Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 q.MVF]
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ?4ILl>*
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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 h_~|O[5|)
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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 _?s %MNaX
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分页支持类: ^QAiySR`0
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java代码: .H^P2tp
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package com.javaeye.common.util; 5ttMua <G?
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import java.util.List; C,r`I/;
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publicclass PaginationSupport { NGD*ce"w
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publicfinalstaticint PAGESIZE = 30; 7B(bH8
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privateint pageSize = PAGESIZE; u<]mv
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privateList items;
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privateint totalCount; voV:H[RD9
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privateint[] indexes = newint[0]; jJVT_8J
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privateint startIndex = 0; 7':f_]
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public PaginationSupport(List items, int |qlS6Aln
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totalCount){ e8WEz
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setPageSize(PAGESIZE); kT^*>=1
setTotalCount(totalCount); ku9@&W+
setItems(items); nlzW.OLM
setStartIndex(0); ALd]1a&
} \2Og>{"U
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public PaginationSupport(List items, int
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totalCount, int startIndex){ JoCA{Fa}
setPageSize(PAGESIZE); ,;.B4
setTotalCount(totalCount); EqnpMHF
setItems(items); 't(}Rq@
setStartIndex(startIndex); 'Y!pY]Z
} {7?9jEj
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public PaginationSupport(List items, int l(%k6
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totalCount, int pageSize, int startIndex){ CE#\Roi x)
setPageSize(pageSize); a@#Q:O)4
setTotalCount(totalCount); ]U,CKJF%/
setItems(items); x_==Ss
setStartIndex(startIndex); )nwZ/&@
} H&X:!xa5
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publicList getItems(){ F>dwL bnb
return items; :N@U[Wx0A
} %bP~wl~
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publicvoid setItems(List items){ Yb[n{.%/g
this.items = items; zF5q=9 4$
} \=!H 2M
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publicint getPageSize(){ p jKt:R}
return pageSize; X>8-`p
} M$Fth*q{GD
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publicvoid setPageSize(int pageSize){ N = LM?(H
this.pageSize = pageSize; RF_[?O)Q
} W+gpr|R2
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publicint getTotalCount(){ A&?}w_|9
return totalCount; BeK2;[5C
} Ge~q3"
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publicvoid setTotalCount(int totalCount){ =m}TU)4.
if(totalCount > 0){ ^m*3&x8
this.totalCount = totalCount; E4+b-?PB~
int count = totalCount / 6Rcua<;2P
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pageSize; 4`nqAX~'f
if(totalCount % pageSize > 0) BhKO_wQ?:J
count++; L=,OZ9aA
indexes = newint[count]; }Y Q:6I
for(int i = 0; i < count; i++){ qZaO&"q
indexes = pageSize * McjS)4j&.
{j?7d; 'j
i; RqXi1<6j#
} ]pnYvXf>!
}else{ =3*Jj`AV
this.totalCount = 0; |rMq;Rgu?
} n)#Lh
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} k oM]S+1
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publicint[] getIndexes(){ p*|ah%F6N
return indexes; vMhYpt?7\
} :BZMnCfA
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publicvoid setIndexes(int[] indexes){ Ikj=`,a2B
this.indexes = indexes; iZQ\
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} b,dr+RB
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publicint getStartIndex(){ i\Yl
return startIndex; Ep mJWbU
} +Hj/0pp
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publicvoid setStartIndex(int startIndex){ xO7Yt
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if(totalCount <= 0) {"m0)G,G
this.startIndex = 0; p1D()-
elseif(startIndex >= totalCount) 9?
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this.startIndex = indexes HT"gT2U+
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[indexes.length - 1]; SK+@HnKd
elseif(startIndex < 0) \~>e_;
this.startIndex = 0; ExCM<$,
else{ s~J=<)T*6
this.startIndex = indexes -es"0wS<u
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[startIndex / pageSize]; WmNYO,>
} t?{B_Bf
} -`7$Qu2
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publicint getNextIndex(){ VD$Eb
int nextIndex = getStartIndex() + mV?&%>*(f
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pageSize; :y#T9R9
if(nextIndex >= totalCount) p0M=t-
return getStartIndex(); o.Oq__ >$H
else Nb;H`<JP
return nextIndex; )TU<:V
} h*Je35
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publicint getPreviousIndex(){ Uoji@
int previousIndex = getStartIndex() - s<vs:jna
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pageSize; zAs&%OjG
if(previousIndex < 0) ;W{b $k@g
return0; MzzKJ;wbC6
else 9#k0_vDoW
return previousIndex; p@ygne4
} r`6:Q&&
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}
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抽象业务类 *HE^1IEl
java代码: L8&D(wh/f
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/** 3;_
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* Created on 2005-7-12 -(#-I$z
*/ mS%4gx~~_n
package com.javaeye.common.business; ;`(R7X
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import java.io.Serializable; 8IGt4UF&?
import java.util.List; _1|$P|$P.
