com.google.inject.internal.SingleParameterInjector Maven / Gradle / Ivy
package com.google.inject.internal;
import com.google.inject.spi.Dependency;
/**
* Resolves a single parameter, to be used in a constructor or method invocation.
*/
final class SingleParameterInjector {
private static final Object[] NO_ARGUMENTS = {};
private final Dependency dependency;
private final Object source;
private final InternalFactory extends T> factory;
SingleParameterInjector(Dependency dependency, BindingImpl extends T> binding) {
this.dependency = dependency;
this.source = binding.getSource();
this.factory = binding.getInternalFactory();
}
/**
* Returns an array of parameter values.
*/
static Object[] getAll(InternalContext context,
SingleParameterInjector>[] parameterInjectors) throws InternalProvisionException {
if (parameterInjectors == null) {
return NO_ARGUMENTS;
}
int size = parameterInjectors.length;
Object[] parameters = new Object[size];
// optimization: use manual for/each to save allocating an iterator here
for (int i = 0; i < size; i++) {
parameters[i] = parameterInjectors[i].inject(context);
}
return parameters;
}
T inject(InternalContext context) throws InternalProvisionException {
Dependency localDependency = dependency;
Dependency> previous = context.pushDependency(localDependency, source);
try {
return factory.get(context, localDependency, false);
} catch (InternalProvisionException ipe) {
throw ipe.addSource(localDependency);
} finally {
context.popStateAndSetDependency(previous);
}
}
}