source: src/main/java/geniusweb/partiesserver/repository/AvailableJavaParty.java

package geniusweb.partiesserver.repository;

import geniusweb.actions.PartyId;
import geniusweb.party.Capabilities;
import geniusweb.party.Party;

/**
 * An approved and ready to run party.
 */
public class AvailableJavaParty implements AvailableParty {

        private final Class<? extends Party> partyclass;
        private final String name;
        private final transient Capabilities capabilities;
        private final transient String description;

        /**
         * 
         * @param name       the filename. This is not a {@link PartyId}.
         * @param partyclass the class of the party.
         * @throws ClassNotFoundException if unknown partyclass
         */
        public AvailableJavaParty(String name, Class<? extends Party> partyclass)
                        throws ClassNotFoundException {
                this.name = name;
                this.partyclass = partyclass;

                Party party;
                try {
                        party = partyclass.newInstance();
                } catch (Throwable e) {
                        throw new ClassNotFoundException(
                                        "Could not instantiate " + partyclass, e);
                }
                capabilities = party.getCapabilities();
                description = party.getDescription();

        }

        @Override
        public String getID() {
                return name;
        }

        @Override
        public String getName() {
                return name;
        }

        /**
         * 
         * @return cached copy of what was received from a call to
         *         {@link Party#getDescription()}.
         */
        @Override
        public String getDescription() {
                return description;
        }

        /**
         * 
         * @return cached copy of what was received from a call to
         *         {@link AvailableParty#getCapabilities()}
         */
        @Override
        public Capabilities getCapabilities() {
                return capabilities;
        }

        @Override
        public Party getInstance() throws InstantiationFailedException {
                try {
                        return partyclass.newInstance();
                } catch (Exception e) {
                        throw new InstantiationFailedException(
                                        "Failed to create instance of party " + this, e);
                }
        }

        @Override
        public void free() {
                // FAIK we can not unload the class or free resources.
                // it would be done automatically if our classloader
                // is garbage collected.
        }

        @Override
        public int hashCode() {
                final int prime = 31;
                int result = 1;
                result = prime * result + ((name == null) ? 0 : name.hashCode());
                result = prime * result
                                + ((partyclass == null) ? 0 : partyclass.hashCode());
                return result;
        }

        @Override
        public boolean equals(Object obj) {
                if (this == obj)
                        return true;
                if (obj == null)
                        return false;
                if (getClass() != obj.getClass())
                        return false;
                AvailableJavaParty other = (AvailableJavaParty) obj;
                if (name == null) {
                        if (other.name != null)
                                return false;
                } else if (!name.equals(other.name))
                        return false;
                if (partyclass == null) {
                        if (other.partyclass != null)
                                return false;
                } else if (!partyclass.equals(other.partyclass))
                        return false;
                return true;
        }

        @Override
        public String toString() {
                return name + " (" + partyclass + ")";
        }

}