com.enterprisemath.dao.big.BigEntity Maven / Gradle / Ivy

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package com.enterprisemath.dao.big;

import com.enterprisemath.utils.DomainUtils;
import com.enterprisemath.utils.ValidationUtils;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;
import org.apache.commons.lang3.builder.EqualsBuilder;
import org.apache.commons.lang3.builder.HashCodeBuilder;
import org.apache.commons.lang3.builder.ToStringBuilder;

/**
 * Big entity object. This object is used as a data exchange for the data access handling
 * huge amount of records. Big entity is capable to handle the following data types.
 * 
 * Boolean, integer, Double, String
 * Enumeration - handled by conversion to the string using methods name() and valueOf()
 * Date
 * 
 *
 * @author radek.hecl
 */
public class BigEntity {

    /**
     * Builder object.
     */
    public static class Builder {

        /**
         * Unique identification code.
         */
        public String code;

        /**
         * Fields.
         */
        private Map fields = new HashMap();

        /**
         * Sets code of the entity. This is unique identifier.
         *
         * @param code code of the entity
         * @return this instance
         */
        public Builder setCode(String code) {
            this.code = code;
            return this;
        }

        /**
         * Adds generic field.
         *
         * @param key key
         * @param value value
         * @return this instance
         */
        public Builder addField(String key, Object value) {
            if (value == null) {
                fields.put(key, value);
            }
            else if (value.getClass().isEnum()) {
                Enum enm = (Enum) value;
                fields.put(key, enm.name());
            }
            else {
                fields.put(key, value);
            }
            return this;
        }

        /**
         * Adds string field.
         *
         * @param key key
         * @param value value
         * @return this instance
         */
        public Builder addStringField(String key, String value) {
            fields.put(key, value);
            return this;
        }

        /**
         * Sets fields.
         *
         * @param fields fields
         * @return this instance
         */
        public Builder setFields(Map fields) {
            this.fields = DomainUtils.softCopyMap(fields);
            return this;
        }

        /**
         * Builds the result object.
         *
         * @return create object
         */
        public BigEntity build() {
            return new BigEntity(this);
        }
    }

    /**
     * Unique identification code.
     */
    public String code;

    /**
     * Fields.
     */
    private Map fields;

    /**
     * Creates new instance.
     *
     * @param builder builder object
     */
    public BigEntity(Builder builder) {
        code = builder.code;
        fields = DomainUtils.softCopyUnmodifiableMap(builder.fields);
        guardInvariants();
    }

    /**
     * Guards this object to be consistent. Throws exception if this is not the case.
     */
    private void guardInvariants() {
        ValidationUtils.guardNotEmpty(code, "code cannot be empty");
        ValidationUtils.guardNotEmptyStringInCollection(fields.keySet(), "fields cannot have empty key");
    }

    /**
     * Returns code of this entity. This is the unique identifier.
     *
     * @return code of this entity as a unique identifier
     */
    public String getCode() {
        return code;
    }

    /**
     * Returns fields.
     *
     * @return fields
     */
    public Map getFields() {
        return fields;
    }

    /**
     * Returns specified field.
     *
     * @param  field type
     * @param key key
     * @param clazz class type
     * @return field value, null if field is not defined
     */
    public  T getField(String key, Class clazz) {
        if (fields.get(key) == null) {
            return null;
        }
        else if (clazz.isEnum()) {
            return (T) createEnum(clazz, (String) fields.get(key));
        }
        return (T) fields.get(key);
    }

    /**
     * Returns string fields.
     *
     * @param key key
     * @return property value
     */
    public String getStringField(String key) {
        return (String) fields.get(key);
    }

    /**
     * Creates enumeration.
     *
     * @param clazz enumeration class
     * @param value string representation
     * @return created enumeration
     */
    private Object createEnum(Class clazz, String value) {
        try {
            Method method = clazz.getMethod("valueOf", String.class);
            Object res = method.invoke(null, value);
            return res;
        } catch (NoSuchMethodException e) {
            throw new RuntimeException(e);
        } catch (SecurityException e) {
            throw new RuntimeException(e);
        } catch (IllegalAccessException e) {
            throw new RuntimeException(e);
        } catch (IllegalArgumentException e) {
            throw new RuntimeException(e);
        } catch (InvocationTargetException e) {
            throw new RuntimeException(e);
        }
    }

    @Override
    public int hashCode() {
        return HashCodeBuilder.reflectionHashCode(this);
    }

    @Override
    public boolean equals(Object obj) {
        return EqualsBuilder.reflectionEquals(this, obj);
    }

    @Override
    public String toString() {
        return ToStringBuilder.reflectionToString(this);
    }

}