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Is there any way to automatically setting windows path in a string in groovy?

My project root directory is:
D:/Project/Node_Project
I am using a gradle plugin to install nodejs temporarily in my project root directory so that some nodejs command can run in the project while the thoject builds. The plugin is as below:
plugins {
id "com.github.node-gradle.node" version "2.2.4"
}
node {
download = true
version = "10.10.0"
distBaseUrl = 'https://nodejs.org/dist'
workDir = file("${project.buildDir}/nodejs")
}
So, nodejs is getting installed inside the project in the location:
D:/Project/Node_Project/build/nodejs/node-v10.10.0-win-x64
Now, I am using a .execute(String[] "path to set at environment variable", String path of file to be executed which is in the project root directory) method to run a windows command with node dependency. Code below:
cmd = "node connect.js"
def process = cmd.execute(["PATH=${project.projectDir}/build/nodejs/node-v10.10.0-win-x64"],null)
In the above .execute method, is there a way to auto-populate the "build/nodejs/node-v10.10.0-win-x64" part of the string instead of hardcoding it into the method?
Something like:
def process = cmd.execute(["PATH=${project.projectDir}/.*"],null)
Syntax of .execute method:
https://docs.groovy-lang.org/latest/html/groovy-jdk/java/lang/String.html#execute(java.lang.String[],%20java.io.File)
All the codes are inside "build.gradle" file. Please help!

I asked why you don't just write a task of type NodeTask, but I understand that you like to run a it in the background, which you can't do with that.
You could list the content of a directory and use that as part of the command. But you could also just grab it from the extension provided by the plugin.
This is not documented and it might break in future releases of the plugin, but you can do something like this (Groovy DSL):
task connectJS {
dependsOn nodeSetup
doFirst {
def connectProcess = "$node.variant.nodeExec $projectDir/src/js/connect.js".execute()
// Blocking readers (if async, pipe to a log file instead)
connectProcess.in.eachLine { logger.info(it) }
connectProcess.err.eachLine { logger.err(it) }
}
}

Google OR-Tools in Intellij: UnsatisfiedLinkError

I am setting up a java framework that should use the Google OR-Tools. The code below compiles successfully, but throws an exception at runtime:
Exception in thread "main" java.lang.UnsatisfiedLinkError: com.google.ortools.linearsolver.operations_research_linear_solverJNI.MPSolver_CLP_LINEAR_PROGRAMMING_get()I
at com.google.ortools.linearsolver.operations_research_linear_solverJNI.MPSolver_CLP_LINEAR_PROGRAMMING_get(Native Method)
at com.google.ortools.linearsolver.MPSolver$OptimizationProblemType.<clinit>(MPSolver.java:221)
at Main.main(Main.java:15)
I am using Intellij 2018.3 on Windows 10. I spent a lot of time trying to get this run, but unsuccessful. Based on what I found on the internet, the exception might be caused by poor linking and/or missing external libraries on which OR-Tools depends. However, I don't have the background to resolve this issue, and also Intellij does not highlight anything. Any idea what the problem is?
For completion, this is the code I run:
import com.google.ortools.linearsolver.MPObjective;
import com.google.ortools.linearsolver.MPSolver;
import com.google.ortools.linearsolver.MPVariable;
public final class Main {
public static void main(String[] args) {
// Create the linear solver with the GLOP backend.
MPSolver solver =
new MPSolver("SimpleLpProgram", MPSolver.OptimizationProblemType.GLOP_LINEAR_PROGRAMMING);
// Create the variables x and y.
MPVariable x = solver.makeNumVar(0.0, 1.0, "x");
MPVariable y = solver.makeNumVar(0.0, 2.0, "y");
System.out.println("Number of variables = " + solver.numVariables());
// Create a linear constraint, 0 <= x + y <= 2.
MPConstraint ct = solver.makeConstraint(0.0, 2.0, "ct");
ct.setCoefficient(x, 1);
ct.setCoefficient(y, 1);
System.out.println("Number of constraints = " + solver.numConstraints());
// Create the objective function, 3 * x + y.
MPObjective objective = solver.objective();
objective.setCoefficient(x, 3);
objective.setCoefficient(y, 1);
objective.setMaximization();
solver.solve();
System.out.println("Solution:");
System.out.println("Objective value = " + objective.value());
System.out.println("x = " + x.solutionValue());
System.out.println("y = " + y.solutionValue());
}
}