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import org.hibernate.Criteria; 7I}P*%(f
import org.hibernate.HibernateException; -M4p\6)Ge
import org.hibernate.Session; ``|AgIg
import org.hibernate.criterion.DetachedCriteria; 30Drrno7Io
import org.hibernate.criterion.Projections; dE5D3ze
import >xg5z
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org.springframework.orm.hibernate3.HibernateCallback; 8TWTbQ
import CQ^3v09N;~
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org.springframework.orm.hibernate3.support.HibernateDaoS E0 l_--
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upport; -5bA
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import com.javaeye.common.util.PaginationSupport; @r;wobt
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public abstract class AbstractManager extends UE :HMn6
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HibernateDaoSupport { &@v<nO-
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privateboolean cacheQueries = false; \we\0@v
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privateString queryCacheRegion; HpW 42
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publicvoid setCacheQueries(boolean #sB,1"
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cacheQueries){ d]wD[]
this.cacheQueries = cacheQueries; ?+2b(2&MXE
} PmX2[7
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publicvoid setQueryCacheRegion(String h<6UC%'ac
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queryCacheRegion){ h7yqk4'Lq
this.queryCacheRegion = Ev9> @~^
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queryCacheRegion; izZ=d5+K
} D'_Bz8H!p
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publicvoid save(finalObject entity){ C~4PE>YtTv
getHibernateTemplate().save(entity); %.HJK
} zsXpA0~3s
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publicvoid persist(finalObject entity){ #8h;Bj
getHibernateTemplate().save(entity); p(JlvJjo
} c EnkU]
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publicvoid update(finalObject entity){ BR5BJX
getHibernateTemplate().update(entity); LT@OWH
} x/fX`y|(}*
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publicvoid delete(finalObject entity){ K^[#]+nQ
getHibernateTemplate().delete(entity); {+.r5py
} Ao9R:|9
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publicObject load(finalClass entity, %O[N}_XHEh
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finalSerializable id){ ?>
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return getHibernateTemplate().load GqKsK
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(entity, id); B 0ee?VC
} 'gMfN
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publicObject get(finalClass entity, ,)FdRRj
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finalSerializable id){ B4Y(?JTx
return getHibernateTemplate().get #*%q'gyHT
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(entity, id); Nw_@A8-r
} #qBr/+b
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publicList findAll(finalClass entity){ p#P~Q/;
return getHibernateTemplate().find("from /=?x{(B>
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" + entity.getName()); YDJ4c;37
} nIk$7rGLB
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publicList findByNamedQuery(finalString U(>4s]O6
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namedQuery){ H}}$V7]^),
return getHibernateTemplate O[^%{'
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().findByNamedQuery(namedQuery); G6 0S|d
} YwEpy(}hJm
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publicList findByNamedQuery(finalString query, yay<GP?
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finalObject parameter){ o{qr!*_3
return getHibernateTemplate X2sH E
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().findByNamedQuery(query, parameter); ?%tMohL
} 2B0W~x2=
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publicList findByNamedQuery(finalString query,
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finalObject[] parameters){ {Azn&|%.t
return getHibernateTemplate LpbsYl
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().findByNamedQuery(query, parameters); DTRJ/@t
} 1Na@|yY
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publicList find(finalString query){ 6fo3:P*O
return getHibernateTemplate().find "I6P=]|b
/*FH:T<V
(query); I=)hWC/
} 2&mGT&HAVA
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publicList find(finalString query, finalObject x&sI=5l
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parameter){ IY'=DePd
return getHibernateTemplate().find ;ea]$9
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(query, parameter); :$;Fhf<5
} 3981ie
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public PaginationSupport findPageByCriteria `_I@i]i^
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(final DetachedCriteria detachedCriteria){ OVzt\V*+%W
return findPageByCriteria jdZ~z#`(!:
!)"%),>}o
(detachedCriteria, PaginationSupport.PAGESIZE, 0); lf{e[!ML'
} ~)LH='|h\}
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public PaginationSupport findPageByCriteria {R<Ea
@LV+
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(final DetachedCriteria detachedCriteria, finalint i$G;f^Z!Y
(
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startIndex){ h+p*=|j`
return findPageByCriteria u@'0Vk0zGH
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(detachedCriteria, PaginationSupport.PAGESIZE, K5ZC:Ks
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startIndex); ;7]u!Q
} 5,qj7HZF
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public PaginationSupport findPageByCriteria '|]e<Mt-
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(final DetachedCriteria detachedCriteria, finalint 0]KraLu"N
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pageSize, ]xC#rwHUC
