Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Jr17pu(t
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 2IjqTL
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 tB(Q-c
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分页支持类: u"T5m
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java代码: AX'(xb,
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package com.javaeye.common.util; 0?p_|X'_
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import java.util.List; hNx`=D9[7
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publicclass PaginationSupport { pbqa
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publicfinalstaticint PAGESIZE = 30; &}T`[ d_Z
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privateint pageSize = PAGESIZE; ?\vJ8H[bD
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privateList items; )_j.0a
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privateint totalCount; Eq.c;3
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privateint[] indexes = newint[0]; I">z#@CT
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privateint startIndex = 0; 5 yA^ n6
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public PaginationSupport(List items, int EiJSLL
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totalCount){ P45q}v
setPageSize(PAGESIZE); ke3=s
setTotalCount(totalCount); *EV] 8
setItems(items); _^a.kF
setStartIndex(0); h@W}xT
} |d%Dw^
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public PaginationSupport(List items, int =z=Guvcn`
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totalCount, int startIndex){ tOspDPSXX
setPageSize(PAGESIZE); $u3N ',&
setTotalCount(totalCount); "r"Y9KODm
setItems(items); ^kt"n(P5
setStartIndex(startIndex); v11mu2
} .f jM9G#
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public PaginationSupport(List items, int K]
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totalCount, int pageSize, int startIndex){ mD )Nh
setPageSize(pageSize); 8<]> q
setTotalCount(totalCount); a?JU(
setItems(items); %{HqF>=~
setStartIndex(startIndex); /@wm?ft6Gk
} /au\OBUge
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publicList getItems(){ hlUF9}
return items; Nju7!yVM_
} QT|m N
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publicvoid setItems(List items){ &UzZE17R
this.items = items; ! prU!5-
} dvL '>'g
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publicint getPageSize(){ DJ<c
return pageSize; zZf#E@=$|
} }(hE{((o
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publicvoid setPageSize(int pageSize){ ^ g4)aaBZ
this.pageSize = pageSize; Y^6=_^
} t: [[5];E
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publicint getTotalCount(){ Q]|+Y0y}X
return totalCount; zM@iG]?kc
} 2<988F
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publicvoid setTotalCount(int totalCount){ x%(!+
if(totalCount > 0){ ikxSWO_Y=
this.totalCount = totalCount; hG
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int count = totalCount / |Pj _L`G
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pageSize;
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if(totalCount % pageSize > 0) Jhj]rsGk
count++; H/L3w|2+
indexes = newint[count]; k~q[qKb8y:
for(int i = 0; i < count; i++){ [j![R
indexes = pageSize * 94a_ W9
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} +QHhAA$
}else{ u{3KV6MS
this.totalCount = 0; S((8DSt*
} He]F~GXP
} Mq7|37(N[
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publicint[] getIndexes(){ f
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return indexes; fe0 Y^vW
} |QzPY8B9O
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publicvoid setIndexes(int[] indexes){ T4f:0r;^f*
this.indexes = indexes; mWGT
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} ';lO[B
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publicint getStartIndex(){ QU#/(N(U#T
return startIndex; '8Gw{&&
} snK9']WXo
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publicvoid setStartIndex(int startIndex){ |j!D _j#U
if(totalCount <= 0) 4B> l|%
this.startIndex = 0; L`Ic0}|lzy
elseif(startIndex >= totalCount) Z7f~|}
this.startIndex = indexes K3Xy%pqR#
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[indexes.length - 1]; %(e=Q^=
elseif(startIndex < 0) _ Po9pZ
this.startIndex = 0; :heJ5*!,
else{ A%2!Hr
this.startIndex = indexes l%U9g
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[startIndex / pageSize]; y7w>/7q
} ^{Vm,nAQqs
} Zg'[.wov
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publicint getNextIndex(){ <B
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int nextIndex = getStartIndex() + rcbixOT
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pageSize; MUo?ajbqOd
if(nextIndex >= totalCount) ~ACB#D%
return getStartIndex(); >Y,7>ahyt
else Vnl~AQfk|
return nextIndex; #2MwmIeA
} h\dIp`H
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publicint getPreviousIndex(){
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int previousIndex = getStartIndex() - 6%'{Cq1DE
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pageSize; K)v(Z"
if(previousIndex < 0) '0=U+Egp
return0; >2|#b
else [L\w]6
return previousIndex; 0hv[Ff
} !kIw835U
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} :C&?(HJ&r
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抽象业务类 tb
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java代码: *dQRs6
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/** J^XH^`'
* Created on 2005-7-12 CVUDN2
*/ A1@-;/H3
package com.javaeye.common.business; sDF J
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import java.io.Serializable; 226s:\d
import java.util.List; \x+DEy'4;5
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import org.hibernate.Criteria; (r|T&'yK
import org.hibernate.HibernateException; 7q?YdAUz
import org.hibernate.Session; Uyh
import org.hibernate.criterion.DetachedCriteria; ^U =`Rx
import org.hibernate.criterion.Projections; !Q#b4 f
import <hea%6
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org.springframework.orm.hibernate3.HibernateCallback; WLpn,8qsY
import wiVQMgi`
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org.springframework.orm.hibernate3.support.HibernateDaoS d.+vjMI
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upport; JC#@sJ4az)
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import com.javaeye.common.util.PaginationSupport; U%4g:s
