rest.ws.gson.deserializer.request.EntityRequestDeserializer.java Source code

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Here is the source code for rest.ws.gson.deserializer.request.EntityRequestDeserializer.java

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package rest.ws.gson.deserializer.request;

import com.google.gson.JsonDeserializationContext;
import com.google.gson.JsonDeserializer;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParseException;
import static rest.ws.dao.DAOFactory.*;
import rest.ws.dao.EntityDAO;
import rest.gson.common.Log;
import rest.gson.common.LogLevel;
import rest.ws.gson.message.Message;
import static rest.gson.common.MessageReservedWord.*;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.lang.reflect.Field;
import java.lang.reflect.Type;
import java.lang.annotation.Annotation;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.persistence.EntityManager;
import javax.persistence.GeneratedValue;
import javax.validation.ConstraintViolation;
import javax.validation.ConstraintViolationException;
import javax.validation.Validation;
import javax.validation.ValidatorFactory;
import javax.validation.Validator;
import javax.validation.constraints.NotNull;

/**
 *
 * @author alexander.escalona
 */
public abstract class EntityRequestDeserializer<T> implements JsonDeserializer<Message> {
    protected EntityManager entityManager;
    protected String dataType;
    protected Class<T> clazz;
    protected T entity;

    public EntityRequestDeserializer(String dataType, Class<T> clazz, EntityManager entityManager) {
        this.entityManager = entityManager;
        this.dataType = dataType;
        this.clazz = clazz;
    }

    @Override
    public Message deserialize(JsonElement je, Type type, JsonDeserializationContext jdc)
            throws JsonParseException {
        JsonObject jsonObject = je.getAsJsonObject();
        if (jsonObject.has(DATA)) {
            try {
                JsonDeserializer<T> deserializer = getEntityDeserializer();
                if (deserializer == null) {
                    Log log = new Log.LogBuilder(LogLevel.ERROR).codeKey(String.valueOf(500))
                            .codeStr(NullPointerException.class.getCanonicalName())
                            .userMsg(String.format("You must register an Entity Merge Deserializer for '%s' entity",
                                    clazz.getCanonicalName()))
                            .build();
                    return new Message.MessageBuilder(getOperationErrorType()).addLog(log).build();
                }
                entity = deserializer.deserialize(jsonObject.get(DATA), clazz, jdc);

                ValidatorFactory factory = Validation.buildDefaultValidatorFactory();
                Validator validator = factory.getValidator();
                Set<ConstraintViolation<T>> uncheckedConstraintViolations = validator.validate(entity);
                if (uncheckedConstraintViolations.size() > 0) {
                    List<ConstraintViolation<T>> constraintViolations = new ArrayList<>();

                    uncheckedConstraintViolations.stream().forEach((ConstraintViolation<T> constraint) -> {
                        boolean add = true;
                        if (constraint.getConstraintDescriptor().getAnnotation() instanceof NotNull)
                            try {
                                Field field = constraint.getRootBeanClass()
                                        .getDeclaredField(constraint.getPropertyPath().toString());
                                for (Annotation a : field.getDeclaredAnnotations())
                                    if (a instanceof GeneratedValue)
                                        add = false;
                            } catch (NoSuchFieldException | SecurityException ex) {
                                Logger.getLogger(EntityRequestDeserializer.class.getName()).log(Level.SEVERE, null,
                                        ex);
                            }
                        if (add)
                            constraintViolations.add(constraint);
                    });
                    if (constraintViolations.size() > 0) {
                        Message.MessageBuilder messageBuilder = new Message.MessageBuilder(getOperationErrorType());
                        constraintViolations.stream().forEach((constraint) -> {
                            messageBuilder.addLog(new Log.LogBuilder(LogLevel.ERROR).codeKey(String.valueOf(412))
                                    .codeStr(ConstraintViolationException.class.getCanonicalName()).userMsg("")
                                    .userMsg(String.format("On '%s' entity the property '%s' violates: %s",
                                            constraint.getRootBeanClass().getCanonicalName(),
                                            constraint.getPropertyPath(), constraint.getMessage()))
                                    .build());
                        });
                        return messageBuilder.build();
                    }
                }

                doEntityAction(createEntityDAO(clazz, entityManager));
                return getResponse();
            } catch (Exception ex) {
                StringWriter errors = new StringWriter();
                ex.printStackTrace(new PrintWriter(errors));
                Log log = new Log.LogBuilder(LogLevel.ERROR).codeKey(String.valueOf(500))
                        .codeStr(ex.getClass().getCanonicalName()).userMsg(errors.toString()).build();
                return new Message.MessageBuilder(getOperationErrorType()).addLog(log).build();
            }

        } else {
            Log log = new Log.LogBuilder(LogLevel.ERROR).codeKey(String.valueOf(400)).codeStr("Bad Request")
                    .userMsg(String.format("Request protocol error. The '%s' property is missed", DATA)).build();
            return new Message.MessageBuilder(getOperationErrorType()).addLog(log).build();
        }
    }

    public abstract JsonDeserializer<T> getEntityDeserializer();

    public abstract void doEntityAction(EntityDAO<T> dao);

    public abstract Message getResponse();

    public abstract String getOperationErrorType();

}