finalint startIndex){ Ac2(O6
return(PaginationSupport) q5h*`7f
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getHibernateTemplate().execute(new HibernateCallback(){ Q$& sTM
publicObject doInHibernate AqKz$
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(Session session)throws HibernateException { 'w>_+jLT
Criteria criteria = #/"8F O%~p
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detachedCriteria.getExecutableCriteria(session); W>r#RXmh
int totalCount = ?]fF3 SJk
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((Integer) criteria.setProjection(Projections.rowCount qPB8O1fyU
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()).uniqueResult()).intValue(); IEKU-k7}Z
criteria.setProjection #_lt~^6
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(null); U~h'*nV&
List items = xq-17HKs
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criteria.setFirstResult(startIndex).setMaxResults :tIC~GG]_)
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f
(pageSize).list(); /27JevE
PaginationSupport ps = U4m9e|/H;z
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new PaginationSupport(items, totalCount, pageSize, \!(
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startIndex); ZX ?yL>4
return ps; D3|oOOoG
} TG}*5Z`
}, true); 0TfS=scT
} tz#gClo
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public List findAllByCriteria(final /9o!*K
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DetachedCriteria detachedCriteria){ !d<"nx[2`
return(List) getHibernateTemplate k(zsm"<q
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().execute(new HibernateCallback(){ O: @}lK+H
publicObject doInHibernate m(], r})
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(Session session)throws HibernateException { 0|R# Tb;Y
Criteria criteria = iXyO(w4D
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detachedCriteria.getExecutableCriteria(session); *f,DhT/P
return criteria.list(); J]m{b09F
} z0|&W&&D
}, true); xs\!$*R
} K;LZ-
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public int getCountByCriteria(final .(pN5JI*
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DetachedCriteria detachedCriteria){ \Mg`(,kwe
Integer count = (Integer) [tMZ G%h
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getHibernateTemplate().execute(new HibernateCallback(){ R!l:O=[<
publicObject doInHibernate u:aW 8
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(Session session)throws HibernateException { SQeRSz8bK4
Criteria criteria = YF+n
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detachedCriteria.getExecutableCriteria(session); Wf{O[yL*
return sAg Kg=)
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criteria.setProjection(Projections.rowCount "V&+7"Q
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()).uniqueResult(); )lJao
} {.yStB.T
}, true); ]xguBh ]
return count.intValue(); E*# ]**
} ?$e9<lsQq)
} VUI|.76g
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用户在web层构造查询条件detachedCriteria,和可选的 #2`D`>7456
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 z,{<Nm7&F
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PaginationSupport的实例ps。 wH~kTU2br
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ps.getItems()得到已分页好的结果集 0flg=U9
ps.getIndexes()得到分页索引的数组 Ela-,(Glk
ps.getTotalCount()得到总结果数 M-i_#EWP
ps.getStartIndex()当前分页索引 &Q}*+Y]G
ps.getNextIndex()下一页索引 Xn~I=Ml d
ps.getPreviousIndex()上一页索引 &-5_f*{
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 v\`9;QV5
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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 8EVgoJ.
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一下代码重构了。 a,78l@d(
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我把原本我的做法也提供出来供大家讨论吧: s}pIk.4ot!
D1nq2GwS
首先,为了实现分页查询,我封装了一个Page类: )"+(butI&
java代码: !?^b[
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/*Created on 2005-4-14*/ H5D*|42
package org.flyware.util.page; -48vJR*tC
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/** g@\fZTO
* @author Joa
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* Tr^nkD{
*/ k1VT /u
publicclass Page { V^Hu3aUx8
=}PdH`S
/** imply if the page has previous page */ .'a&33J
privateboolean hasPrePage; )]#aa uC+
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/** imply if the page has next page */ wu"&|dt
privateboolean hasNextPage; b=3H
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/** the number of every page */ nNXgW
privateint everyPage; `Y?87f:SP
<, 3ROo76
/** the total page number */ c^`]`xiX
privateint totalPage; %7O?JI[
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/** the number of current page */ ki>~H!zB
privateint currentPage; ""Q1|
v`1,4,;,qs
/** the begin index of the records by the current |a{Q0:
)/t?!T.[
query */ C;(t/zh
privateint beginIndex; 42L
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/** The default constructor */ M@W[Bz
public Page(){ sl*5Y#,|1
O0>A+o[1F
} xAggn
@]bPVG?d
/** construct the page by everyPage 2S' {!A
* @param everyPage _j_x1.l
* */ 'H7x L
public Page(int everyPage){ `-3o+ID\
this.everyPage = everyPage; -X+H2G
} ?aW^+3i
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/** The whole constructor */ X>?b#Eva
public Page(boolean hasPrePage, boolean hasNextPage, @*
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int everyPage, int totalPage, X\}Y
int currentPage, int beginIndex){ rWh6RYd<T
this.hasPrePage = hasPrePage; R/`q/0T.
this.hasNextPage = hasNextPage; lgpW@g
this.everyPage = everyPage; OIl#DV.
this.totalPage = totalPage; q$G,KRy/
this.currentPage = currentPage; ~8aJ S,u
this.beginIndex = beginIndex; c]B$i*t
} LK"
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/** e|4&b@
* @return *._|- L
* Returns the beginIndex. Dup;e&9g
*/ .d/:30Y
publicint getBeginIndex(){ 4d:{HLX,
return beginIndex; s_.]4bl.8
} a?YCn!
