• HibernateCRUD基础框架(1)-实体类


    HibernateCRUD基础框架包括3篇文章,主要讲述整个CRUD基础框架的思路。

    第1篇:讲述最基本的实体类,这些实体类是对SQL语言中的一些概念的封装。

    第2篇:在这些实体类的基础上,开发一个“HQL语句构造器-HqlQueryBuilder”。

    第3篇:构建一套简单的和较为复杂的标准的CRUD API。


    优点:提高代码复用,提升编码效率。

    缺点:没有过多考虑性能,具体性能没有去检验。

          功能有限,只是针对常用的和较为简单的CRUD功能。


    友情提示:注释已经写得比较清楚了,不再过多解释。

                        有问题,可以留言,抽空答复。


    第1篇:实体类

    1.常量和基础定义

    package cn.fansunion.hibernate.sql;
    
    /**
     * SQL关键字常量“and,like,where”,比较符常量">,<,="等常量。
     *
     * @author LeiWen@FansUnion.cn
     */
    public class ConstantBase {
    
        /**
         * SQL关键字or
         */
        public static final String OR = "or";
        /**
         * SQL关键字and
         */
        public static final String AND = "and";
        /**
         * SQL关键字from
         */
        public static final String FROM = "from";
        /**
         * SQL关键字as
         */
        public static final String AS = "as";
        /**
         * SQL关键字where
         */
        public static final String WHERE = "where";
        /**
         * SQL关键字asc
         */
        public static final String ASC = "asc";
        /**
         * SQL关键字desc
         */
        public static final String DESC = "desc";
        /**
         * SQL关键字in
         */
        public static final String IN = "in";
        /**
         * not in
         */
        public static final String NOT_IN = "not in";
        /**
         * SQL关键字like
         */
        public static final String LIKE = "like";
        /**
         * not like
         */
        public static final String NOT_LIKE = "not like";
        /**
         * order by
         */
        public static final String ORDER_BY = "order by";
        /**
         * group by
         */
        public static final String GROUP_BY = "group by";
        /**
         * SQL关键字limit
         */
        public static final String LIMIT = "limit";
        /**
         * 冒号
         */
        public static final String COLON = ":";
        /**
         * 逗号
         */
        public static final String COMMA = ",";
        /**
         * 一个空格
         */
        public static final String BLANK = " ";
        /**
         * 一个空字符串
         */
        public static final String EMPTY = "";
        /**
         *
         */
        public static final boolean AUTO_ADD = true;
        /**
         * 右括号
         */
        public static final String RIGHT_BRACKET = ")";
        /**
         * 左括号
         */
        public static final String LEFT_BRACKET = "(";
        /**
         * 百分号
         */
        public static final String PERCENT = "%";
        /**
         * 单引号
         */
        public static final String SINGLE_QUOTATION_MARK = "'";
        /**
         * 等号
         */
        public static final String EQUALS = "=";
        /**
         * 不等
         */
        public static final String NOT_EQUALS = "!=";
        /**
         * 大于号
         */
        public static final String GREAT_THAN = ">";
        /**
         * 小于号
         */
        public static final String LESS_THAN = "<";
        /**
         * 大于等于
         */
        public static final String GREAT_THAN_EQUALS = ">=";
        /**
         * 小于等于
         */
        public static final String LESS_THAN_EQUALS = "<=";
    
        // *************************************
        // **********左右分别加1个空格的常量*****************
        // *************************************
        public static final String EQUALS_WITH_BLANK = buildBlank(EQUALS);
        public static final String NOT_EQUALS_WITH_BLANK = buildBlank(NOT_EQUALS);
    
        public static final String GREAT_THAN_WITH_BLANK = buildBlank(GREAT_THAN);
        public static final String LESS_THAN_WITH_BLANK = buildBlank(LESS_THAN);
    
        public static final String GREAT_THAN_EQUALS_WITH_BLANK = buildBlank(GREAT_THAN_EQUALS);
        public static final String LESS_THAN_EQUALS_WITH_BLANK = buildBlank(LESS_THAN_EQUALS);
    
        public static final String IN_WITH_BLANK = buildBlank(IN);
        public static final String NOT_IN_WITH_BLANK = buildBlank(NOT_IN);
    
        public static final String LIKE_WITH_BLANK = buildBlank(LIKE);
        public static final String NOT_LIKE_WITH_BLANK = buildBlank(NOT_LIKE);
    
        public static final String ORDER_BY_WITH_BLANK = buildBlank(ORDER_BY);
        public static final String GROUP_BY_WITH_BLANK = buildBlank(GROUP_BY);
    
        public static final String LIMIT_WITH_BLANK = buildBlank(LIMIT);
        public static final String WHERE_WITH_BLANK = buildBlank(WHERE);
        public static final String AS_WITH_BLANK = buildBlank(AS);
    
