建造者模式的定义

建造者模式（Builder Pattern）是将一个复杂对象的构建与它的表示分离，使得同样的构建过程可以创建不同的表示。
特征：用户只需要指定需要建造的类型就可以获得对象，建造过程及细节不需要了解
属于创建型模式

建造者模式的适用场景

适用于创建对象需要很多步骤，但是步骤顺序不一定固定
如果一个对象有非常复杂的内部结构（很多属性）
把负载对象的创建和适用分离

建造者模式的优点

封装性好，创建和适用分离
扩展性好，建造类之间独立、一定程度上解耦

建造者模式的缺点

产生多余的Builder对象
产品内部发生变化，建造者都要修改，成本较大

建造者模式在源码中的体现

JDK：StringBuilder
Mybatis：CacheBulider、SqlSessionFactory
Spring：BeanDefinitionBuilder

建造者模式和工厂模式的区别

建造者模式更加注重方法和调用顺序，工厂模式注重于创建对象
创建对象的力度不同，建造者模式创建复杂的对象，由各种复杂部件组成，工厂模式创建出来的都一样
关注点：工厂模式只需要把对象创建出来就可以了，二建造者模式中不就要创建出这个对象，还要知道这个对象由哪些部件组成
建造者模式根据建造过程中的顺序不一样，最终的对象部件组成也不一样

链式编程例子1

import lombok.Data;

public class CourseBuilder {
    private Course course = new Course();

    public CourseBuilder addName(String name) {
        course.setName(name);
        return this;
    }

    public CourseBuilder addPPT(String ppt) {
        course.setPpt(ppt);
        return this;
    }

    public CourseBuilder addVideo(String video) {
        course.setVideo(video);
        return this;
    }

    public CourseBuilder addNote(String note) {
        course.setNote(note);
        return this;
    }

    public CourseBuilder addHomework(String homework) {
        course.setHomework(homework);
        return this;
    }

    public Course build() {
        return this.course;
    }

    @Data
    public class Course {

        private String name;
        private String ppt;
        private String video;
        private String note;

        private String homework;

        @Override
        public String toString() {
            return "CourseBuilder{" +
                    "name='" + name + '\'' +
                    ", ppt='" + ppt + '\'' +
                    ", video='" + video + '\'' +
                    ", note='" + note + '\'' +
                    ", homework='" + homework + '\'' +
                    '}';
        }
    }

}
复制代码

import org.apache.ibatis.mapping.CacheBuilder;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.springframework.beans.factory.support.BeanDefinitionBuilder;

import java.util.Set;

public class Test {
    public static void main(String[] args) {
        CourseBuilder builder = new CourseBuilder()
                    .addName("设计模式")
                    .addPPT("【PPT课件】")
                    .addVideo("【回放视频】")
                    .addNote("【课堂笔记】")
                    .addHomework("【课后作业】");

        System.out.println(builder.build());

        StringBuilder sb = new StringBuilder();
        sb.append("");

        CacheBuilder cacheBuilder = new CacheBuilder("");
        cacheBuilder.blocking(false);
//        cacheBuilder.

        SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder();
//        sqlSessionFactoryBuilder.


        BeanDefinitionBuilder beanDefinitionBuilder = BeanDefinitionBuilder.genericBeanDefinition();
//        beanDefinitionBuilder.
复制代码

链式编程例子构建SQL

import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;

/**
 * QueryRule,主要功能用于构造查询条件
 * 
 * @author Tom
 */
public final class QueryRule implements Serializable
{
	private static final long serialVersionUID = 1L;
	public static final int ASC_ORDER = 101;
	public static final int DESC_ORDER = 102;
	public static final int LIKE = 1;
	public static final int IN = 2;
	public static final int NOTIN = 3;
	public static final int BETWEEN = 4;
	public static final int EQ = 5;
	public static final int NOTEQ = 6;
	public static final int GT = 7;
	public static final int GE = 8;
	public static final int LT = 9;
	public static final int LE = 10;
	public static final int ISNULL = 11;
	public static final int ISNOTNULL = 12;
	public static final int ISEMPTY = 13;
	public static final int ISNOTEMPTY = 14;
	public static final int AND = 201;
	public static final int OR = 202;
	private List<Rule> ruleList = new ArrayList<Rule>();
	private List<QueryRule> queryRuleList = new ArrayList<QueryRule>();
	private String propertyName;

	private QueryRule() {}

	private QueryRule(String propertyName) {
		this.propertyName = propertyName;
	}

	public static QueryRule getInstance() {
		return new QueryRule();
	}
	
	/**
	 * 添加升序规则
	 * @param propertyName
	 * @return
	 */
	public QueryRule addAscOrder(String propertyName) {
		this.ruleList.add(new Rule(ASC_ORDER, propertyName));
		return this;
	}