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/** |y20Hi':
* @param beginIndex m5G \}8|
* The beginIndex to set. 2&Nb
*/ -CH`>
publicvoid setBeginIndex(int beginIndex){ U}SXJH&&E
this.beginIndex = beginIndex; a(]`F(L
} L !4t[hhe=
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/** ob_I]~^I?|
* @return ^TB>.c@ `*
* Returns the currentPage. *)]"27^
*/ fFjH "2WD
publicint getCurrentPage(){ q %A?V_
return currentPage; )5fQ$<(Z
} HyiFy7j
.}')f;jH5<
/** !se0F.K
* @param currentPage 4x%(9_8{-
* The currentPage to set. [#YE^[*qK
*/ H&b3{yOa
publicvoid setCurrentPage(int currentPage){ )rLMIk
this.currentPage = currentPage; .yENM[-bQ
} G#Ou[*O'
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/** LflFe@2
* @return yk2 !8
* Returns the everyPage. 97!>%d[0
*/ z'p:gv]
publicint getEveryPage(){ Da$r `
return everyPage; 27ckdyQx
} X}P$emr7
>ds%].$-\
/** 0tk#Gs[
* @param everyPage Cc?TSZ8[
* The everyPage to set. clI*7j.4E#
*/ gfU-"VpHE
publicvoid setEveryPage(int everyPage){ &/.hx(#d
this.everyPage = everyPage; V E2tq k%
} +MK6zf
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/** +*oS((0s
* @return >Q,zNs
* Returns the hasNextPage. e7u^mJ
*/ ZV}X'qGaq
publicboolean getHasNextPage(){ hgRVwX
return hasNextPage; {J/I-=CmML
} zq5'i!s !0
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/** 1r r@
* @param hasNextPage mmw^{MK!
* The hasNextPage to set. Q
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*/ =G~~?>=@2
publicvoid setHasNextPage(boolean hasNextPage){ (wRBd
this.hasNextPage = hasNextPage; 'cDx{?
} 0%s|Zbo!>
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/** URcR
* @return %[<Y9g,:Q
* Returns the hasPrePage. o-7>eE}+
*/ vtJV"h?e"3
publicboolean getHasPrePage(){ N12:{U
return hasPrePage; bt+,0\Vg5
} _nT{g
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/** Y^"4?96
* @param hasPrePage m8+(%>+7
* The hasPrePage to set. l^NC]t
*/ D}Ilyk_uUw
publicvoid setHasPrePage(boolean hasPrePage){ F="z]C;u
this.hasPrePage = hasPrePage; V%HS\<$h
} lhC6S'vq
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/** f<y&\'3
* @return Returns the totalPage. 'UM!*fk7C
* SN+S6
*/ !rxp?V n -
publicint getTotalPage(){ /7$mxtB5%L
return totalPage; 47 u@4"M
} E(<LvMiCa
+V v+K(lh$
/** ZeasYSo4P
* @param totalPage $7I]`Jt
* The totalPage to set. jj\ [7 O*
*/ kR.wOJ7'
publicvoid setTotalPage(int totalPage){ *.y' (tj[
this.totalPage = totalPage; wCZO9sU:6=
} QL"gWr`R
D_|B2gdZY
} hQJWKAf,/
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P#GD?FUc
AZFWuPJo
|U[y_Y\a
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 #_Ea[q7v
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个PageUtil,负责对Page对象进行构造: 0rMqWP
java代码: urY`^lX~
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/*Created on 2005-4-14*/ +?-qfp,:0
package org.flyware.util.page; w`yx=i#
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import org.apache.commons.logging.Log; coQ[@vu
import org.apache.commons.logging.LogFactory; ){Z
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/** /rF8@l
* @author Joa &jts:^N>
* #dJ 2Q_2
*/ PNF4>)
publicclass PageUtil {
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Pw}_[[>$
privatestaticfinal Log logger = LogFactory.getLog >M^&F6
y{rn-?`{
(PageUtil.class); C@dGWAG
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/** 5ouQQ)vA
* Use the origin page to create a new page qR,.W/eS8
* @param page *M!kA65'
* @param totalRecords `ENP=kL(+
* @return P!\hnm)%4
*/ lC9S\s
publicstatic Page createPage(Page page, int I{n;4?
