cn.imethan.common.repository.DynamicSpecifications.java Source code

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Here is the source code for cn.imethan.common.repository.DynamicSpecifications.java

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/*******************************************************************************
 * Copyright (c) 2005, 2014 springside.github.io
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 *******************************************************************************/
package cn.imethan.common.repository;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaBuilder.In;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Path;
import javax.persistence.criteria.Predicate;
import javax.persistence.criteria.Root;

import org.apache.commons.lang3.StringUtils;
import org.springframework.data.jpa.domain.Specification;

import com.google.common.collect.Lists;

/**
 * DynamicSpecifications.java
 *
 * @author Ethan Wong
 * @since JDK 1.7
 * @datetime 201617?11:30:26
 */
public class DynamicSpecifications {

    public static <T> Specification<T> bySearchFilter(final Collection<SearchFilter> filters,
            final Class<T> entityClazz) {
        return new Specification<T>() {
            @Override
            public Predicate toPredicate(Root<T> root, CriteriaQuery<?> query, CriteriaBuilder builder) {
                if (filters != null && !filters.isEmpty()) {

                    List<Predicate> predicates = Lists.newArrayList();
                    for (SearchFilter filter : filters) {
                        // nested path translate, Task??"user.name"filedName, ?Task.user.name
                        String[] names = StringUtils.split(filter.fieldName, ".");
                        Path expression = root.get(names[0]);
                        try {
                            for (int i = 1; i < names.length; i++) {
                                expression = expression.get(names[i]);
                            }
                        } catch (Exception e) {
                            e.printStackTrace();
                        }

                        // logic operator
                        switch (filter.operator) {
                        case EQ:
                            predicates.add(builder.equal(expression, filter.value));
                            break;
                        case LIKE:
                            predicates.add(builder.like(expression, "%" + filter.value + "%"));
                            break;
                        case GT:
                            predicates.add(builder.greaterThan(expression, (Comparable) filter.value));
                            break;
                        case LT:
                            predicates.add(builder.lessThan(expression, (Comparable) filter.value));
                            break;
                        case GTE:
                            predicates.add(builder.greaterThanOrEqualTo(expression, (Comparable) filter.value));
                            break;
                        case LTE:
                            predicates.add(builder.lessThanOrEqualTo(expression, (Comparable) filter.value));
                            break;
                        case IN:
                            In in = builder.in(expression);
                            String[] valueStrings = StringUtils.split(filter.value.toString(), ",");
                            List<Long> list = new ArrayList<Long>();
                            for (String value : valueStrings) {
                                list.add(Long.valueOf(value.trim()));
                            }
                            in.value(list);

                            predicates.add(in);

                            break;
                        case NOTIN:
                            In in1 = builder.in(expression);
                            String[] valueStrings1 = StringUtils.split(filter.value.toString(), ",");
                            List<Long> list1 = new ArrayList<Long>();
                            for (String value : valueStrings1) {
                                list1.add(Long.valueOf(value.trim()));
                            }
                            in1.value(list1);

                            predicates.add(builder.not(in1));
                            break;
                        }
                    }

                    // ? and ???
                    if (!predicates.isEmpty()) {
                        return builder.and(predicates.toArray(new Predicate[predicates.size()]));
                    }
                }

                //            //hibernate
                //            //org.hibernate.ejb.criteria.CriteriaQueryImpl
                //            if(query instanceof org.hibernate.ejb.QueryImpl) {  
                //               @SuppressWarnings("rawtypes")
                //               org.hibernate.ejb.QueryImpl hibernateQuery = (org.hibernate.ejb.QueryImpl)query;  
                //               org.hibernate.Query hQuery = hibernateQuery.getHibernateQuery();
                //               hQuery.setCacheable(true);
                //            }

                return builder.conjunction();
            }
        };
    }
}