	/**
	 * 添加降序规则
	 * @param propertyName
	 * @return
	 */
	public QueryRule addDescOrder(String propertyName) {
		this.ruleList.add(new Rule(DESC_ORDER, propertyName));
		return this;
	}

	public QueryRule andIsNull(String propertyName) {
		this.ruleList.add(new Rule(ISNULL, propertyName).setAndOr(AND));
		return this;
	}

	public QueryRule andIsNotNull(String propertyName) {
		this.ruleList.add(new Rule(ISNOTNULL, propertyName).setAndOr(AND));
		return this;
	}

	public QueryRule andIsEmpty(String propertyName) {
		this.ruleList.add(new Rule(ISEMPTY, propertyName).setAndOr(AND));
		return this;
	}

	public QueryRule andIsNotEmpty(String propertyName) {
		this.ruleList.add(new Rule(ISNOTEMPTY, propertyName).setAndOr(AND));
		return this;
	}

	public QueryRule andLike(String propertyName, Object value) {
		this.ruleList.add(new Rule(LIKE, propertyName, new Object[] { value }).setAndOr(AND));
		return this;
	}

	public QueryRule andEqual(String propertyName, Object value) {
		this.ruleList.add(new Rule(EQ, propertyName, new Object[] { value }).setAndOr(AND));
		return this;
	}

	public QueryRule andBetween(String propertyName, Object... values) {
		this.ruleList.add(new Rule(BETWEEN, propertyName, values).setAndOr(AND));
		return this;
	}

	public QueryRule andIn(String propertyName, List<Object> values) {
		this.ruleList.add(new Rule(IN, propertyName, new Object[] { values }).setAndOr(AND));
		return this;
	}

	public QueryRule andIn(String propertyName, Object... values) {
		this.ruleList.add(new Rule(IN, propertyName, values).setAndOr(AND));
		return this;
	}
	
	public QueryRule andNotIn(String propertyName, List<Object> values) {
		this.ruleList.add(new Rule(NOTIN, propertyName, new Object[] { values }).setAndOr(AND));
		return this;
	}

	public QueryRule orNotIn(String propertyName, Object... values) {
		this.ruleList.add(new Rule(NOTIN, propertyName, values).setAndOr(OR));
		return this;
	}
	

	public QueryRule andNotEqual(String propertyName, Object value) {
		this.ruleList.add(new Rule(NOTEQ, propertyName, new Object[] { value }).setAndOr(AND));
		return this;
	}

	public QueryRule andGreaterThan(String propertyName, Object value) {
		this.ruleList.add(new Rule(GT, propertyName, new Object[] { value }).setAndOr(AND));
		return this;
	}

	public QueryRule andGreaterEqual(String propertyName, Object value) {
		this.ruleList.add(new Rule(GE, propertyName, new Object[] { value }).setAndOr(AND));
		return this;
	}

	public QueryRule andLessThan(String propertyName, Object value) {
		this.ruleList.add(new Rule(LT, propertyName, new Object[] { value }).setAndOr(AND));
		return this;
	}

	public QueryRule andLessEqual(String propertyName, Object value) {
		this.ruleList.add(new Rule(LE, propertyName, new Object[] { value }).setAndOr(AND));
		return this;
	}
	
	
	public QueryRule orIsNull(String propertyName) {
		this.ruleList.add(new Rule(ISNULL, propertyName).setAndOr(OR));
		return this;
	}

	public QueryRule orIsNotNull(String propertyName) {
		this.ruleList.add(new Rule(ISNOTNULL, propertyName).setAndOr(OR));
		return this;
	}

	public QueryRule orIsEmpty(String propertyName) {
		this.ruleList.add(new Rule(ISEMPTY, propertyName).setAndOr(OR));
		return this;
	}

	public QueryRule orIsNotEmpty(String propertyName) {
		this.ruleList.add(new Rule(ISNOTEMPTY, propertyName).setAndOr(OR));
		return this;
	}

