Add JCommander parameter resolver

src/main/java/org/springframework/shell2/jcommander/JCommanderParameterResolver.java

@@ -0,0 +1,63 @@
+package org.springframework.shell2.jcommander;
+
+import java.lang.annotation.Annotation;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import com.beust.jcommander.DynamicParameter;
+import com.beust.jcommander.JCommander;
+import com.beust.jcommander.Parameter;
+import com.beust.jcommander.ParametersDelegate;
+
+import org.springframework.beans.BeanUtils;
+import org.springframework.core.MethodParameter;
+import org.springframework.shell2.ParameterResolver;
+import org.springframework.util.ReflectionUtils;
+
+/**
+ * Created by ericbottard on 15/12/15.
+ */
+public class JCommanderParameterResolver implements ParameterResolver {
+
+	private static final Collection<Class<? extends Annotation>> JCOMMANDER_ANNOTATIONS =
+			Arrays.asList(Parameter.class, DynamicParameter.class, ParametersDelegate.class);
+
+	@Override
+	public boolean supports(MethodParameter parameter) {
+		AtomicBoolean isSupported = new AtomicBoolean(false);
+
+		Class<?> parameterType = parameter.getParameterType();
+		ReflectionUtils.doWithFields(parameterType, field -> {
+			ReflectionUtils.makeAccessible(field);
+			boolean hasAnnotation = Arrays.asList(field.getAnnotations())
+					.stream()
+					.map(Annotation::annotationType)
+					.anyMatch(JCOMMANDER_ANNOTATIONS::contains);
+			isSupported.compareAndSet(false, hasAnnotation);
+
+		});
+
+		ReflectionUtils.doWithMethods(parameterType, method -> {
+			ReflectionUtils.makeAccessible(method);
+			boolean hasAnnotation = Arrays.asList(method.getAnnotations())
+					.stream()
+					.map(Annotation::annotationType)
+					.anyMatch(Parameter.class::equals);
+			isSupported.compareAndSet(false, hasAnnotation);
+		});
+		return isSupported.get();
+	}
+
+	@Override
+	public Object resolve(MethodParameter methodParameter, List<String> words) {
+		Object pojo = BeanUtils.instantiateClass(methodParameter.getParameterType());
+		JCommander jCommander = new JCommander();
+		jCommander.addObject(pojo);
+		jCommander.setAcceptUnknownOptions(true);
+		jCommander.parse(words.toArray(new String[words.size()]));
+		return pojo;
+	}
+
+}