!y vJpdsof
totalRecords){ p?myuNd[
return createPage(page.getEveryPage(), q@ Kk\m
@[r ={s\
page.getCurrentPage(), totalRecords); n! .2aq
} t!l%/$-
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/** <%!J?
* the basic page utils not including exception 4]6 Qr
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handler HCc`
* @param everyPage g37q/nEv
* @param currentPage G*\sdBW!k
* @param totalRecords ^pcRW44K
* @return page ?iln<%G
*/ @%B4;c
publicstatic Page createPage(int everyPage, int )1_(>|@oi
:GL7J6
currentPage, int totalRecords){ RWE~&w G}
everyPage = getEveryPage(everyPage); X(GV6mJ4
currentPage = getCurrentPage(currentPage); q:yO92Ow
int beginIndex = getBeginIndex(everyPage, jfSg){
4;\Y?M}g?
currentPage); `C<F+/q
int totalPage = getTotalPage(everyPage, $9i9s4u^
PRpE$`WK
totalRecords); G]lvHD
boolean hasNextPage = hasNextPage(currentPage, :ej_D}
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totalPage); 3i(J on/p
boolean hasPrePage = hasPrePage(currentPage); uu3M{*}
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returnnew Page(hasPrePage, hasNextPage, >-<F)
everyPage, totalPage, Yq0# #__
currentPage, X8b#[40:
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beginIndex); n#>5?W
} `cO|RhD@
no3Z\@%
privatestaticint getEveryPage(int everyPage){ cj^bh
return everyPage == 0 ? 10 : everyPage; &|z|SY]DL
} %]GV+!3S
)OUU]MUH
privatestaticint getCurrentPage(int currentPage){ c! ~T2t
return currentPage == 0 ? 1 : currentPage; e?vj+ZlS$f
} i puo}
WY.5K
=}
privatestaticint getBeginIndex(int everyPage, int U3VT*nj'
S>EDL
currentPage){ E!dp~RwZu
return(currentPage - 1) * everyPage; ;Xh5oB\)W
} [0(mFMC`
cyb(\ fsC
privatestaticint getTotalPage(int everyPage, int \>;%Ji
j]4,6`b\
totalRecords){ S~|tfJpL
int totalPage = 0; D2?S,9+E_
&NP6%}bR`
if(totalRecords % everyPage == 0) ~*kK4]lP
totalPage = totalRecords / everyPage; Bn_g-WrT
else }#|2z}!
totalPage = totalRecords / everyPage + 1 ; [k~C+FI
P,`=]Y*
return totalPage; .)0gz!Z
} e#m1X6$.e
(-'PD_|
privatestaticboolean hasPrePage(int currentPage){ /xf.\Z7<
return currentPage == 1 ? false : true; U
TS{H
} wKLN:aRF2
D{3fhPNU<b
privatestaticboolean hasNextPage(int currentPage, P|v ?
lR[z<2w\
int totalPage){ 6,zDBax
return currentPage == totalPage || totalPage == [[$Mh_MD
dL(4mR8
0 ? false : true; D0KELAcY
} i2U/RXu
E]?2!)mgce
d~,n_E$q;
} yW:AVqE)t
YOlH*cZtg
klo^K9!
YiO3<}Uf
U#$:\fT
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。 P8u"T!G
?qIGQ/af&
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 H<{*ub4'L*
@@; 1%z
做法如下: S~} +ypV
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象
Jb6&
qWkx:-g]
的信息,和一个结果集List: W -3w7^
java代码: o=@ UXi
Hj1k-Bs&'w
DSTx#*
/*Created on 2005-6-13*/ 5 5a@)>h
package com.adt.bo; -/1d&
l2r>|CGQ[
import java.util.List; vevx|<9,
sbpu
qOL
import org.flyware.util.page.Page; ,qYf#fU#7
={OCa1
/** KM E XT$p
* @author Joa &9k"9
*/ i /C'0
publicclass Result { l; */M.B
B piEAwh
private Page page; S[ i$e
\:C%>
.VG
private List content; xvHOY:
"_Zh5
g
/** mJ/^BT]
* The default constructor QK,=5~I J
*/ :0{AP_tvcC
public Result(){ -<_+-t
super(); Cnk#Ioz
} '\4c "Ho
n2H&t>N
/** ;k-g_{M
* The constructor using fields }D(DU5r
* _8Pmv$
* @param page yFIl^Ck%
* @param content PZ~`O
*/ EC0zH#N
public Result(Page page, List content){ n&3iz05}
this.page = page; e3G7K8
this.content = content; u87=q^$
} q=J9LQ
-i2D#i'
/** Z+OAs0}mV
* @return Returns the content. T<!\B]
*/ 3{6ps : w
publicList getContent(){ o$*bm6o
return content; f;&` 9s| 1
} Au~+Zz|mQ
A3m{jbh
/** q|?`Gsr
* @return Returns the page. 8|fLe\"
*/ D<lQoO+
public Page getPage(){ Cln^ 1N0
return page; NU BpIx&
} 5+o
2 T]
VZAuUw+M
/** W`
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* @param content &E} I
* The content to set. `8.1&fBr
*/ IY-(-
a8
public void setContent(List content){ XL{{7%j
this.content = content; HCI'q\\
} yIn/Y 0No
gNG0k$nP
/** vsOdp:Yp9!
