jqGrid与Struts2的结合应用（五） —— 结合Action类进行数据查询
不过继续深入学习还是碰到了问题，
多条件查询出问题了。
症状如下：
1、没有比较操作符
2、代码方面也是自己瞎凑的求大侠们来帮忙
Criterion.java ，不知道为什么没有实现官方的Criterion接口。因为不懂，在Action.java里用离线连接的时候必须要转换成官方的类所以我做了实现官方类。
package cn.dao.impl;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.hibernate.Criteria;
import org.hibernate.HibernateException;
import org.hibernate.criterion.CriteriaQuery;
import org.hibernate.engine.TypedValue;
public class Criterion implements org.hibernate.criterion.Criterion {
/**
*
*/
private static final long serialVersionUID = 1L;
public static enum CriterionType {
EQUAL, LIKE, COMPARE, NOT_LIKE
}
public static enum CompareType {
GT, GTE, LT, LTE, EQ, NE
}
private CriterionType criterionType;
private String tableName;
private String field;
private Object value;
// 将Criteria转换为SQL条件语句
public static String convertToSql(List<Criterion> criteria) {
String criteriaString = "";
StringBuilder sb = new StringBuilder();
for (Criterion criterion : criteria) {
String prefix = criterion.getFieldPrefix();
switch (criterion.getCriterionType()) {
case EQUAL:
sb.append(prefix + criterion.getField() + "=? and ");
break;
case LIKE:
sb.append(prefix + criterion.getField() + " like ? and ");
break;
case NOT_LIKE:
sb.append(prefix + criterion.getField() + " not like ? and ");
break;
case COMPARE:
CompareType compareType = ((CompareCriterion) criterion)
.getCompareType();
switch (compareType) {
case EQ:
sb.append(prefix + criterion.getField() + "=? and ");
break;
case NE:
sb.append(prefix + criterion.getField() + "<>? and ");
break;
case GT:
sb.append(prefix + criterion.getField() + ">? and ");
break;
case GTE:
sb.append(prefix + criterion.getField() + ">=? and ");
break;
case LT:
sb.append(prefix + criterion.getField() + "<? and ");
break;
case LTE:
sb.append(prefix + criterion.getField() + "<=? and ");
break;
}
break;
}
}
int i = -1;
if ((i = sb.lastIndexOf(" and ")) != -1) {
criteriaString = sb.substring(0, i);
}
return criteriaString;
}
// 将Criteria各条件的值转换为List<Object>
public static List<Object> getCriteriaValues(List<Criterion> criteria) {
List<Object> criteriaValues = criteria.isEmpty() ? Collections
.emptyList() : new ArrayList<Object>();
for (Criterion criterion : criteria) {
criteriaValues.add(criterion.getValue());
}
return criteriaValues;
}
public CriterionType getCriterionType() {
return criterionType;
}
public void setCriterionType(CriterionType criterionType) {
this.criterionType = criterionType;
}
public String getField() {
return field;
}
public void setField(String field) {
this.field = field;
}
public Object getValue() {
return value;
}
public void setValue(Object value) {
this.value = value;
}
public static Criterion getCompareCriterion(CompareType compareType,
String field, Object value, String tableName) {
CompareCriterion compareCriterion = new CompareCriterion();
compareCriterion.setCriterionType(CriterionType.COMPARE);
compareCriterion.setCompareType(compareType);
compareCriterion.setField(field);
compareCriterion.setValue(value);
compareCriterion.setTableName(tableName);
return compareCriterion;
}
public static Criterion getLikeCriterion(String field, Object value,
String tableName) {
LikeCriterion likeCriterion = new LikeCriterion();
likeCriterion.setCriterionType(CriterionType.LIKE);
likeCriterion.setField(field);
likeCriterion.setValue(value);
likeCriterion.setTableName(tableName);
return likeCriterion;
}
public static Criterion getNotLikeCriterion(String field, Object value,
String tableName) {
NotLikeCriterion notLikeCriterion = new NotLikeCriterion();
notLikeCriterion.setCriterionType(CriterionType.NOT_LIKE);
notLikeCriterion.setField(field);
notLikeCriterion.setValue(value);
notLikeCriterion.setTableName(tableName);
return notLikeCriterion;
}
public static Criterion getEqualCriterion(String field, Object value,
String tableName) {
EqualCriterion equalCriterion = new EqualCriterion();
equalCriterion.setCriterionType(CriterionType.EQUAL);
equalCriterion.setField(field);
equalCriterion.setValue(value);
equalCriterion.setTableName(tableName);
return equalCriterion;
}
public static class LikeCriterion extends Criterion {
}
public static class NotLikeCriterion extends Criterion {
}
public static class EqualCriterion extends Criterion {
}
public static class CompareCriterion extends Criterion {
private CompareType compareType;
public CompareType getCompareType() {
return compareType;
}
public void setCompareType(CompareType compareType) {
this.compareType = compareType;
}
}
public String getTableName() {
return tableName;
}
public void setTableName(String tableName) {
this.tableName = tableName;
}
public String getFieldPrefix() {
return (tableName == null || tableName.length() == 0) ? "" : tableName
+ ".";
}
@Override
public TypedValue[] getTypedValues(Criteria arg0, CriteriaQuery arg1)
throws HibernateException {
// TODO Auto-generated method stub
return null;
}
@Override
public String toSqlString(Criteria arg0, CriteriaQuery arg1)
throws HibernateException {
// TODO Auto-generated method stub
return null;
}
}
daobean.java
@SuppressWarnings("unchecked")
public List detachedCriteria(final DetachedCriteria detachedCriteria)
{
return this.getHibernateTemplate().execute(new HibernateCallback()
{
public Object doInHibernate(Session session)
throws HibernateException, SQLException {
//构造Criteria，detachedCriteria与session关联下
Criteria criteria = detachedCriteria.getExecutableCriteria(session);
return criteria.list();
}
});
}
action.java
@Override
public List<Roomusage> listResults(List<Criterion> criteria, int from,
int length) {
DetachedCriteria detachedCriteria = DetachedCriteria.forClass(Roomusage.class);
for(Criterion criteria1:criteria){
detachedCriteria.add(criteria1);
}
List<Roomusage> results = roomusageService.detachedCriteria(detachedCriteria,from,length);
return results;
}
service.java
实在还没明白悟透，这边传入的两个参数也被我直接作废了.....
@Transactional(propagation=Propagation.SUPPORTS,readOnly=true)
public List detachedCriteria(final DetachedCriteria detachedCriteria,int from,int length)
{
return roomusageDao.detachedCriteria(detachedCriteria);
}
当前状态，多条件查询没用。
网上找了Demo都没配置运行起来......可能是java版本问题 找的貌似1.5的
求大侠帮忙。
先躺个沙发来着。
顶个
看样子只好自力更生了
终于有眉目了，要是谁有问题可以看下