In my case solution was simple - I just needed to add this singe line of code:
Loader.loadNativeLibraries();
where loader comes from com.google.ortools.Loader

Disclaimer: more a long comment than an answer...
note: I supposed you are using the github repository of or-tools if you used the binary package it should be more or less the same...
1) You must load the jni library which will load the OR-Tools C++ libraries and its dependencies...
/** Simple linear programming example.*/
public class Main {
static {
System.loadLibrary("jniortools");
}
public static void main(String[] args) throws Exception {
2) Did you manage to run the java samples ?
make run SOURCE=ortools/linear_solver/samples/SimpleLpProgram.java
ref: https://developers.google.com/optimization/introduction/java#simple_example
3) As Kayaman pointed out, you must pass the folder where the java runtime can find the native libraries (i.e. the JNI wrapper jniortools.dll and its dependencies libortools.dll)
if you look at the console log you'll see the full command line:
java -Xss2048k -Djava.library.path=lib -cp lib\sample.jar;lib\com.google.ortools.jar;lib\protobuf.jar ...\sample
Which comes from, the makefiles/Makefile.java file:
JAVAFLAGS = -Djava.library.path=$(LIB_DIR)
...
ifeq ($(SOURCE_SUFFIX),.java) # Those rules will be used if SOURCE contain a .java file
$(CLASS_DIR)/$(SOURCE_NAME): $(SOURCE) $(JAVA_OR_TOOLS_LIBS) | $(CLASS_DIR)
-$(DELREC) $(CLASS_DIR)$S$(SOURCE_NAME)
-$(MKDIR_P) $(CLASS_DIR)$S$(SOURCE_NAME)
"$(JAVAC_BIN)" -d $(CLASS_DIR)$S$(SOURCE_NAME) \
-cp $(LIB_DIR)$Scom.google.ortools.jar$(CPSEP)$(LIB_DIR)$Sprotobuf.jar \
$(SOURCE_PATH)
...
.PHONY: run # Run a Java program.
run: build
"$(JAVA_BIN)" -Xss2048k $(JAVAFLAGS) \
-cp $(LIB_DIR)$S$(SOURCE_NAME)$J$(CPSEP)$(LIB_DIR)$Scom.google.ortools.jar$(CPSEP)$(LIB_DIR)$Sprotobuf.jar \
$(SOURCE_NAME) $(ARGS)
endif
src: https://github.com/google/or-tools/blob/46173008fdb15dae1dca0e8fa42a21ed6190b6e4/makefiles/Makefile.java.mk#L15
and
https://github.com/google/or-tools/blob/46173008fdb15dae1dca0e8fa42a21ed6190b6e4/makefiles/Makefile.java.mk#L328-L333
note: you can run make detect_java to know the flags i.e. value of LIB_DIR
note: if you did use the precompiled package the Makefile is here:
https://github.com/google/or-tools/blob/stable/tools/Makefile.cc.java.dotnet
Then after you can try to add this option in Intellij...
You must understand that or-tools is a set of C++ native libraries which are wrapped to Java using the SWIG generator.

To make it work using Intellij (over a windows machine) you need to:
Install Microsoft Visual C++ Redistributable for Visual Studio
Download and extract the OR-Tools library for Java
In intellij, add jar dependency to the 2 jars under the lib folder of the extracted files (each of the 2 jars separately, do not add to lib folder itself. This is why).
Add the lib library path to VM options. In Intellij edit your run-configuration and add to vm options: -Djava.library.path=<path to the lib folder that hold the jars>
Load the jni library statically by adding the below code to your class (as mentioned here.)
static {
System.loadLibrary("jniortools");
}