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public abstract class AbstractManager extends X1-s,[j'
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HibernateDaoSupport { \w:u&6,0O
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privateboolean cacheQueries = false; j@ "`!uPz
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privateString queryCacheRegion; J.&q[
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publicvoid setCacheQueries(boolean Y1~SGg7(@
{,
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cacheQueries){ 8 N` $7^^
this.cacheQueries = cacheQueries; *"5a5.`%,
} `%Ghtm *
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publicvoid setQueryCacheRegion(String MT5A%|H e
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queryCacheRegion){ xo%iL
this.queryCacheRegion = PHXP1)^}S
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queryCacheRegion; v Y\O=TZT
} |x4yPYBL
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publicvoid save(finalObject entity){ Po_OQJ:bd
getHibernateTemplate().save(entity); So^`L s;S
} =4D_-Q
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publicvoid persist(finalObject entity){ Jv<)/Km`
getHibernateTemplate().save(entity); Id*^H:]C#
} >(CoXSV5
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publicvoid update(finalObject entity){ pd1m/:
getHibernateTemplate().update(entity); Psa8OJan
} E
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publicvoid delete(finalObject entity){ U{_s1
getHibernateTemplate().delete(entity); 7`/qL "
} CJOl|"UyJ
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publicObject load(finalClass entity, `|w#K28t"
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finalSerializable id){ of`]LU:
return getHibernateTemplate().load "6dbRo5%
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(entity, id); @e,Zmx
} O}-7 V5
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publicObject get(finalClass entity, Mh|`XO.5I
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finalSerializable id){ T/;hIX:R
return getHibernateTemplate().get $te,\$&}
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(entity, id); 6y_Z'@L
} [J`G`s!
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publicList findAll(finalClass entity){ cQ41NX@I
return getHibernateTemplate().find("from orHD3T%&
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" + entity.getName()); j*u9+.
} ewG21 q$
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publicList findByNamedQuery(finalString UK>=y_FYO
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namedQuery){ Nj_sU0Dt
return getHibernateTemplate C<t>m_t9
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().findByNamedQuery(namedQuery); ,rI
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} A4FDR#
} XU:DE
publicList findByNamedQuery(finalString query, kV3j}C"
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finalObject parameter){ $tHwJ!<$&
return getHibernateTemplate &U*J{OP|
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().findByNamedQuery(query, parameter); 8VmN?"5v
} 1!wEXH(
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publicList findByNamedQuery(finalString query, Oc9>F\]_m
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finalObject[] parameters){ Sc$wR{W<:
return getHibernateTemplate DB%AO:8
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().findByNamedQuery(query, parameters); '?gIcWM
} w%dIe!sV
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publicList find(finalString query){ VQ<i$ I
return getHibernateTemplate().find TDE1z>h+"
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(query); 6xIYg ^
} _`{{39 F
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publicList find(finalString query, finalObject fsc~$^.~\
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parameter){ wV&f|JO0+
return getHibernateTemplate().find doO
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(query, parameter); y6Epi|8
} !K3cf]2UD
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public PaginationSupport findPageByCriteria m'(;uR`
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(final DetachedCriteria detachedCriteria){ KBRg95E~]l
return findPageByCriteria yXV|4
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 5[2.5/
} 50GYL5)q
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public PaginationSupport findPageByCriteria e_k
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(final DetachedCriteria detachedCriteria, finalint 9>&tMq
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startIndex){ XVDd1#h
return findPageByCriteria +%qSB9_>N{
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(detachedCriteria, PaginationSupport.PAGESIZE, rKQASRF5*
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startIndex); c`i=(D<
} ?)[zLnxc&
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public PaginationSupport findPageByCriteria LbX6p
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(final DetachedCriteria detachedCriteria, finalint ;IuK2iDt<
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pageSize, "-QRkif
finalint startIndex){ >6[ X }
return(PaginationSupport) q _]
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getHibernateTemplate().execute(new HibernateCallback(){ y+";
publicObject doInHibernate TG63
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(Session session)throws HibernateException { 'ztL3(|X6
Criteria criteria = Vo 6y8@\
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detachedCriteria.getExecutableCriteria(session); \l]pe|0EW
int totalCount = 'y6!%k*
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((Integer) criteria.setProjection(Projections.rowCount Y%)h)El
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()).uniqueResult()).intValue(); 9Z0CF~Y5
criteria.setProjection XiRT|%j
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(null); ;o)=XEh8P
List items = sUbz)BS#.
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criteria.setFirstResult(startIndex).setMaxResults (~7m"?
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(pageSize).list(); P~\a)Szy
PaginationSupport ps = WS1&3mOd
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new PaginationSupport(items, totalCount, pageSize, G/fP(o-Wd
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startIndex); rv,NQZ
return ps; 6MQs \ J6.
