loading into an otherwise emtpy TDB, the second possibility is unlikely. If you are loading into a non-empty TDB, try deleting the TDB image and starting again. Note that TDB by itself does not manage concurrent writes: if you have more than one process writing to a single TDB image, you must handle locking at the application level, or use TDB's transactions.
The final possibility, of course, is that your disk is flaky. You might want to try your code on another machine.
If none of these suggestions help, please send a complete minimal test case to the Jena users list.

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