* @param page eV@4VxaZ
* The page to set. `M towXj
*/ }(8D!XgWa
publicvoid setPage(Page page){ z0EjIYI[N
this.page = page; #p']-No
} L{4),65
} f$~ _FX
qiF@7i
V.O<|tl.
"it`X
B.
UwvGr h
2. 编写业务逻辑接口,并实现它(UserManager, 3'|Uqf8
]?v?Qfh2
UserManagerImpl) k^L#,:\&V
java代码: GLbc/qs
l"2^S6vU
EOMuqP)
/*Created on 2005-7-15*/ O7Y
P_<,#
package com.adt.service; PT
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!y[}|
import net.sf.hibernate.HibernateException; z(8)1#(n7
h0'8NvalQ
import org.flyware.util.page.Page; d m/-}
[ flu|v
import com.adt.bo.Result; ^TuP=q5?
G~b`O20N
/** H5F\-&cq
* @author Joa [a#?}((
*/ ?uNTUU,
publicinterface UserManager { 4i ~eTb
xg*\j)_}
public Result listUser(Page page)throws ~z-?rW
bn^mL~
HibernateException; -N /8Ho
}.fZy&_
} "t3uW6&
tal>b]B;
o(v"?Y 6
U]`'GM/x
`2
%eDFZ
java代码: b<29wL1
s0X/1Cq
HM(bR"E
/*Created on 2005-7-15*/ MbT
ONt?~v
package com.adt.service.impl; [="g|/M)
W07-JHV%
import java.util.List; AaCnTRG
:
9djMsd
import net.sf.hibernate.HibernateException; CWobvR)e
&V ^
import org.flyware.util.page.Page; Xy3g(x]
import org.flyware.util.page.PageUtil; Y%n{`9=
)sqp7["-
import com.adt.bo.Result; : pE-{3I
import com.adt.dao.UserDAO; +Tgy,oD0
import com.adt.exception.ObjectNotFoundException; F1{?]>G
import com.adt.service.UserManager; Mdy0!{d
S?,KgMVM
/** [FeJ8P>z
* @author Joa mlsvP%[f.
*/ vkNZ -`+I
publicclass UserManagerImpl implements UserManager { IxK 3,@d
ZYl-p]\*y
private UserDAO userDAO; 6I5[^fv45G
)Ta]6
/** YKs^%GO+
* @param userDAO The userDAO to set. \pBYWf
*/ @@&@}IQcR1
publicvoid setUserDAO(UserDAO userDAO){ j:de}!wc
this.userDAO = userDAO; &\WkJ}&PnA
} n{qa ]3
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/* (non-Javadoc) ^Yf)lV&[
* @see com.adt.service.UserManager#listUser dctA`W@:-
~,M;+T}[r
(org.flyware.util.page.Page) Kc-A-P &Ry
*/ o%N0K
public Result listUser(Page page)throws I49=ozPP
n41\y:CAo
HibernateException, ObjectNotFoundException { {$u@6&
B
int totalRecords = userDAO.getUserCount(); gs`27Gih
if(totalRecords == 0) FzsS~C$wH{
throw new ObjectNotFoundException K_<lO,[S
<Vr]2mw
("userNotExist"); lhIr]'?l
page = PageUtil.createPage(page, totalRecords); c!(~BH3p
List users = userDAO.getUserByPage(page); {8>_,z^P)
returnnew Result(page, users); iBPdCp%]`
} nfd?@34"A2
Rm[rQ}:
} i+T0}M<
)n3biQL_
4%c7#AX[T
B9;,A;E};
9cw4tqTm
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 =Y=^]ayO/
S*DBY~pZy
询,接下来编写UserDAO的代码: [<3Q$*Ew
3. UserDAO 和 UserDAOImpl: [u9S+:7"
java代码: B#Oc8`1Y
d@q t%r3;
ui#1 +p3G
/*Created on 2005-7-15*/ 5>z:[OdY*
package com.adt.dao; lG[
)8!:+
sP8-gkkor
import java.util.List; "#eNFCo7k
pFv[z':&Q
import org.flyware.util.page.Page; >/OXC+=^4
_
/28Cw
import net.sf.hibernate.HibernateException; i5~ /+~
&oK/]lub
/** R^Eu}?<f
* @author Joa +D{*L0$D"
*/ 83 ^,'Z
publicinterface UserDAO extends BaseDAO { "=Fn.r4I
U~zN*2-
publicList getUserByName(String name)throws [0,q7d?"
