ResidentMavenInvoker.java
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* to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
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package org.apache.maven.cling.invoker.mvn.resident;
import java.util.ArrayList;
import java.util.concurrent.ConcurrentHashMap;
import java.util.function.Consumer;
import org.apache.maven.api.annotations.Nullable;
import org.apache.maven.api.cli.InvokerException;
import org.apache.maven.api.cli.InvokerRequest;
import org.apache.maven.api.cli.mvn.MavenOptions;
import org.apache.maven.api.services.Lookup;
import org.apache.maven.cling.invoker.LookupContext;
import org.apache.maven.cling.invoker.mvn.MavenContext;
import org.apache.maven.cling.invoker.mvn.MavenInvoker;
/**
* Resident invoker implementation, specialization of Maven Invoker, but keeps Maven instance resident. This implies, that
* things like environment, system properties, extensions etc. are loaded only once. It is caller duty to ensure
* that subsequent call is right for the resident instance (ie no env change or different extension needed).
* This implementation "pre-populates" MavenContext with pre-existing stuff (except for very first call)
* and does not let DI container to be closed.
*/
public class ResidentMavenInvoker extends MavenInvoker {
private final ConcurrentHashMap<String, MavenContext> residentContext;
public ResidentMavenInvoker(Lookup protoLookup, @Nullable Consumer<LookupContext> contextConsumer) {
super(protoLookup, contextConsumer);
this.residentContext = new ConcurrentHashMap<>();
}
@Override
public void close() throws InvokerException {
ArrayList<Exception> exceptions = new ArrayList<>();
for (MavenContext context : residentContext.values()) {
try {
context.doCloseContainer();
} catch (Exception e) {
exceptions.add(e);
}
}
if (!exceptions.isEmpty()) {
InvokerException exception = new InvokerException("Could not cleanly shut down context pool");
exceptions.forEach(exception::addSuppressed);
throw exception;
}
}
@Override
protected MavenContext createContext(InvokerRequest invokerRequest) {
// TODO: in a moment Maven stop pushing user properties to system properties (and maybe something more)
// and allow multiple instances per JVM, this may become a pool? derive key based in invokerRequest?
MavenContext result = residentContext.computeIfAbsent(
"resident",
k -> new MavenContext(invokerRequest, false, (MavenOptions)
invokerRequest.options().orElse(null)));
return copyIfDifferent(result, invokerRequest);
}
protected MavenContext copyIfDifferent(MavenContext mavenContext, InvokerRequest invokerRequest) {
if (invokerRequest == mavenContext.invokerRequest) {
return mavenContext;
}
MavenContext shadow = new MavenContext(
invokerRequest, false, (MavenOptions) invokerRequest.options().orElse(null));
// we carry over only "resident" things
shadow.containerCapsule = mavenContext.containerCapsule;
shadow.lookup = mavenContext.lookup;
shadow.eventSpyDispatcher = mavenContext.eventSpyDispatcher;
shadow.simplexTransferListener = mavenContext.simplexTransferListener;
shadow.maven = mavenContext.maven;
return shadow;
}
}