} 1<W4>~,wj
}, true); rwL=R,
} %jZp9}h
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public List findAllByCriteria(final
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DetachedCriteria detachedCriteria){ hY.e [+
return(List) getHibernateTemplate jSie&V@ px
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().execute(new HibernateCallback(){ xTJSr2f
publicObject doInHibernate #a(%(k S
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(Session session)throws HibernateException { #h gmUa
Criteria criteria = H~?*KcZ 0\
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detachedCriteria.getExecutableCriteria(session); 29a_ZU7e6
return criteria.list(); hJw
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} FQk_#BkK
}, true); Mhb '^\px
} %tzN@
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public int getCountByCriteria(final >'} Y1_S5
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DetachedCriteria detachedCriteria){ T_@[k
Integer count = (Integer) ;wJ7oj<
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getHibernateTemplate().execute(new HibernateCallback(){ #~H%[s a
publicObject doInHibernate Uz6{>OCvk|
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(Session session)throws HibernateException { xb =8t!
Criteria criteria = 5JBB+g
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detachedCriteria.getExecutableCriteria(session); ]aC':55(
return %[]"QbF?
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criteria.setProjection(Projections.rowCount z(g%ue\
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()).uniqueResult(); SY%A"bC
} +{,N X
}, true); a>o"^%x
return count.intValue(); KTG:I@|C
} '}jf#C1$c
} BIxV|\k
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用户在web层构造查询条件detachedCriteria,和可选的 <i\UMrD]`:
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 42rj6m\
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PaginationSupport的实例ps。 ZYE' C
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ps.getItems()得到已分页好的结果集 &$mZ?%^C
ps.getIndexes()得到分页索引的数组 Op`I;Q
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ps.getTotalCount()得到总结果数 eWb0^8_
ps.getStartIndex()当前分页索引 ![*:.CW
ps.getNextIndex()下一页索引 8weSrm
ps.getPreviousIndex()上一页索引 o3Mf:;2c C
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 H@K#|A=a
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 =yl4zQmg$
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一下代码重构了。 EkN_8(w
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我把原本我的做法也提供出来供大家讨论吧: Y\.-v\uJu
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首先,为了实现分页查询,我封装了一个Page类: h/,R{A2mO
java代码: xDR9_
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/*Created on 2005-4-14*/ <^d!Vzr]
package org.flyware.util.page;
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/** _b>F#nD,'%
* @author Joa 0CT}DQ._^N
* AT"!{Y "H
*/ Vwjk[ DOL
publicclass Page { 9lKn%|=T
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/** imply if the page has previous page */ }$l8d/_$[
privateboolean hasPrePage; Ve)ClH/DW
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/** imply if the page has next page */ ?N:B
privateboolean hasNextPage; rvW!7-R
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/** the number of every page */ $30oc
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privateint everyPage; W7t
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/** the total page number */ *P`v^&
privateint totalPage; xdPcsox~
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/** the number of current page */ N1%p"(
privateint currentPage; f0vJm
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/** the begin index of the records by the current C@1CanL@3
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query */ m#JI!_~!
privateint beginIndex; g6WPPpqus
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/** The default constructor */ t#Th9G]1
public Page(){ te i`/
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} nP<S6:s:
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/** construct the page by everyPage q(78fZ *X
* @param everyPage _g[-=y{Bb
* */ |XRImeF'd
public Page(int everyPage){ -OrR $w|e
this.everyPage = everyPage; f-4.WW2FN
} $_sYfU9
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/** The whole constructor */ ?OE#q$ g
public Page(boolean hasPrePage, boolean hasNextPage, um7o !yg,
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)>\4ULR83
int everyPage, int totalPage, !DPF7x(-{
int currentPage, int beginIndex){ 61} i5o
this.hasPrePage = hasPrePage; /t*YDWLg
this.hasNextPage = hasNextPage; `z9J`r=I
this.everyPage = everyPage; C ZJV_0
this.totalPage = totalPage; .oEbEs
this.currentPage = currentPage; iRNLKi
this.beginIndex = beginIndex; `?"6l5d.]
} fxd0e;NAAh
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/** ;$7v%Ls=
* @return }x:0os
* Returns the beginIndex. KVN"XqE4
*/ [[WF0q
publicint getBeginIndex(){ !;v.>.lw
return beginIndex; OUI6
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} g\Ak;03n
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/** "k:=Y7Dx
* @param beginIndex F)SP aC4
* The beginIndex to set. ]3ifdGk
*/ aE)by-'
publicvoid setBeginIndex(int beginIndex){ T/l1qcf`wT
this.beginIndex = beginIndex; Lg4YED9#
} v*z(@<Y
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/** 0}]SUe^
* @return
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* Returns the currentPage. gzf-)J
*/ e"k/d<
publicint getCurrentPage(){ OX\$ nQ\o
return currentPage; 4r&f%caU
} oh~:,
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/** +Rwx%=
* @param currentPage wfR&li{
* The currentPage to set. or 2|O#=
*/ )K;]y-Us[
publicvoid setCurrentPage(int currentPage){ kccWoU,
this.currentPage = currentPage; Y/fJQ6DY
} HbM0TXo
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/** xq[Yg15d%
* @return fPqr6OYz
* Returns the everyPage. Qhn;`9+L
*/ fvqd'2 t
publicint getEveryPage(){ T2=HG Z
return everyPage; s_[VHPN
} lr~0pL
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/** N|K4{Frm
* @param everyPage L(G92,.