Include multiple source directories in Qt for Android

I want to include Java source code from multiple directories (which are shared between projects) in a Qt for Android project. On http://imaginativethinking.ca/what-the-heck-how-do-i-share-java-code-between-qt-android-projects/ an approach is described which copies the Java source files:
# This line makes sure my custom manifest file and project specific java code is copied to the android-build folder
ANDROID_PACKAGE_SOURCE_DIR = $$PWD/android
# This is a custom variable which holds the path to my common Java code
# I use the $$system_path() qMake function to make sure that my directory separators are correct for the platform I'm compiling on as you need to use the correct separator in the Make file (i.e. \ for Windows and / for Linux)
commonAndroidFilesPath = $$system_path( $$PWD/../CommonLib/android-sources/src )
# This is a custom variable which holds the path to the src folder in the output directory. That is where they need to go for the ANT script to compile them.
androidBuildOutputDir = $$system_path( $$OUT_PWD/../android-build/src )
# Here is the magic, this is the actual copy command I want to run.
# Make has a platform agnostic copy command macro you can use which substitutes the correct copy command for the platform you are on: $(COPY_DIR)
copyCommonJavaFiles.commands = $(COPY_DIR) $${commonAndroidFilesPath} $${androidBuildOutputDir}
# I tack it on to the 'first' target which exists by default just because I know this will happen before the ANT script gets run.
first.depends = $(first) copyCommonJavaFiles
export(first.depends)
export(copyCommonJavaFiles.commands)
QMAKE_EXTRA_TARGETS += first copyCommonJavaFiles
With later Qt versions the code has to be changed to this:
commonAndroidFilesPath = $$system_path($$PWD/android/src)
androidBuildOutputDir = $$system_path($$OUT_PWD/../android-build)
createCommonJavaFilesDir.commands = $(MKDIR) $${androidBuildOutputDir}
copyCommonJavaFiles.commands = $(COPY_DIR) $${commonAndroidFilesPath} $${androidBuildOutputDir}
first.depends = $(first) createCommonJavaFilesDir copyCommonJavaFiles
export(first.depends)
export(createCommonJavaFilesDir.commands)
export(copyCommonJavaFiles.commands)
QMAKE_EXTRA_TARGETS += first createCommonJavaFilesDir copyCommonJavaFiles
Is this the standard way to go, or is there some built-in functionality for including multiple Java source directories in Qt for Android projects?
Regards,

A much cleaner solution is this one:
CONFIG += file_copies
COPIES += commonJavaFilesCopy
commonJavaFilesCopy.files = $$files($$system_path($$PWD/android/src))
commonJavaFilesCopy.path = $$OUT_PWD/android-build

How to set up classpath of JavaCompiler to multiple .jar files using wildcard

I am using JavaCompiler of javax.tools to compile some java code and I am trying to use wildcard in my classpath in order to include all the .jar files but I fail.
Here is my code:
String classpath = "C:\tomcat6\webapps\myapp/WEB-INF/lib/javax.ws.rs-api-2.0-m10.jar;"
+ "C:\\tomcat6\\webapps\\myapp/WEB-INF/lib/javax.persistence-2.1.0.jar";
Iterable<String> options = Arrays.asList("-d", classesBaseDir,
"-classpath", classpath);
JavaCompiler.CompilationTask task = compiler.getTask(null, fileManager,
diagnostics, options, null, file);
boolean result = task.call();
The code above works just fine. But when I am trying to change the classpath to
String classpath = "C:\\tomcat6\\webapps\\myapp/WEB-INF/lib/*";
it fails with
compiler.err.doesnt.exist|package javax.ws.rs does not exist
...
symbol: class GET
location: class com.my.oasis.resources.TestClass
09/04/2014 14:27:09:030 | COMPILER_DIAGNOSTIC | compileResource() - compiler.err.cant.resolve.location|cannot find symbol
...
I have also tried the following alterations
String classpath = "\"C:\\tomcat6\\webapps\\myapp/WEB-INF/lib/*\"";
String classpath = "'C:\\tomcat6\\webapps\\myapp/WEB-INF/lib/*'";
but none of them worked. Any ideas?
Thanks
Note: the reason why the path includes slashes and backslashes is because the my program identifies the environment in runtime and auto completes the path.
Edit: I am using tomcat 6 and java 1.7.0_21