MkV*+LXC
HibernateException; GWkJ/EX
(j"~]T!)1
publicint getUserCount()throws HibernateException;
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E*!zJ,@8
publicList getUserByPage(Page page)throws Xm:gD6;9
krnk%ug
HibernateException; n-| i
nY5n%>8
} K&a]pL6D
wGQ hr="
5)zh@aJ@
%[bO\,
F*jjcUk
java代码: J/&*OC
Qmc;s{-r;
XGup,7e9
/*Created on 2005-7-15*/ [{!j9E?(
package com.adt.dao.impl; OaCj3d>
z?) RF[
import java.util.List; 2.L6]^N p(
8!fAv$g0
import org.flyware.util.page.Page; e!x-:F#4j
9oau_Q#
import net.sf.hibernate.HibernateException; !m O] zn
import net.sf.hibernate.Query; g}og@UY7#
VEYKrZA
import com.adt.dao.UserDAO; DBh/V#* D
&T/9yW[L
/** -0J<R;cVs
* @author Joa j]F3[gpc
*/ E?5B>Jer#
public class UserDAOImpl extends BaseDAOHibernateImpl ;NVTn<Uj
U!UX"r
implements UserDAO { qxCL
2d J)4
/* (non-Javadoc) `r0
qn'*
* @see com.adt.dao.UserDAO#getUserByName n7!Lwq2
lJQl$Wx^
(java.lang.String) 7)It1i-
*/ &\D<n;3
publicList getUserByName(String name)throws Sw9mrhzJfe
G;#t6bk
HibernateException { IhKas4
String querySentence = "FROM user in class +z?f,`.*
.$}zw|,q
com.adt.po.User WHERE user.name=:name"; FZ.Yn
Query query = getSession().createQuery !rmo*-=^=
5N</Z6f'o
(querySentence); n)7$xYuH
query.setParameter("name", name); ]be2jQx3
return query.list(); \c^jaK5
} O
NzdCgY
kk./-G
/* (non-Javadoc) 3:gO7Uv
* @see com.adt.dao.UserDAO#getUserCount() v@1Jhns
*/ Hw. @Le>
publicint getUserCount()throws HibernateException { `,]PM)iC
int count = 0; -#z'A
String querySentence = "SELECT count(*) FROM vh3iu+
<yaw9k+P
user in class com.adt.po.User"; #:5g`Ch4,
Query query = getSession().createQuery ~5qZs"ks
f6A['<%o
(querySentence); F"? *@L
count = ((Integer)query.iterate().next ?BZ`mrH^
X1QZEl
()).intValue(); k#G7`dJl
return count; (dnc7KrM
} K]Cs2IpI
iK0J{'
/* (non-Javadoc) 3T^dgWXEG
* @see com.adt.dao.UserDAO#getUserByPage >N"PLSY1
MBrVh6z>
(org.flyware.util.page.Page) pY5HW2TsY|
*/ BJ2W}R
publicList getUserByPage(Page page)throws `fh_8%m]*
gM[
J'DMW
HibernateException { g5N<B+?!i
String querySentence = "FROM user in class 7027@M?A?
`5jB|r/
com.adt.po.User"; 6? ly.h$
Query query = getSession().createQuery 0s[3:bZ\Ia
qCT\rZU
(querySentence); _( /lBf{|
query.setFirstResult(page.getBeginIndex()) gxtbu$
.setMaxResults(page.getEveryPage()); k"-#ox!