* The everyPage to set. 8Lz]Z
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*/ B{MaMf)
publicvoid setEveryPage(int everyPage){ V'pqxjfd
this.everyPage = everyPage; jVWK0Zba
} qf#)lyr<D6
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/** tg\|?
* @return 2eb1lJdS
* Returns the hasNextPage. 3<:jx~y>
*/ eSfnB_@x2
publicboolean getHasNextPage(){ Y@uh[aS!
return hasNextPage; 4w93}t.z
} Z[?mc|*x
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/** h4)Bs\==mT
* @param hasNextPage [XR$F@o
* The hasNextPage to set. :TalW~r|
*/ np9dM
publicvoid setHasNextPage(boolean hasNextPage){ MYdO jcN
this.hasNextPage = hasNextPage; `<frgXu64
} [f/I2
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/** =&nW~<- v
* @return ,Nm$i"Lg
* Returns the hasPrePage. ZDt?j
*/ ,$lemH1d
publicboolean getHasPrePage(){ i=S~(gp
return hasPrePage; vB0RKk}d5
} L] %l51U
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/** 646JDX[o
* @param hasPrePage vB'>[jvA|
* The hasPrePage to set. 6 %Mt
*/ 12UD19!
publicvoid setHasPrePage(boolean hasPrePage){ Cu;5RSr2Z
this.hasPrePage = hasPrePage; v,@F|c?_S
} ?-)I+EAnE
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/** jgv`>o%<W
* @return Returns the totalPage. >ut" OL9J
* }baR5v
*/ UL$}{2N,_
publicint getTotalPage(){ j<<3Pr
return totalPage; `G9 l
} 5GzFoy)j>
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/** LeOP;#
* @param totalPage zp}eLm:=d
* The totalPage to set. [iP#VM-N
*/ ;&b.T}Nf06
publicvoid setTotalPage(int totalPage){ $g0+,ll[6
this.totalPage = totalPage; ]=pR
} /YAJbr
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} w;6bD'.>;
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 SRIA*M.B}
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个PageUtil,负责对Page对象进行构造: kYzKU2T\W
java代码: "Jq8?FoT
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/*Created on 2005-4-14*/ W,5Hx1z R
package org.flyware.util.page; W !w, f;
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import org.apache.commons.logging.Log; EOj"V'!
import org.apache.commons.logging.LogFactory; b?X.U}62_
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/** Fb`a~c~s
* @author Joa <7SpEVQ
* t_^X$pL
*/ Fb22p6r
publicclass PageUtil { )SF}2?7e
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privatestaticfinal Log logger = LogFactory.getLog Hb} X-6N
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(PageUtil.class); Dl(3wgA
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/** fWfk[(M'9
* Use the origin page to create a new page 2WX7nK;I
* @param page nRL. ppUI
* @param totalRecords x+ncc_2n&D
* @return M5nWVK7c
*/ )c n+1R
publicstatic Page createPage(Page page, int (wIzat
)a9 ]US^
totalRecords){ >(uZtYM\j
return createPage(page.getEveryPage(), y&}E~5O
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page.getCurrentPage(), totalRecords); Vtc36-\1*
} * _a@z1
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/** f=C ,e/sw
* the basic page utils not including exception eAv4FA4g
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handler |(5W86C,ju
* @param everyPage kpL@P oQ/r
* @param currentPage FuI73
* @param totalRecords \%PaceH
* @return page 1XM^8 .;
*/ ku$$ 1xq
publicstatic Page createPage(int everyPage, int Ya>oCr}K
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currentPage, int totalRecords){ 2
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everyPage = getEveryPage(everyPage); 1)
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currentPage = getCurrentPage(currentPage); BdlVabQyKW
int beginIndex = getBeginIndex(everyPage, 7K)6^r^
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currentPage); ?]D"k4
int totalPage = getTotalPage(everyPage, W;bu2ym&Q
3)-/`iy#
totalRecords); j83p)ido
boolean hasNextPage = hasNextPage(currentPage, I}Nd$P)>
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totalPage); hX`}Q4(k
boolean hasPrePage = hasPrePage(currentPage); C<KrMRWh^
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returnnew Page(hasPrePage, hasNextPage, %K(<$!