        /**
         * 返回变量对应的字符串值
         *
         * @param or
         * @return true返回“or”,false返回"and"
         */
        public static String isOr(Boolean or) {
            String str = AND;
            if (or) {
                str = OR;
            }
            return str;
        }
    
        /**
         * 在字符串的左边加上百分号"%",在字符串的右边加上百分号"%"
         *
         * @param str
         *            字符串
         * @return 被"%%"包围起来的新的字符串
         */
        public static String buildLike(Object str) {
            String newStr = PERCENT + str + PERCENT;
            return newStr;
        }
    
        /**
         * 在一个字符串的左边和右边都加上一个空格
         *
         * @param str
         * @return 新的字符串
         */
        public static String buildBlank(Object str) {
            String newStr = BLANK + str + BLANK;
            return newStr;
        }
    
        /**
         * 在字符串的左边和右边加上单引号"'"
         *
         * @param str
         *            字符串
         * @return 被"''"包围起来的新的字符串
         */
        public static String buildQuota(Object str) {
            String newStr = SINGLE_QUOTATION_MARK + str + SINGLE_QUOTATION_MARK;
            return newStr;
        }
    
        /**
         * 在字符串的左边加上左括号"(",在字符串的右边加上右括号")"
         *
         * @param str
         *            字符串
         * @return 被"()"包围起来的新的字符串
         */
        public static String buildBracket(Object str) {
            String newStr = LEFT_BRACKET + str + RIGHT_BRACKET;
            return newStr;
        }
    
        public static void println(Object object) {
            System.out.println(object);
        }
    
        public static void print(Object object) {
            System.out.print(object);
        }
    }

    package cn.fansunion.hibernate.sql;
    
    /**
     * 操作符的类型,如"= != > >= < <="。
     *
     * @author LeiWen@FansUnion.cn
     */
    public enum Operator {
    
        EQUALS, NOT_EQUALS, GREAT_THAN, GREAT_THAN_EQUALS, LESS_THAN, LESS_THAN_EQUALS, LIKE, NOT_LIKE, IN, NOT_IN;
        /**
         * 转化为字符串(TODO 放在一个单独的工具类里比较合适)
         */
        public static String toString(Operator operator) {
            String str = "";
    
            switch (operator) {
            case EQUALS:
                str = ConstantBase.EQUALS;
                break;
    
            case NOT_EQUALS:
                str = ConstantBase.NOT_EQUALS;
                break;
    
            case GREAT_THAN:
                str = ConstantBase.GREAT_THAN;
                break;
    
            case GREAT_THAN_EQUALS:
                str = ConstantBase.GREAT_THAN_EQUALS;
                break;
    
            case LESS_THAN:
                str = ConstantBase.LESS_THAN;
                break;
    
            case LESS_THAN_EQUALS:
                str = ConstantBase.LESS_THAN_EQUALS;
                break;
    
            case LIKE:
                str = ConstantBase.LIKE;
                break;
    
            case NOT_LIKE:
                str = ConstantBase.NOT_LIKE;
                break;
    
            case IN:
                str = ConstantBase.IN;
                break;
    
            case NOT_IN:
                str = ConstantBase.NOT_IN;
                break;
    
            default:
                break;
            }
            return str;
        }
    }


    public enum AndOr {
        AND, OR
    }

    2.实体类


    package cn.fansunion.hibernate.sql.entity;
    
    import org.apache.commons.lang.StringUtils;
    import org.apache.commons.lang.text.StrBuilder;
    
    import cn.fansunion.hibernate.sql.ConstantBase;
    
