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package javax.servlet;

import java.util.*;
import javax.servlet.annotation.HttpMethodConstraint;
import javax.servlet.annotation.ServletSecurity;

Java Class representation of a ServletSecurity annotation value. 
Since:
Servlet 3.0/**
 * Java Class representation of a {@link ServletSecurity} annotation value.
 *
 * @since Servlet 3.0
 */
public class ServletSecurityElement extends HttpConstraintElement {

    private Collection<String> methodNames;
    private Collection<HttpMethodConstraintElement> methodConstraints;

    
Constructs an instance using the default
HttpConstraintElement value as the default Constraint
element and with no HTTP Method specific constraint elements.
/**
     * Constructs an instance using the default
     * <code>HttpConstraintElement</code> value as the default Constraint
     * element and with no HTTP Method specific constraint elements.
     */
    public ServletSecurityElement() {
        methodConstraints = new HashSet<HttpMethodConstraintElement>();
        methodNames = Collections.emptySet();
    }

    
Constructs an instance with a default Constraint element
and with no HTTP Method specific constraint elements.
Params:
constraint – the HttpConstraintElement to be
applied to all HTTP methods other than those represented in the
methodConstraints/**
     * Constructs an instance with a default Constraint element
     * and with no HTTP Method specific constraint elements.
     *
     * @param constraint the HttpConstraintElement to be
     * applied to all HTTP methods other than those represented in the
     * <tt>methodConstraints</tt>
     */
    public ServletSecurityElement(HttpConstraintElement constraint) {
        super(constraint.getEmptyRoleSemantic(),
                constraint.getTransportGuarantee(),
                constraint.getRolesAllowed());
        methodConstraints = new HashSet<HttpMethodConstraintElement>();
        methodNames = Collections.emptySet();
    }

    
Constructs an instance using the default
HttpConstraintElement value as the default Constraint
element and with a collection of HTTP Method specific constraint
elements.
Params:
methodConstraints – the collection of HTTP method specific
constraint elements
Throws:
IllegalArgumentException – if duplicate method names are
detected/**
     * Constructs an instance using the default
     * <code>HttpConstraintElement</code> value as the default Constraint
     * element and with a collection of HTTP Method specific constraint
     * elements.
     *
     * @param methodConstraints the collection of HTTP method specific
     * constraint elements
     *
     * @throws IllegalArgumentException if duplicate method names are
     * detected
     */
    public ServletSecurityElement(
            Collection<HttpMethodConstraintElement> methodConstraints) {
        this.methodConstraints = (methodConstraints == null ?
            new HashSet<HttpMethodConstraintElement>() : methodConstraints);
        methodNames = checkMethodNames(this.methodConstraints);
    }

    
Constructs an instance with a default Constraint element
and with a collection of HTTP Method specific constraint elements.
Params:
constraint – the HttpConstraintElement to be
applied to all HTTP methods other than those represented in the
methodConstraints
methodConstraints – the collection of HTTP method specific
constraint elements.
Throws:
IllegalArgumentException – if duplicate method names are
detected/**
     * Constructs an instance with a default Constraint element
     * and with a collection of HTTP Method specific constraint elements.
     *
     * @param constraint the HttpConstraintElement to be
     * applied to all HTTP methods other than those represented in the
     * <tt>methodConstraints</tt>
     * @param methodConstraints the collection of HTTP method specific
     * constraint elements.
     *
     * @throws IllegalArgumentException if duplicate method names are
     * detected
     */
    public ServletSecurityElement(HttpConstraintElement constraint,
            Collection<HttpMethodConstraintElement> methodConstraints) {
        super(constraint.getEmptyRoleSemantic(),
                constraint.getTransportGuarantee(),
                constraint.getRolesAllowed());
        this.methodConstraints = (methodConstraints == null ?
            new HashSet<HttpMethodConstraintElement>() : methodConstraints);
        methodNames = checkMethodNames(this.methodConstraints);
    }

    
Constructs an instance from a ServletSecurity annotation value. 
Params:
annotation – the annotation value
Throws:
IllegalArgumentException – if duplicate method names are
detected/**
     * Constructs an instance from a {@link ServletSecurity} annotation value.
     *
     * @param annotation the annotation value
     *
     * @throws IllegalArgumentException if duplicate method names are
     * detected
     */
    public ServletSecurityElement(ServletSecurity annotation) {
        super(annotation.value().value(),
                annotation.value().transportGuarantee(),
                annotation.value().rolesAllowed());
        this.methodConstraints = new HashSet<HttpMethodConstraintElement>();
        for (HttpMethodConstraint constraint :
                annotation.httpMethodConstraints()) {
            this.methodConstraints.add(
                new HttpMethodConstraintElement(
                    constraint.value(),
                    new HttpConstraintElement(constraint.emptyRoleSemantic(),
                        constraint.transportGuarantee(),
                        constraint.rolesAllowed())));
        }
        methodNames = checkMethodNames(this.methodConstraints);
    }

    
Gets the (possibly empty) collection of HTTP Method specific
constraint elements.
If permitted, any changes to the returned Collection must not
affect this ServletSecurityElement.
Returns:
the (possibly empty) collection of HttpMethodConstraintElement
objects/**
     * Gets the (possibly empty) collection of HTTP Method specific
     * constraint elements.
     *
     * <p>If permitted, any changes to the returned <code>Collection</code> must not
     * affect this <code>ServletSecurityElement</code>.
     *
     *
     * @return the (possibly empty) collection of HttpMethodConstraintElement
     * objects
     */
    public Collection<HttpMethodConstraintElement> getHttpMethodConstraints() {
        return Collections.unmodifiableCollection(methodConstraints);
    }

    
Gets the set of HTTP method names named by the HttpMethodConstraints.
 
If permitted, any changes to the returned Collection must not
affect this ServletSecurityElement.
Returns:
the collection String method names/**
     * Gets the set of HTTP method names named by the HttpMethodConstraints.
     *
     *  <p>If permitted, any changes to the returned <code>Collection</code> must not
     * affect this <code>ServletSecurityElement</code>.
     *

     *
     * @return the collection String method names
     */
    public Collection<String> getMethodNames() {
        return Collections.unmodifiableCollection(methodNames);
    }

    
Checks for duplicate method names in methodConstraints.
Params:
methodConstraints – 
Throws:
IllegalArgumentException – if duplicate method names are
detected
@retrun
Set of method names/**
     * Checks for duplicate method names in methodConstraints.
     *
     * @param methodConstraints
     *
     * @retrun Set of method names
     *
     * @throws IllegalArgumentException if duplicate method names are
     * detected
     */
    private Collection<String> checkMethodNames(
            Collection<HttpMethodConstraintElement> methodConstraints) {
        Collection<String> methodNames = new HashSet<String>();
        for (HttpMethodConstraintElement methodConstraint :
                        methodConstraints) {
            String methodName = methodConstraint.getMethodName();
            if (!methodNames.add(methodName)) {
                throw new IllegalArgumentException(
                    "Duplicate HTTP method name: " + methodName);
            }
        }
        return methodNames;
    }
}