everyPage, totalPage, pw7[y^[Qg
currentPage, 5>BK%`
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beginIndex); PV|uPuz
} ^Ge+~o?x
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privatestaticint getEveryPage(int everyPage){ :'#TCDlOb
return everyPage == 0 ? 10 : everyPage; TXe$<4"
} XsnF~)YW
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privatestaticint getCurrentPage(int currentPage){ J[f;Xlh
return currentPage == 0 ? 1 : currentPage; :0s]U_h
} ^G6RjJxqp8
9Xx's%U
privatestaticint getBeginIndex(int everyPage, int ()~pY!)1/
7S?4XyU/o
currentPage){ LpR3BP@At
return(currentPage - 1) * everyPage; `rf_7
} +$oF]OO
]\7]%(
privatestaticint getTotalPage(int everyPage, int z5)s/;Sc
^Z:~91Tv-_
totalRecords){ jDQZQ NS
int totalPage = 0; ^ f# FI&
-_`>j~
if(totalRecords % everyPage == 0) ,o)d3g-&g
totalPage = totalRecords / everyPage; %-d]X{J:
else 76u&EG%
totalPage = totalRecords / everyPage + 1 ; `uC@nJ
Pp )3(T:
return totalPage; ?O>V%@
} o6V}$wT3J
H^YSJ6
privatestaticboolean hasPrePage(int currentPage){ oWYmj=D~2z
return currentPage == 1 ? false : true; a'z)
} +nJUFc
:=J,z,H_U
privatestaticboolean hasNextPage(int currentPage, =$]uoA
)_U<7"~0l
int totalPage){ >nzdnF_&zW
return currentPage == totalPage || totalPage == xQUu|gtL4
!Q#{o^{Y~
0 ? false : true; Nm|!#(L
} `ho1nY$)CE
O%FPS=
S#+h$UVh
} *4V=z#
lV%N
hiQha5
V7/I>^X
aG^4BpIP
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 iezO9`
gG/!,Q.Qh
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 fMOU$0]$<
EW3(cQbK
做法如下: k1QpKn*
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 fl\ly`_
#-bA[eQV
的信息,和一个结果集List: TA{\PKA)
java代码: g1jTy7g?
~Q\3pI. |
7D<#(CE{
/*Created on 2005-6-13*/ ]MxC_V+P`
package com.adt.bo; {7)st
W
Z,=7Tu bR#
import java.util.List; Y 'ow
'#k0a,<N
import org.flyware.util.page.Page; |`cKD >
zzxGAVu
/** l,kUhZ@W
* @author Joa #FNcF>3>
*/ lyGhdgWc
publicclass Result { JYTP
2
Y./2Ely
private Page page; JfR%L q~
m}X`> aD/
private List content; 3\B>lKhQ
2RX!V@z.G
/** %@u;5qD&
* The default constructor Sv +IS
*/
OVV]x{
public Result(){ NgY=&W,
super(); ll C#1
} :53)Nv
jrS[f
/** IP(Vr7-v
* The constructor using fields )gMG#>up@
* $g
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* @param page -:na:Vsi
* @param content PbmDNKEh{
*/ S;)w.
public Result(Page page, List content){ v&=gF/$
this.page = page; o|$AyS{1
this.content = content; :$n=$C-wp
} #E&80#Z5
{j7uv"|X7
/** CY"/uSB
* @return Returns the content. ~x|F)~:0=
*/ uH(f$A
publicList getContent(){ s{$(*_
return content; @w?P7P<O`
} }yz (xH
Jl&-,Vjb
/** Dp':oJC
* @return Returns the page. 2n|K5FR()
*/ !Ze5)g%H
public Page getPage(){ 4 XAQVq5
return page; sashzVwJ-=
} NB8/g0:=n&
1 A\OC
/** H(Z88.OM
* @param content MerFZd 1
* The content to set. Gy6l<:;
*/ } x2DT8u
public void setContent(List content){ fc
|GArL#}
this.content = content; @CT;g\4
} FGoy8+nB1M
_iir<}
/** zlEX+=3
* @param page v^1pN>#%g
* The page to set. BDjn
!3
*/ 0DJ+I
publicvoid setPage(Page page){ {PVW D7
this.page = page; 4/wa+Y+=vt
} ,d {"m)r<
} iy%ZQ[Un
IkGfnXJ
`a2n:F
J{k79v
o*o/q],C9-
2. 编写业务逻辑接口,并实现它(UserManager, GhIKvX_N
9T*v9d
UserManagerImpl) FSA1gAW6g
java代码: '7iSp=
* /:x sI
lp(8E6
/*Created on 2005-7-15*/ U15H@h
package com.adt.service; ~V\D|W9
bp~g;h*E2
import net.sf.hibernate.HibernateException; FW21 U<
G1o3l~x
import org.flyware.util.page.Page; lLF-{
(aH'h1,G
import com.adt.bo.Result; ;N0~;I
yge,8i)c
/** {o.FlX
* @author Joa U
15H2-`
*/ z{o'
G3
publicinterface UserManager { lc~%=
d2H|LMhJ
public Result listUser(Page page)throws 2fWTY0
`wDl<[V
HibernateException; ,uSQNre\j
-@0GcUE:r
} *U
P@9D