    /**
     * From语句,如"from User user"。
     *
     * @author LeiWen@FansUnion.cn
     */
    public class From extends ConstantBase {
        /**
         * 实体类的class,如User.class
         */
        private Class<?> modelClazz;
        /**
         * 实体类Class的字符串表示,如User
         */
        private String model;
        /**
         * 别名,如user
         */
        private String alias;
    
        public From() {
            super();
        }
    
        public From(Class<?> modelClazz) {
            super();
            this.modelClazz = modelClazz;
        }
    
        public From(Class<?> modelClazz, String alias) {
            super();
            this.modelClazz = modelClazz;
            this.alias = alias;
        }
    
        public From(String model) {
            super();
            this.model = model;
        }
    
        public From(String model, String alias) {
            super();
            this.model = model;
            this.alias = alias;
        }
    
        //
        public String getModel() {
            return model;
        }
    
        public void setModel(String model) {
            this.model = model;
        }
    
        public Class<?> getModelClazz() {
            return modelClazz;
        }
    
        public void setModelClazz(Class<?> modelClazz) {
            this.modelClazz = modelClazz;
        }
    
        public String getAlias() {
            return alias;
        }
    
        public void setAlias(String alias) {
            this.alias = alias;
        }
        /**
         * 转化为字符串
         */
        public String toString() {
            if (modelClazz != null) {
                this.model = modelClazz.getSimpleName();
            }
    
            StrBuilder builder = new StrBuilder();
            if (StringUtils.isNotEmpty(model)) {
                builder.append(FROM).append(BLANK)
                        .append(modelClazz.getSimpleName());
                if (StringUtils.isNotEmpty(alias)) {
                    builder.append(AS_WITH_BLANK).append(alias);
                }
            }
    
            return builder.toString();
        }
    
    }


    package cn.fansunion.hibernate.sql.entity;
    
    import java.util.Date;
    
    import cn.fansunion.hibernate.sql.ConstantBase;
    import cn.fansunion.hibernate.sql.Operator;
    
    /**
     * 1个查询条件。由3部分构成,键-操作-值,如 "age > 12 ","email ='LeiWen@FansUnion.cn'"等。
     *
     * @author LeiWen@FansUnion.cn
     */
    public class Condition extends ConstantBase {
        /**
         * 条件的键
         */
        private String key;
        /**
         * 条件的操作符
         */
        private Operator operator;
        /**
         * 条件的值
         */
        private Object value;
    
        public Condition() {
    
        }
    
        public Condition(String key, Operator operator) {
            super();
            this.key = key;
            this.operator = operator;
        }
    
        public Condition(String key, Object value) {
            this.key = key;
            this.value = value;
        }
    
        public Condition(String key, Operator operator, Object value) {
            this.key = key;
            this.operator = operator;
            this.value = value;
        }
    
        public String getKey() {
            return key;
        }
    
        public void setKey(String key) {
            this.key = key;
        }
    
        public Operator getOperator() {
            return operator;
        }
    
        public void setOperator(Operator operator) {
            this.operator = operator;
        }
    
        public Object getValue() {
            return value;
        }
    
        public void setValue(Object value) {
            this.value = value;
        }
    
        /**
         * 转化为字符串
         */
        public String toString() {
            String str = "";
    
            String newValue = "";
            // 构造完整的语句
            if (value != null) {
                // 是否需要自动增加"%%","()"
                if (AUTO_ADD) {
                    switch (operator) {
                    case LIKE:
    
                    case NOT_LIKE:
                        newValue = buildLike(value);
                        break;
    
                    case IN:
                    case NOT_IN:
                        newValue = buildBracket(value);
                        break;
    
                    default:
                        break;
                    }
    
                    // 需要添加引号的类型
                    boolean isString = value instanceof String;
                    boolean isDate = value instanceof Date;
                    boolean isSqlDate = value instanceof java.sql.Date;
                    if (isString || isDate || isSqlDate) {
                        newValue = buildQuota(value);
                    } else {
                        newValue = value.toString();
                    }
    