	public QueryRule orLike(String propertyName, Object value) {
		this.ruleList.add(new Rule(LIKE, propertyName, new Object[] { value }).setAndOr(OR));
		return this;
	}

	public QueryRule orEqual(String propertyName, Object value) {
		this.ruleList.add(new Rule(EQ, propertyName, new Object[] { value }).setAndOr(OR));
		return this;
	}

	public QueryRule orBetween(String propertyName, Object... values) {
		this.ruleList.add(new Rule(BETWEEN, propertyName, values).setAndOr(OR));
		return this;
	}

	public QueryRule orIn(String propertyName, List<Object> values) {
		this.ruleList.add(new Rule(IN, propertyName, new Object[] { values }).setAndOr(OR));
		return this;
	}

	public QueryRule orIn(String propertyName, Object... values) {
		this.ruleList.add(new Rule(IN, propertyName, values).setAndOr(OR));
		return this;
	}

	public QueryRule orNotEqual(String propertyName, Object value) {
		this.ruleList.add(new Rule(NOTEQ, propertyName, new Object[] { value }).setAndOr(OR));
		return this;
	}

	public QueryRule orGreaterThan(String propertyName, Object value) {
		this.ruleList.add(new Rule(GT, propertyName, new Object[] { value }).setAndOr(OR));
		return this;
	}

	public QueryRule orGreaterEqual(String propertyName, Object value) {
		this.ruleList.add(new Rule(GE, propertyName, new Object[] { value }).setAndOr(OR));
		return this;
	}

	public QueryRule orLessThan(String propertyName, Object value) {
		this.ruleList.add(new Rule(LT, propertyName, new Object[] { value }).setAndOr(OR));
		return this;
	}

	public QueryRule orLessEqual(String propertyName, Object value) {
		this.ruleList.add(new Rule(LE, propertyName, new Object[] { value }).setAndOr(OR));
		return this;
	}
	

	public List<Rule> getRuleList() {
		return this.ruleList;
	}

	public List<QueryRule> getQueryRuleList() {
		return this.queryRuleList;
	}

	public String getPropertyName() {
		return this.propertyName;
	}

	protected class Rule implements Serializable {
		private static final long serialVersionUID = 1L;
		private int type;	//规则的类型
		private String property_name;
		private Object[] values;
		private int andOr = AND;

		public Rule(int paramInt, String paramString) {
			this.property_name = paramString;
			this.type = paramInt;
		}

		public Rule(int paramInt, String paramString,
				Object[] paramArrayOfObject) {
			this.property_name = paramString;
			this.values = paramArrayOfObject;
			this.type = paramInt;
		}
		
		public Rule setAndOr(int andOr){
			this.andOr = andOr;
			return this;
		}
		
		public int getAndOr(){
			return this.andOr;
		}

		public Object[] getValues() {
			return this.values;
		}

		public int getType() {
			return this.type;
		}

		public String getPropertyName() {
			return this.property_name;
		}
	}
}
复制代码


import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.lang.ArrayUtils;

import com.gupaoedu.vip.pattern.builder.sql.QueryRule.Rule;
import org.apache.commons.lang.StringUtils;


/**
 * 根据QueryRule自动构建sql语句
 * @author 
 *
 */
public class QueryRuleSqlBuilder {
	private int CURR_INDEX = 0; //记录参数所在的位置
	private List<String> properties; //保存列名列表
	private List<Object> values; //保存参数值列表
	private List<Order> orders; //保存排序规则列表
	
	private String whereSql = ""; 
	private String orderSql = "";
	private Object [] valueArr = new Object[]{};
	private Map<Object,Object> valueMap = new HashMap<Object,Object>();
	
	/**
	 * 或得查询条件
	 * @return
	 */
	private String getWhereSql(){
		return this.whereSql;
	}
	
	/**
	 * 获得排序条件
	 * @return
	 */
	private String getOrderSql(){
		return this.orderSql;
	}
	
	/**
	 * 获得参数值列表
	 * @return
	 */
	public Object [] getValues(){
		return this.valueArr;
	}
	
	/**
	 * 获取参数列表
	 * @return
	 */
	private Map<Object,Object> getValueMap(){
		return this.valueMap;
	}
	