EV*IoE$W]=
d%V*|0c)
tF{D= ;G
[E/\#4b
java代码: V;,{}
[<
&oF
a
0GpfW$t
/*Created on 2005-7-15*/ AMyIAZnYq)
package com.adt.service.impl; B>0].CK`
V{:A3C41
import java.util.List; USM4r!x
d~1gMz+)
import net.sf.hibernate.HibernateException; mqSQL}vR
4\4FolsK
import org.flyware.util.page.Page; lXjXqk\
import org.flyware.util.page.PageUtil; ]Ccg`AR{
4UW_Do
import com.adt.bo.Result; Vnr[}<L
import com.adt.dao.UserDAO; XYZ4TeW\1
import com.adt.exception.ObjectNotFoundException; +O*/"]h
import com.adt.service.UserManager;
+7=K/[9p
/Sc l#4bW
/** 'lEA)&d
* @author Joa fvdU`*|n)
*/ ^$'z!+QRM
publicclass UserManagerImpl implements UserManager { ]]oI#*c
Vv.|br`;}
private UserDAO userDAO; 6{^E{go
/XzH?n/{R
/** ,Q
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* @param userDAO The userDAO to set. u (em&M
*/ B#.L
publicvoid setUserDAO(UserDAO userDAO){ b"#WxgaF
this.userDAO = userDAO; Y}#J4i0b*
} d;>#Sxf
,^eYlmT>6
/* (non-Javadoc) G"Sd@%W(
* @see com.adt.service.UserManager#listUser VrxQc qPr`
2-C!jAfd
(org.flyware.util.page.Page) wv\w;'
*/ C'o64+W^
public Result listUser(Page page)throws !3 f?:M
Vp3ZwS
HibernateException, ObjectNotFoundException { h3z{(-~y
int totalRecords = userDAO.getUserCount(); 'i4_`^:+
if(totalRecords == 0) ,Qe?8En[
throw new ObjectNotFoundException tm#nU w
/Q2mMSK1h
("userNotExist"); Q=/</|
page = PageUtil.createPage(page, totalRecords); :$m}UA-9
List users = userDAO.getUserByPage(page); (}EB2V9Hh
returnnew Result(page, users); #py[
} |ayVjqJ*
}l],.J\BGX
} @!yMIM%P
vA]W|sLF9
q gLaa
%sX$nmi3
=p=rg$?
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 d\
1Og\U|A
qT`k*i?
询,接下来编写UserDAO的代码: :F{:Z*Fi0
3. UserDAO 和 UserDAOImpl: ;I}kQ!q
java代码: q(.:9A*0
b;cdIl!3
!,Va(E|=
/*Created on 2005-7-15*/ X@LRsg
package com.adt.dao; -/ g B|J
CJJzCVj
import java.util.List; &'}RrW-s
17G'jiYH
import org.flyware.util.page.Page; TTt#a6eJ
*22nVKi{
import net.sf.hibernate.HibernateException; hR
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C86J
IC"
/** a+!tT!g&I
* @author Joa 7lBAxqr2
*/ .QN>z-YA6:
publicinterface UserDAO extends BaseDAO { pnbIiyV
wT:b\km:!
publicList getUserByName(String name)throws t-0a7
1#e
-<
&D
HibernateException; cxr=k%~}J
INi]R^-
publicint getUserCount()throws HibernateException; I.94v
#r
b7wvaRe.
publicList getUserByPage(Page page)throws V&\[)D'c
+(1zH-^.
HibernateException; )XzI
#iQ
<\}KT*Xp
} HP3lz,d
w6W}"Uw
P)MDPI+~
(KF=On;=Y
twlk-2yT!
java代码: ; o0&`b?
$}jssnoU
YtfVD7m
/*Created on 2005-7-15*/ j&Wl0
package com.adt.dao.impl; >w^YO25q
k+8q{5>A<
import java.util.List; @ vrV*!
s!}ne"&0
import org.flyware.util.page.Page; KNLfp1!
7TDy.]
import net.sf.hibernate.HibernateException; 86mp=6@
import net.sf.hibernate.Query; Yo("U8:XX
=MLcm^b
import com.adt.dao.UserDAO; OC<5E121>Y
.P MZX%*v
/** -QmO1U
* @author Joa Q&eQQ6b^Ih
*/ M #=]
k
public class UserDAOImpl extends BaseDAOHibernateImpl cQ"~\
}C>{uXv
implements UserDAO { @Q/-s9b
82QGS$0V
/* (non-Javadoc) fIwV\,s
* @see com.adt.dao.UserDAO#getUserByName jr!?v<NoX
Lg*B>=
(java.lang.String) -cSP_1
*/ (;57 Vw
publicList getUserByName(String name)throws 66I"=:
?}a;}Q6
HibernateException { 45MLt5^|
String querySentence = "FROM user in class D? 8rO"
:C65-[PSdO
com.adt.po.User WHERE user.name=:name"; K/3)g9Z&io
Query query = getSession().createQuery 3T}izG]
],JEBt
(querySentence); XoCC/
query.setParameter("name", name); /i-J&*6_
return query.list(); JZD[N Z<
} =<X?sj5
.NvQm]N0.
/* (non-Javadoc) g47-db"5
* @see com.adt.dao.UserDAO#getUserCount() 'toa@5
*/ J~1r{5V4{
publicint getUserCount()throws HibernateException { =UJ:t Sr
int count = 0; n>^Y$yy}!