Wildcards: Since Java 1.6 wildcards are supported when using java/javaw/javac, more information: Windows/Solaris and Linux
example:
javac -cp "lib/*" Test.java
This uses all .jar files (not .class!) in the lib directory as classpath. This should not be confused with the *-expansion of your shell. -cp lib/* gets expanded to -cp lib/a.jar lib/b.jar which is not valid argument syntax. In order to avoid this you have to add quotation marks: -cp "lib/*"
The cause of your Problem: You are trying to call the Java compiler from source directly with its Java API. This source code does not contain the wildcard expansion.
The JDK ships with a wrapper binary (javac,javadoc,javah,javap are all the same binary) which does some things and finally calls the compiler task. This wrapper also expands the wildcards in your classpath and therefore the compiler task doesn't have to do this anymore (and it doesn't). See at Compiler Readme section "build -> Notes -> The launcher". Launcher sourcecode.
Solution:
A very poor solution would be to call javac through a Processbuilder. (This is not recommended since it is a complicated and error prone solution for a simple problem)
Expand the wildcards yourself:
example code:
String classpath = buildClassPath("lib/", "test/", "lib/*");
System.out.println(classpath);
// output: lib/;test/;lib/a.jar;lib/b.jar;
This function takes all classpath entries and builds one classpath. Classpath entries with a wildcard in it will get expanded.
/**
* This function builds a classpath from the passed Strings
*
* #param paths classpath elements
* #return returns the complete classpath with wildcards expanded
*/
private static String buildClassPath(String... paths) {
StringBuilder sb = new StringBuilder();
for (String path : paths) {
if (path.endsWith("*")) {
path = path.substring(0, path.length() - 1);
File pathFile = new File(path);
for (File file : pathFile.listFiles()) {
if (file.isFile() && file.getName().endsWith(".jar")) {
sb.append(path);
sb.append(file.getName());
sb.append(System.getProperty("path.separator"));
}
}
} else {
sb.append(path);
sb.append(System.getProperty("path.separator"));
}
}
return sb.toString();
}

Using backslashes or slashes makes no difference. But you obviously assume that the path is auto-globbed (like a normal command line would). This does not happen. So you run your compiler as you would with a command line arg of
-classpath 'C:\\tomcat6\\webapps\\myapp/WEB-INF/lib/*'
which is not what you want. You may look into the API docs for java.io.File.listFiles(FileFilter) or even java.nio.file.Files.walkFileTree(Path, FileVisitor) to gain a better understanding.
To expand a bit on that, when your shell sees C:\tomcat6\webapps\myapp/WEB-INF/lib/* it expands it into a space-separated list of whatever is in your WEB-INF/lib directory. This is called globbing, or since it's done automatically, auto-globbing.
Now Java doesn't do that, but you can build it yourself in a few lines of code:
StringBuilder sb = new StringBuilder();
String[] filenames = new File("C:\\tomcat6\\webapps\\myapp/WEB-INF/lib/").list();
for(int i = 0; i < filenames.length; i++) {
if(i > 0) sb.append(File.pathSeparatorChar); // separate with ':' or ';' on Win
sb.append(filenames[i]); // append the filename
}
Iterable<String> options = Arrays.asList("-d", classesBaseDir, "-cp", sb.toString())
...
Since Java1.7 you can also use Files.newDirectoryStream(Path) instead of list(File). With 1.8 you could even call join instead of joining manually.

"Error: Could not find or load main class My.class"

Im using Java SDK 1.7 on Windows 7 via cmd.exe . Up until a few hours ago everything was working correctly when suddenly I was unable to run my compiled class files, consistently presented with the error in the title.
I seem to be able to compile my My.java file however I am unable to run the resulting class file (My.class). I am constantly given the error "Error: Could not find or load main class My.class". I have tried this with multiple other class files all resulting in the same problem.
My 'Path' environment variable is set to "C:\Program Files (x86)\Java\jdk1.7.0_05\bin" if you were wondering
I have tried reinstalling, creating and setting a classpath variable (no luck), and even directly using the
java -cp . My.class
command.
I have tried these posts all to no avail, hence why I'm posting:
Error: Could not find or load main class
Error: Could not find or load main class- Novice
Could not find or load main class
Java 1.7.0_03 Error: Could not find or load main class
If it makes any difference my code is :
import javax.swing.JOptionPane;
class My {
public static void main(String[] args) {
final double x = 3.2;
int i = (int)x;
double m = 0;
if (x < 4) {
String saySomething = JOptionPane.showInputDialog(i);
System.out.println(saySomething);
}
else {
String saySomething = JOptionPane.showInputDialog(i);
System.out.println("Hello World");
}
while (m < 10) {
System.out.print(" While Loop ");
m++;
};
for (i=1; i < 10; i++) {
System.out.println("For Loop");
};
}
}

You should specify the classname instead of the file of the class to load. The difference is a simple matter of removing the .class extension.

I would use an IDE and you shouldn't get these issues. Compile and run is just a click of the mouse.
BTW to run your program from the command line
java -cp . My
You don't add .class

Position yourself in a directory of your project (you need to have src and bin directories there, assuming you keep sources in src and binaries in bin)
java -cp bin My

I myself was facing the same problem. It was happening because I was being remiss in typing the name of the class properly. In my instance, I was typing
java doubler
instead of
java Doubler