                }
            }
            // 构造带有占位符的语句
            else {
                newValue = COLON + key;
            }
            // "name=a","name like a",统一都加个空格
            str += key + BLANK + Operator.toString(operator) + BLANK + newValue;
            return str;
        }
    }


    package cn.fansunion.hibernate.sql.entity;
    
    import java.util.ArrayList;
    import java.util.List;
    
    import org.apache.commons.lang.text.StrBuilder;
    
    import cn.fansunion.hibernate.AndOr;
    import cn.fansunion.hibernate.sql.ConstantBase;
    import cn.fansunion.hibernate.util.EmptyUtils;
    
    /**
     * 逻辑上属于1个组的条件。
     *
     * @author LeiWen@FansUnion.cn
     */
    public class GroupCondition extends ConstantBase {
        /**
         * 多个条件构成的集合
         */
        private List<Condition> conditionList;
    
        /**
         * 组内各个条件之间的关系:且|或,默认为且
         */
        private List<Boolean> relationList;
    
        public static final Boolean AND = true;
        public static final Boolean OR = false;
    
        public GroupCondition() {
            conditionList = new ArrayList<Condition>();
            relationList = new ArrayList<Boolean>();
        }
    
        public void addCondition(Condition condition) {
            addCondition(condition, true);
        }
    
        public void addCondition(Condition condition, boolean or) {
            conditionList.add(condition);
            if (EmptyUtils.notEmpty(conditionList)) {
                relationList.add(or);
            }
        }
    
        public void addCondition(Condition condition, AndOr ao) {
            conditionList.add(condition);
            if (EmptyUtils.notEmpty(conditionList)) {
                if (ao == AndOr.AND) {
                    relationList.add(AND);
                } else {
                    relationList.add(OR);
                }
            }
        }
    
        public void addOr(int index, boolean or) {
            relationList.set(index, or);
        }
    
        /**
         * 转化为字符串
         */
        public String toString() {
            if (EmptyUtils.isEmpty(conditionList)) {
                return EMPTY;
            }
    
            StrBuilder builder = new StrBuilder();
            int size = conditionList.size();
            for (int index = 0; index < size; index++) {
                if (index == 0) {
                    builder.append(conditionList.get(index));
                } else {
                    builder.append(BLANK).append(isOr(relationList.get(index)))
                            .append(BLANK).append(conditionList.get(index));
                }
            }
            return builder.toString();
        }
    
    }

    package cn.fansunion.hibernate.sql.entity;
    
    import java.util.ArrayList;
    import java.util.List;
    
    import org.apache.commons.lang.text.StrBuilder;
    
    import cn.fansunion.hibernate.sql.ConstantBase;
    import cn.fansunion.hibernate.util.EmptyUtils;
    
    /**
     * 搜索条件(2个组之间,且|或。)
     *
     * @author LeiWen@FansUnion.cn
     */
    public class SearchCondition extends ConstantBase {
    
        /**
         * 多个组条件构成的集合
         */
        private List<GroupCondition> groupConditionList;
    
        /**
         * 多个组条件之间的关系:且|或,默认为且
         */
        private List<Boolean> and;
    
        public SearchCondition() {
            groupConditionList = new ArrayList<GroupCondition>();
            and = new ArrayList<Boolean>();
    
        }
    
        public void addGroupCondition(GroupCondition groupCondition) {
            addGroupCondition(groupCondition, false);
        }
    
        public void addGroupCondition(GroupCondition groupCondition, boolean or) {
            groupConditionList.add(groupCondition);
            if (EmptyUtils.notEmpty(groupConditionList)) {
                and.add(or);
            }
        }
    
        public void addOr(int index, boolean or) {
            and.set(index, or);
        }
    
        public List<GroupCondition> getGroupConditionList() {
            return groupConditionList;
        }
    
        public void setGroupConditionList(List<GroupCondition> groupConditionList) {
            this.groupConditionList = groupConditionList;
        }
    
        public List<Boolean> getAnd() {
            return and;
        }
    
        public void setAnd(List<Boolean> and) {
            this.and = and;
        }
    
        /**
         * 转化为字符串
         */
        public String toString() {
            if (EmptyUtils.isEmpty(groupConditionList)) {
                return EMPTY;
            }
    
            StrBuilder builder = new StrBuilder();
    
            int size = groupConditionList.size();
            for (int index = 0; index < size; index++) {
                // 1个组的条件用()包起来
                if (index == 0) {
                    builder.append(WHERE_WITH_BLANK).append(
                            buildBracket(groupConditionList.get(index)));
    