String querySentence = "SELECT count(*) FROM PV4(hj
3+G@g#MY
user in class com.adt.po.User"; 8$ma;U d
Query query = getSession().createQuery h0g:@ae%&
lobGj8uxq
(querySentence); d\61;C
count = ((Integer)query.iterate().next },>pDeX^P
Qkd<sxL
()).intValue(); }`v~I4i
return count; fbL\?S,w
} `^FGwx@
bV$)!]V
/* (non-Javadoc) YH%'t=
<m
* @see com.adt.dao.UserDAO#getUserByPage D[mSmpjE6&
O Vko+X`
(org.flyware.util.page.Page) 8rMX9qTO@
*/ Ar:*oiU
publicList getUserByPage(Page page)throws !2'jrJGc
-sjd&)~S[
HibernateException { (
|PAx(
String querySentence = "FROM user in class \CXQo4P
:I:!BXQT$
com.adt.po.User"; 4x;/HEb7?
Query query = getSession().createQuery ?kZTI (
{FIXc^m'
(querySentence); %QKRFPYhS
query.setFirstResult(page.getBeginIndex()) 00SbH$SU
.setMaxResults(page.getEveryPage()); 1}:bqI.<W
return query.list(); _:-ha?W$;y
} LX@/RAd vz
'`XX
"_k3
} )d$glI+
HN.3
u\LFlX0sO
q|v(Edt|_[
]"1`+q6i
至此,一个完整的分页程序完成。前台的只需要调用 0LfU=X0#7
&znQ;NH#
userManager.listUser(page)即可得到一个Page对象和结果集对象 KA){''>8
& M~`:R
的综合体,而传入的参数page对象则可以由前台传入,如果用 f~dd3m('
@Q^P{
webwork,甚至可以直接在配置文件中指定。 >9q&PEc
|iR T!
]
下面给出一个webwork调用示例: ;3kj2}
java代码: |kvC
H<F'
1e>s{
=7C%P%yt
/*Created on 2005-6-17*/ 8}FzZ?DRy
package com.adt.action.user; :L1dyVA{
HVP"A3}KC
import java.util.List; BvR-K\rx
91q8k=p
import org.apache.commons.logging.Log; i2sN3it
import org.apache.commons.logging.LogFactory; -Y*bSP)\
import org.flyware.util.page.Page; zD(`B+
H~+ l7OhV
import com.adt.bo.Result; awOd_![c'
import com.adt.service.UserService; cu% C"
import com.opensymphony.xwork.Action; H]$)Eg%6
lNL6M%e$Q
/** #%D_Y33;
* @author Joa t: IN,Kl4
*/ FRS>KO=3
publicclass ListUser implementsAction{ 05spovO/'
;[W"mlM
privatestaticfinal Log logger = LogFactory.getLog <IC~GqXv
EC\yzH*X
(ListUser.class); wQiX<)O
T[sDVkCbxf
private UserService userService; :k3Nt5t!
;}1xn3THCn
private Page page; baP^<w^
]6{*^4kX
privateList users; W3;#fa:[L
@EDs~ lPv
/* B"v.*
%"&/
* (non-Javadoc) KGWyJ
* 9(L)&S{4K
* @see com.opensymphony.xwork.Action#execute() s.x&LG
*/ L
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publicString execute()throwsException{
k0
Result result = userService.listUser(page); X*,%&6O*
page = result.getPage(); sL@U
users = result.getContent(); sPps q
return SUCCESS; Wa1,
p
} TzntO9P+
0%Z]h?EYy|
/** y /BJIQ
* @return Returns the page. ]\xy\\b/`
*/ ]_8qn'7
public Page getPage(){ i@B[ eta
return page; ~>:Z6Le@
} KrXdnY8
Ai/b\:V9S
/** }4{fQ`HT
* @return Returns the users. TD9;kN1`
*/ Xu>r~^w=S
publicList getUsers(){ r)1'ePI"
return users;
WJ
d%2pO]
} s-RQMK}H
~j#]tElb
/** OKP9CLg9
* @param page q-rB2
* The page to set. %rF?dvb;?
*/ \oEo~
publicvoid setPage(Page page){ "F}'~HWZp
this.page = page; -YjA+XP
} \/SQ,*O
H{AMZyV0/d
/** E!Zx#XP1
* @param users 0z[dlHi
* The users to set. k $fGom
*/ ?0
m\(#
publicvoid setUsers(List users){ x+h~gckLb
this.users = users; 1$2D O
} X5]TY]
\y88d4zX
/** Fk6x<^Q<w
* @param userService 8UMFq
* The userService to set. *5wu
*/ uu/+.9
publicvoid setUserService(UserService userService){ d @*GUmJ
this.userService = userService; [F*4EGB
} O4g+D#Lu
} s
(0*
78Aa|AJU
UDc$"a}ds{
{\z({Wlb]
&%2*Wu;
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 'r@:Cz3e*I
qU,c~C=Qf
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 8:o<ry
b:(-
么只需要: X<MO7I
java代码: 7nVRn9Hn
oM2UzB{(
{ K_kPgKS
<?xml version="1.0"?> x%<
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork =B ];?%
K9kUS
1.0//EN" "http://www.opensymphony.com/xwork/xwork- NB7Y{)
w
.,i(2^
1.0.dtd"> S#b-awk
QnI.zq
V
<xwork> >?]_<:
y?)}8T^
<package name="user" extends="webwork- J j=;
5PIZh<
interceptors"> ]u-02g
z**hD2R!