return query.list(); eC:Q)%$%l
} iz5wUyeg
W%QtJB1)
} ~TIZumGB
TmH13N]
hds4_
eTHh
6u3(G j@
至此,一个完整的分页程序完成。前台的只需要调用 >x0lSL0y
m)w-mc
userManager.listUser(page)即可得到一个Page对象和结果集对象 -\v8i.w0
>5W"a?(
的综合体,而传入的参数page对象则可以由前台传入,如果用 L 'Rapu
1caod0gor
webwork,甚至可以直接在配置文件中指定。 [m&ZAq
q9]L!V9Rv
下面给出一个webwork调用示例: LZ dNG\-
java代码: r}Av"
_
9]3S>Rn
I"?&X4%e
/*Created on 2005-6-17*/ e!'u{>u
package com.adt.action.user; (19<8a9G
u6d~d\
import java.util.List; 4=cq 76
YIqfGXu8
import org.apache.commons.logging.Log; .?]_yX
import org.apache.commons.logging.LogFactory; K0a
50@B]
import org.flyware.util.page.Page; }-iOYSn
kfECC&"
import com.adt.bo.Result; f_Bf}2Eedj
import com.adt.service.UserService; DMW:%h{
import com.opensymphony.xwork.Action; (fb\A6
Lwk-
/** W4Q]<<6&
* @author Joa ogbdt1
*/ be@uHikp;v
publicclass ListUser implementsAction{ 3o^M%
^Z+D7Q
privatestaticfinal Log logger = LogFactory.getLog >1zzDd_
p$ v +L
(ListUser.class); z*1K<w8
uS,$P34^oy
private UserService userService; f/m6q8!L{
bd}SB -D
private Page page; ?QVI'R:Z?
-2d&Aq4m)
privateList users; ;Nij*-U4~
T6#GlO)8)
/* 11+_OC2-
* (non-Javadoc) !7?wd^C'f
* L<`g}iw
* @see com.opensymphony.xwork.Action#execute() 9x,+G['Zt
*/ C
=U4|h ~W
publicString execute()throwsException{ KHiJOeLc
Result result = userService.listUser(page); OO>2oH
page = result.getPage(); pBLO
users = result.getContent(); ??Ac=K\
return SUCCESS; 7^5BnF@
} ;O>fy:$'
5,Zn$zosJC
/** WQ`T'k#ESW
* @return Returns the page. i(rY'o2 BN
*/ net9KX4\
public Page getPage(){ px@\b]/
return page; H:6$)#
} `h6W@ROb
INpub5
/** G> >_G<x
* @return Returns the users. A4h/oMis
*/ g.s oNqt=
publicList getUsers(){ rg.if"o
return users; H)tDfk sq\
} F{tSfKy2
L~~Yh{<
/** cw{[B%vw
* @param page Y?cw9uYB
* The page to set. |&vuK9q
*/ o5R40["
publicvoid setPage(Page page){ nrBitu,
this.page = page; <X*8Xzmv
} -}o;Y)
_#B/#^a
/** *E'K{?-K
* @param users O6]~5&8U.
* The users to set. W[s>TDc`v
*/ ba13^;fm#
publicvoid setUsers(List users){ H=C;g)R
this.users = users; P+h&tXZn8
} ZbUf|#GTB
p6'8l~W+
/** v'tk:Hm1
* @param userService *2F}e4v
* The userService to set. zdE^v{}|
*/ /+msrrpD
publicvoid setUserService(UserService userService){ X Rn=;gK%J
this.userService = userService; 6Y^o8R
} {J$aA6t:"T
} $!Tw`O
@@jdF-Utj;
J7xmf,76w
1S.~-K*X
':3KZ4/C
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, FQ%mNowuj
lDeWs%n
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 !=:c8V
~A/_\-
么只需要: LNkyV*TI
java代码: 3
6
;hg#
"f_Z.6WMY
a2TC,
<?xml version="1.0"?> g:U ul4
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork cht#~d
ZtVa*xl
1.0//EN" "http://www.opensymphony.com/xwork/xwork- O [/~V=
b3+PC$z2h
1.0.dtd"> S6]':
1oPT8)[U
<xwork> >q`X%&l_
L@XeAEIq
<package name="user" extends="webwork- \~PFD%]:3
?F/3]lsggT
interceptors"> *rLs!/[Z_
sXu]k#I^"
<!-- The default interceptor stack name lS^0*(Y
@zbXG_J
--> }8HLyK,4
<default-interceptor-ref i7FEjjGtG
JFZ p^{
name="myDefaultWebStack"/> P*>V6SK>b
ioggD
<action name="listUser" !_@%/I6
D_Y;N3E/rS
class="com.adt.action.user.ListUser"> FWg7e3
<param Y{KJk'xN5W
-MjRFa
name="page.everyPage">10</param> KVuv%?
<result 0NxaQ`\
(Gcl,IW
name="success">/user/user_list.jsp</result> cc[w%jlA#
</action> yWzTHW`)Mr
Zu,f&smb
</package> *D,T}N
E'Bt1u
</xwork> .
fIodk
H|Ems}b
isjkfl-!
]l%j>Vb!L
{F j`'0Xu;
G;e}z&6<k
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 C1=[\c~jw
(k?OYz]c
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。 PsLCO(26
!ZRV\31%
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 iQKfx#kt
h>wU';5#f
bm;4NA?Gg
]9' \<uR
Ev%\YI!MaY
我写的一个用于分页的类,用了泛型了,hoho <