	/**
	 * 创建SQL构造器
	 * @param queryRule
	 */
	public QueryRuleSqlBuilder(QueryRule queryRule) {
		CURR_INDEX = 0;
		properties = new ArrayList<String>();
		values = new ArrayList<Object>();
		orders = new ArrayList<Order>();
		for (QueryRule.Rule rule : queryRule.getRuleList()) {
			switch (rule.getType()) {
			case QueryRule.BETWEEN:
				processBetween(rule);
				break;
			case QueryRule.EQ:
				processEqual(rule);
				break;
			case QueryRule.LIKE:
				processLike(rule);
				break;
			case QueryRule.NOTEQ:
				processNotEqual(rule);
				break;
			case QueryRule.GT:
				processGreaterThen(rule);
				break;
			case QueryRule.GE:
				processGreaterEqual(rule);
				break;
			case QueryRule.LT:
				processLessThen(rule);
				break;
			case QueryRule.LE:
				processLessEqual(rule);
				break;
			case QueryRule.IN:
				processIN(rule);
				break;
			case QueryRule.NOTIN:
				processNotIN(rule);
				break;
			case QueryRule.ISNULL:
				processIsNull(rule);
				break;
			case QueryRule.ISNOTNULL:
				processIsNotNull(rule);
				break;
			case QueryRule.ISEMPTY:
				processIsEmpty(rule);
				break;
			case QueryRule.ISNOTEMPTY:
				processIsNotEmpty(rule);
				break;
			case QueryRule.ASC_ORDER:
				processOrder(rule);
				break;
			case QueryRule.DESC_ORDER:
				processOrder(rule);
				break;
			default:
				throw new IllegalArgumentException("type " + rule.getType() + " not supported.");
			}
		}
		//拼装where语句
		appendWhereSql();
		//拼装排序语句
		appendOrderSql();
		//拼装参数值
		appendValues();
	}
	
	/**
	 * 去掉order
	 * 
	 * @param sql
	 * @return
	 */
	private String removeOrders(String sql) {
		Pattern p = Pattern.compile("order\\s*by[\\w|\\W|\\s|\\S]*", Pattern.CASE_INSENSITIVE);
		Matcher m = p.matcher(sql);
		StringBuffer sb = new StringBuffer();
		while (m.find()) {
			m.appendReplacement(sb, "");
		}
		m.appendTail(sb);
		return sb.toString();
	}
	
	/**
	 * 去掉select
	 * 
	 * @param sql
	 * @return
	 */
	private String removeSelect(String sql) {
		if(sql.toLowerCase().matches("from\\s+")){
			int beginPos = sql.toLowerCase().indexOf("from");
			return sql.substring(beginPos);
		}else{
			return sql;
		}
	}
	
	/**
	 * 处理like
	 * @param rule
	 */
	private  void processLike(QueryRule.Rule rule) {
		if (ArrayUtils.isEmpty(rule.getValues())) {
			return;
		}
		Object obj = rule.getValues()[0];

		if (obj != null) {
			String value = obj.toString();
			if (!StringUtils.isEmpty(value)) {
				value = value.replace('*', '%');
				obj = value;
			}
		}
		add(rule.getAndOr(),rule.getPropertyName(),"like","%"+rule.getValues()[0]+"%");
	}

	/**
	 * 处理between
	 * @param rule
	 */
	private  void processBetween(QueryRule.Rule rule) {
		if ((ArrayUtils.isEmpty(rule.getValues()))
				|| (rule.getValues().length < 2)) {
			return;
		}
		add(rule.getAndOr(),rule.getPropertyName(),"","between",rule.getValues()[0],"and");
		add(0,"","","",rule.getValues()[1],"");
	}
	
	/**
	 * 处理 =
	 * @param rule
	 */
	private  void processEqual(QueryRule.Rule rule) {
		if (ArrayUtils.isEmpty(rule.getValues())) {
			return;
		}
		add(rule.getAndOr(),rule.getPropertyName(),"=",rule.getValues()[0]);
	}

	/**
	 * 处理 <>
	 * @param rule
	 */
	private  void processNotEqual(QueryRule.Rule rule) {
		if (ArrayUtils.isEmpty(rule.getValues())) {
			return;
		}
		add(rule.getAndOr(),rule.getPropertyName(),"<>",rule.getValues()[0]);
	}

	/**
	 * 处理 >
	 * @param rule
	 */
	private  void processGreaterThen(
			QueryRule.Rule rule) {
		if (ArrayUtils.isEmpty(rule.getValues())) {
			return;
		}
		add(rule.getAndOr(),rule.getPropertyName(),">",rule.getValues()[0]);
	}

