package org.bndtools.templating.engine.mustache;
import com.github.mustachejava.Binding;
import com.github.mustachejava.Code;
import com.github.mustachejava.ObjectHandler;
import com.github.mustachejava.TemplateContext;
import com.github.mustachejava.reflect.BaseObjectHandler;
import com.github.mustachejava.util.GuardException;
import com.github.mustachejava.util.Wrapper;
/**
* A Mustache ObjectHandler that throws an error if a template parameter is unbound.
*/
class CheckMissingObjectHandler extends BaseObjectHandler {
private final ObjectHandler delegateHandler;
CheckMissingObjectHandler(ObjectHandler delegateHandler) {
this.delegateHandler = delegateHandler;
}
@Override
public Wrapper find(final String name, Object[] scopes) {
final Wrapper delegateWrapper = delegateHandler.find(name, scopes);
return new Wrapper() {
@Override
public Object call(Object[] scopes) throws GuardException {
Object value = delegateWrapper.call(scopes);
// System.out.printf("Wrapper.call() [name=%s] -> %s%n", name, value);
if (value == null)
throw new IllegalArgumentException(String.format("Missing value for %s", name));
return value;
}
};
}
@Override
public Binding createBinding(final String name, TemplateContext context, Code code) {
final Binding delegateBinding = delegateHandler.createBinding(name, context, code);
return new Binding() {
@Override
public Object get(Object[] scopes) {
Object value = delegateBinding.get(scopes);
// System.out.printf("Binding.get() [name=%s] -> %s%n", name, value);
if (value == null)
throw new IllegalArgumentException(String.format("Missing value for %s", name));
return value;
}
};
}
}