                } else {
                    builder.append(BLANK).append(isOr(and.get(index)))
                            .append(BLANK)
                            .append(buildBracket(groupConditionList.get(index)));
                }
            }
    
            return builder.toString();
        }
    }

    package cn.fansunion.hibernate.sql.entity;
    
    import org.apache.commons.lang.StringUtils;
    import org.apache.commons.lang.text.StrBuilder;
    
    import cn.fansunion.hibernate.sql.ConstantBase;
    
    /**
     *
     * 排序语句,如“order by id desc”。
     *
     * @author LeiWen@FansUnion.cn
     */
    public class Order extends ConstantBase {
        /**
         * 排序语句的键
         */
        private String key;
        /**
         * 排序语句的升序或降序(字符串形式)
         */
        private String asc;
        /**
         * 排序语句的升序或降序(布尔形式)
         */
        private Boolean isAsc;
    
        public Order() {
    
        }
    
        public Order(String key, String asc) {
            this.key = key;
            this.asc = asc;
        }
    
        public Order(String key, Boolean isAsc) {
            super();
            this.key = key;
            this.isAsc = isAsc;
        }
    
        /**
         * 转化为字符串
         */
        public String toString() {
            String finalSort = DESC;
    
            if (StringUtils.isNotEmpty(asc)) {
                finalSort = asc;
            } else {
                if (isAsc) {
                    finalSort = ASC;
                }
            }
    
            StrBuilder builder = new StrBuilder();
            builder.append(key).append(BLANK).append(finalSort);
            return builder.toString();
        }
    
    }

    package cn.fansunion.hibernate.sql.entity;
    
    import java.util.ArrayList;
    import java.util.List;
    
    import org.apache.commons.lang.text.StrBuilder;
    
    import cn.fansunion.hibernate.sql.ConstantBase;
    import cn.fansunion.hibernate.util.ListUtils;
    
    /**
     * 排序组,如"order by id desc,name asc"。
     *
     * @author LeiWen@FansUnion.cn
     */
    public class OrderGroup extends ConstantBase {
        /**
         * 多个排序构成的集合
         */
        private List<Order> orderList;
    
        public OrderGroup() {
            orderList = new ArrayList<Order>();
        }
    
        public OrderGroup(Order order) {
            this();
            orderList.add(order);
        }
    
        public OrderGroup(Order order1, Order order2) {
            this();
            orderList.add(order1);
            orderList.add(order2);
        }
    
        public void addOrder(Order order) {
            orderList.add(order);
        }
        /**
         * 转化为字符串
         */
        public String toString() {
            StrBuilder builder = new StrBuilder();
            if (ListUtils.notEmpty(orderList)) {
                String orders = ListUtils.list2String(orderList);
                builder.append(ORDER_BY_WITH_BLANK).append(orders);
            }
            return builder.toString();
        }
    
    }

    package cn.fansunion.hibernate.sql.entity;
    
    import java.util.ArrayList;
    import java.util.List;
    
    import cn.fansunion.hibernate.sql.ConstantBase;
    import cn.fansunion.hibernate.util.EmptyUtils;
    import cn.fansunion.hibernate.util.ListUtils;
    
    /**
     * 分组语句,如"group by id,name"。
     *
     * @author LeiWen@FansUnion.cn
     */
    public class GroupBy extends ConstantBase {
    
        /**
         * 分组的字段名称构成的集合,暂时不支持having子句
         */
        private List<String> group;
    
        public GroupBy() {
            group = new ArrayList<String>();
        }
    
        public List<String> getGroup() {
            return group;
        }
    
        /**
         * 转化为字符串
         */
        public String toString() {
            if (EmptyUtils.notEmpty(group)) {
                String groupStr = ListUtils.list2String(group);
                return GROUP_BY_WITH_BLANK + groupStr;
            }
            return EMPTY;
        }
    
        public void addGroup(String g) {
            this.group.add(g);
        }
    }

    原文链接http://blog.fansunion.cn/articles/3616(小雷博客-blog.fansunion.cn)

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  • 原文地址:https://www.cnblogs.com/qitian1/p/6463318.html
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