	/**
	 * 处理>=
	 * @param rule
	 */
	private  void processGreaterEqual(
			QueryRule.Rule rule) {
		if (ArrayUtils.isEmpty(rule.getValues())) {
			return;
		}
		add(rule.getAndOr(),rule.getPropertyName(),">=",rule.getValues()[0]);
	}

	/**
	 * 处理<
	 * @param rule
	 */
	private  void processLessThen(QueryRule.Rule rule) {
		if (ArrayUtils.isEmpty(rule.getValues())) {
			return;
		}
		add(rule.getAndOr(),rule.getPropertyName(),"<",rule.getValues()[0]);
	}

	/**
	 * 处理<=
	 * @param rule
	 */
	private  void processLessEqual(
			QueryRule.Rule rule) {
		if (ArrayUtils.isEmpty(rule.getValues())) {
			return;
		}
		add(rule.getAndOr(),rule.getPropertyName(),"<=",rule.getValues()[0]);
	}

	/**
	 * 处理  is null
	 * @param rule
	 */
	private  void processIsNull(QueryRule.Rule rule) {
		add(rule.getAndOr(),rule.getPropertyName(),"is null",null);
	}

	/**
	 * 处理 is not null
	 * @param rule
	 */
	private  void processIsNotNull(QueryRule.Rule rule) {
		add(rule.getAndOr(),rule.getPropertyName(),"is not null",null);
	}

	/**
	 * 处理  <>''
	 * @param rule
	 */
	private  void processIsNotEmpty(QueryRule.Rule rule) {
		add(rule.getAndOr(),rule.getPropertyName(),"<>","''");
	}

	/**
	 * 处理 =''
	 * @param rule
	 */
	private  void processIsEmpty(QueryRule.Rule rule) {
		add(rule.getAndOr(),rule.getPropertyName(),"=","''");
	}

	
	/**
	 * 处理in和not in
	 * @param rule
	 * @param name
	 */
	private void inAndNotIn(QueryRule.Rule rule,String name){
		if (ArrayUtils.isEmpty(rule.getValues())) {
			return;
		}
		if ((rule.getValues().length == 1) && (rule.getValues()[0] != null)
				&& (rule.getValues()[0] instanceof List)) {
			List<Object> list = (List) rule.getValues()[0];
			
			if ((list != null) && (list.size() > 0)){
				for (int i = 0; i < list.size(); i++) {
					if(i == 0 && i == list.size() - 1){
						add(rule.getAndOr(),rule.getPropertyName(),"",name + " (",list.get(i),")");
					}else if(i == 0 && i < list.size() - 1){
						add(rule.getAndOr(),rule.getPropertyName(),"",name + " (",list.get(i),"");
					}
					if(i > 0 && i < list.size() - 1){
						add(0,"",",","",list.get(i),"");
					}
					if(i == list.size() - 1 && i != 0){
						add(0,"",",","",list.get(i),")");
					}
				}
			}
		} else {
			Object[] list =  rule.getValues();
			for (int i = 0; i < list.length; i++) {
				if(i == 0 && i == list.length - 1){
					add(rule.getAndOr(),rule.getPropertyName(),"",name + " (",list[i],")");
				}else if(i == 0 && i < list.length - 1){
					add(rule.getAndOr(),rule.getPropertyName(),"",name + " (",list[i],"");
				}
				if(i > 0 && i < list.length - 1){
					add(0,"",",","",list[i],"");
				}
				if(i == list.length - 1 && i != 0){
					add(0,"",",","",list[i],")");
				}
			}
		}
	}
	
	/**
	 * 处理 not in
	 * @param rule
	 */
	private void processNotIN(QueryRule.Rule rule){
		inAndNotIn(rule,"not in");
	}
	
	/**
	 * 处理 in
	 * @param rule
	 */
	private  void processIN(QueryRule.Rule rule) {
		inAndNotIn(rule,"in");
	}
	
	/**
	 * 处理 order by
	 * @param rule 查询规则
	 */
	private void processOrder(Rule rule) {
		switch (rule.getType()) {
		case QueryRule.ASC_ORDER:
			// propertyName非空
			if (!StringUtils.isEmpty(rule.getPropertyName())) {
				orders.add(Order.asc(rule.getPropertyName()));
			}
			break;
		case QueryRule.DESC_ORDER:
			// propertyName非空
			if (!StringUtils.isEmpty(rule.getPropertyName())) {
				orders.add(Order.desc(rule.getPropertyName()));
			}
			break;
		default:
			break;
		}
	}
	