<!-- The default interceptor stack name oR~e#<$;
$x#FgD(iI
--> Xwa_3Xm*Le
<default-interceptor-ref x-'~Bu
,=~z6[
name="myDefaultWebStack"/> ai'4_
]O
TH"*j
<action name="listUser" IhiGP
{
BYM3jXWi0v
class="com.adt.action.user.ListUser"> R|P_GN6>
<param 4<X!<]3]
|3{&@7
name="page.everyPage">10</param> \@~UDP]7
<result 5 #]4YI;
K?4FT$9G
name="success">/user/user_list.jsp</result> QJW`}`R
</action> M|[ZpM+
fIocq
</package> G2#d$
Y=*P
8pg
</xwork> QR>
Y%4 ;h
>qo~d?+
7yt=]1
m7%C#+67
` r']^
,
Ao7 `G':
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 aVe/
gE
b}G24{
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 3I|3wQ (
}sxn72,
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 )ZejQ}$
;U`X 6d
>~\w+^2f8
+jqj6O@Tjr
jAND7&W
我写的一个用于分页的类,用了泛型了,hoho t=R6mjb
]bgY6@M
java代码: #*c F8NV-
'ZQWYr9R
33~qgK1>
package com.intokr.util; "Jy~PcJZ1
n(lk
dw
import java.util.List; Sg]
J7;]
S='syq>Aok
/** me\cLFw
* 用于分页的类<br> "%@uO)A /
* 可以用于传递查询的结果也可以用于传送查询的参数<br> pl V7+?G
* \;]kYO}
* @version 0.01 ArI]`h'W
* @author cheng }Uf<ZXW
*/ WA)Ij(M8 p
public class Paginator<E> { z{BA4sn
privateint count = 0; // 总记录数 m_!U}!
privateint p = 1; // 页编号 -qe bQv
privateint num = 20; // 每页的记录数 l
SkEuN
privateList<E> results = null; // 结果 x7RdZC
hxC!+ArVe
/** 137Xl>nO
* 结果总数 b>~RSO*
*/ XNH4==4
publicint getCount(){ VG*'"y*%w
return count; sFb4`
} f]d!hz!
Jbp5'e
_
publicvoid setCount(int count){ (Btv ClZ
this.count = count; y~F<9;$=
} ^GYq#q9Q
j5%qv(w
/** @ERu>nSP
* 本结果所在的页码,从1开始 WA
LGIW
* =V|Nn0E
* @return Returns the pageNo. :w?7j_p#
*/ g-yi xU
publicint getP(){ }.:d#]g8
return p; qi+&|80T.
} Cj&$%sO1
vv
7+>%
/** o6?l/nJ
* if(p<=0) p=1 2[dIOb4b
* +=8X8<Pu
* @param p FBsn;,3<W
*/ /qxJgoa
publicvoid setP(int p){ k|O,1
if(p <= 0) H2Eb\v`#
p = 1; G^Xd- 7 GQ
this.p = p; P Tnac
} 98*x 'Wp
acOJ]]
/** Dw |3Z
* 每页记录数量 7aQcP
*/ K!b8= K`
publicint getNum(){ pIVq("&
return num; 8mgQu]>
} n=`w9qajd
^t78jfl
/** n6d^>s9J
* if(num<1) num=1 p,n\__
*/ |5xz l
publicvoid setNum(int num){ `Lz1{#F2G
if(num < 1) lIuXo3
num = 1; "g
`nsk
this.num = num; (G8
} _=6 OP8
3 C"_$?y"
/** u3Do~RyL[
* 获得总页数 7C5pAb:
*/ ?Bu}.0ku-$
publicint getPageNum(){ tF`MT%{Va
return(count - 1) / num + 1; )!C7bTv 4
} <*YO~S(R
;,0lUcV
/** \n@V-b
* 获得本页的开始编号,为 (p-1)*num+1 9Q@*0-
*/ S?,_<GD)w
publicint getStart(){ M7VID6J.
return(p - 1) * num + 1; +5*vABvCu
} y`b\;kd
8D2yR#3
/** wZv-b*4
* @return Returns the results. bag&BHw
*/ pGGV\zD^
publicList<E> getResults(){ M5Wl3tZL
return results; =hcPTU-QU
} y[:q"BB3
ny`(f,)u*
public void setResults(List<E> results){ 99KVtgPm
this.results = results; [EGx
} !BRcq~-.
IIaxgfhZ
public String toString(){ XOxB
(0@
StringBuilder buff = new StringBuilder zKJ.Tj W
_[1^s$
();
1#D<ZN
buff.append("{"); d +xA:
buff.append("count:").append(count); k6J\Kkk(
buff.append(",p:").append(p); bp Ml =_
buff.append(",nump:").append(num); n{{P3f
buff.append(",results:").append M;qb7Mu
x(vai1CrdH
(results); tE:X,Lt[
buff.append("}"); +\U]p_Fo3
return buff.toString(); h^d\xn9GT#
} VV\Xb31J
!2tw, QM
} ru(J5+H
SKJW%(|3
Q)+Y}