	
	/**
	 * 加入到sql查询规则队列
	 * @param andOr and 或者 or
	 * @param key 列名
	 * @param split 列名与值之间的间隔
	 * @param value 值
	 */
	private  void add(int andOr,String key,String split ,Object value){
		add(andOr,key,split,"",value,"");
	}
	
	/**
	 * 加入到sql查询规则队列
	 * @param andOr and 或则 or
	 * @param key 列名
	 * @param split 列名与值之间的间隔
	 * @param prefix 值前缀
	 * @param value 值
	 * @param suffix 值后缀
	 */
	private  void add(int andOr,String key,String split ,String prefix,Object value,String  suffix){
		String andOrStr = (0 == andOr ? "" :(QueryRule.AND == andOr ? " and " : " or "));  
		properties.add(CURR_INDEX, andOrStr + key + " " + split + prefix + (null != value ? " ? " : " ") + suffix);
		if(null != value){
			values.add(CURR_INDEX,value);
			CURR_INDEX ++;
		}
	}
	
	
	/**
	 * 拼装 where 语句
	 */
	private void appendWhereSql(){
		StringBuffer whereSql = new StringBuffer();
		for (String p : properties) {
			whereSql.append(p);
		}
		this.whereSql = removeSelect(removeOrders(whereSql.toString()));
	}
	
	/**
	 * 拼装排序语句
	 */
	private void appendOrderSql(){
		StringBuffer orderSql = new StringBuffer();
		for (int i = 0 ; i < orders.size(); i ++) {
			if(i > 0 && i < orders.size()){
				orderSql.append(",");
			}
			orderSql.append(orders.get(i).toString());
		}
		this.orderSql = removeSelect(removeOrders(orderSql.toString()));
	}
	
	/**
	 * 拼装参数值
	 */
	private void appendValues(){
		Object [] val = new Object[values.size()];
		for (int i = 0; i < values.size(); i ++) {
			val[i] = values.get(i);
			valueMap.put(i, values.get(i));
		}
		this.valueArr = val;
	}

	public String builder(String tableName){
		String ws = removeFirstAnd(this.getWhereSql());
		String whereSql = ("".equals(ws) ? ws : (" where " + ws));
		String sql = "select * from " + tableName + whereSql;
		Object [] values = this.getValues();
		String orderSql = this.getOrderSql();
		orderSql = (StringUtils.isEmpty(orderSql) ? " " : (" order by " + orderSql));
		sql += orderSql;
		return sql;
	}


	private String removeFirstAnd(String sql){
		if(StringUtils.isEmpty(sql)){return sql;}
		return sql.trim().toLowerCase().replaceAll("^\\s*and", "") + " ";
	}

}
复制代码

/**
 * sql排序组件
 * @author 
 */
public class Order {
	private boolean ascending; //升序还是降序
	private String propertyName; //哪个字段升序，哪个字段降序
	
	public String toString() {
		return propertyName + ' ' + (ascending ? "asc" : "desc");
	}

	/**
	 * Constructor for Order.
	 */
	protected Order(String propertyName, boolean ascending) {
		this.propertyName = propertyName;
		this.ascending = ascending;
	}

	/**
	 * Ascending order
	 *
	 * @param propertyName
	 * @return Order
	 */
	public static Order asc(String propertyName) {
		return new Order(propertyName, true);
	}

	/**
	 * Descending order
	 *
	 * @param propertyName
	 * @return Order
	 */
	public static Order desc(String propertyName) {
		return new Order(propertyName, false);
	}

}
复制代码

import javax.management.Query;
import java.util.Arrays;


public class Test {
    public static void main(String[] args) {
        QueryRule queryRule = QueryRule.getInstance();
        queryRule.addAscOrder("age");
        queryRule.andEqual("addr","Changsha");
        queryRule.andLike("name","Tom");
        QueryRuleSqlBuilder builder = new QueryRuleSqlBuilder(queryRule);

        System.out.println(builder.builder("t_member"));

        System.out.println("Params: " + Arrays.toString(builder.getValues()));

    }
}
复制代码

文章版权归作者所有，未经允许请勿转载。

THE END

阅读