Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 iII%!f?{[
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 6ZXRb
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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 {XXnMO4uR;
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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 $F/xv&t
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。 <pFbm
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分页支持类: O^~nf%
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java代码: MbQ%'z6D
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package com.javaeye.common.util; (V}?y:)
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import java.util.List; xd`\Ai
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publicclass PaginationSupport { |lIgvHgg
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publicfinalstaticint PAGESIZE = 30; U]M5&R=?
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privateint pageSize = PAGESIZE; Eh *u6K)Z
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privateList items; ?%T]V+40
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privateint totalCount; =+4om*
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privateint[] indexes = newint[0]; F\<{:wu
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privateint startIndex = 0; 0.~s>xXp
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public PaginationSupport(List items, int !H zJ*
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totalCount){ i@=(Y~tD`
setPageSize(PAGESIZE); Xk :_aJ
setTotalCount(totalCount); a!&<jM
setItems(items); wk2Ff*&
setStartIndex(0); &!>.)I`
} <Ug1g0.
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public PaginationSupport(List items, int 2FM}"g<8
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totalCount, int startIndex){ G,b*Qn5#
setPageSize(PAGESIZE); cj|Urt
setTotalCount(totalCount); EiPOY'
setItems(items); C jz(-018
setStartIndex(startIndex); nKch:g
} 6"2IV
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public PaginationSupport(List items, int W#L/|K!S
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totalCount, int pageSize, int startIndex){ ( n!8>>+1C
setPageSize(pageSize); 2}9M7Z",2
setTotalCount(totalCount); As|e=ut(
setItems(items); =pb ru=/
setStartIndex(startIndex); Nfd'|#
} nYTPcT4x|
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publicList getItems(){ I9sQPa
return items; .bNG:y>
} we33GMxHl`
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publicvoid setItems(List items){ cE*d(g
this.items = items; B*}:YV
} 2GRv%:rZ
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publicint getPageSize(){ NqN}] nu6
return pageSize; K#x|/b'5d
} WS\Ir-B
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publicvoid setPageSize(int pageSize){ o}Q3mCB
this.pageSize = pageSize; *dxE
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} l-8rCaq&J
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publicint getTotalCount(){ B#o6UO\
return totalCount; $g
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} :;w#l"e7<
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publicvoid setTotalCount(int totalCount){ 4
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if(totalCount > 0){ ufocj1IU
this.totalCount = totalCount; 4V'HPD>=V
int count = totalCount / be
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pageSize; =F46v{la
if(totalCount % pageSize > 0) lB
count++; RVh{wg
indexes = newint[count]; Lwo9s)j<e
for(int i = 0; i < count; i++){ YLb$/6gj6
indexes = pageSize * 6P02=
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i; !WTL:dk
} ?DKY;:dZF
}else{ xks Me
this.totalCount = 0; 2k^'}7G%
} |Zdl[|kX
} [G"Va_A8
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publicint[] getIndexes(){ yVyh\u\
return indexes; C ~04#z_$
} A(+%DZ
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publicvoid setIndexes(int[] indexes){ [=^Wj`;
this.indexes = indexes; a2eE!I
} ,hE989x<iI
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publicint getStartIndex(){ nNh5f]]
return startIndex; @el
} pz]!T'
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publicvoid setStartIndex(int startIndex){ 6K^O.VoV^J
if(totalCount <= 0) wQ81wfr1:
this.startIndex = 0; No*[@D]g
elseif(startIndex >= totalCount) H`rd bE
this.startIndex = indexes aAgQ^LY
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[indexes.length - 1]; '%y;{,g*
elseif(startIndex < 0) `pqTiV
this.startIndex = 0; KY\=D 2m
else{ !i\ gCLg2_
this.startIndex = indexes +tJ 7ZR%
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[startIndex / pageSize]; $4BvDZDk`B
} x7/";L>
} @I#uv|=N
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publicint getNextIndex(){ dj{~!}
int nextIndex = getStartIndex() + bbT$$b-
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pageSize; P=Su)c
if(nextIndex >= totalCount) z#2n+hwE
return getStartIndex(); R$;TX^r'o&
else )T^xDx
return nextIndex; `i<Z<
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} ?@;#|^k9
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publicint getPreviousIndex(){ U_WO<uhC
int previousIndex = getStartIndex() - IRTD(7"oyp
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pageSize; pj7v{H +
if(previousIndex < 0) 1:J+`mzpl
return0; IL`=r6\
else 6w[EJ;=p_
return previousIndex; wOsg,p;\'
} I{=Yuc
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} gyuBmY
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抽象业务类 1x%B`d
java代码:
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/** L@Q+HN
* Created on 2005-7-12 8 [D"
*/ qw{`?1[+
package com.javaeye.common.business; x_r*<?OZ
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import java.io.Serializable; B<0Kl.V
import java.util.List; Sb(OG 6
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import org.hibernate.Criteria; -gUp/#l1
import org.hibernate.HibernateException; %Aqf=R_^
import org.hibernate.Session; $lq.*UQ;0
import org.hibernate.criterion.DetachedCriteria; SmIcqM
import org.hibernate.criterion.Projections; 4]6-)RHFB
import +}PN+:yV
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org.springframework.orm.hibernate3.HibernateCallback; +wxsAGy_j
import c94=>p6
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org.springframework.orm.hibernate3.support.HibernateDaoS ?'_6M4UKa
jcb&h@T8kv
upport; |gIE$rt-~W
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import com.javaeye.common.util.PaginationSupport; mhy='AQJ
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public abstract class AbstractManager extends vrcIwCa
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HibernateDaoSupport { w 5?D]u
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privateboolean cacheQueries = false; eW;3ko E
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privateString queryCacheRegion; "c|Rpzs[
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publicvoid setCacheQueries(boolean A\#z<h[>
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cacheQueries){ YV!hlYOBi
this.cacheQueries = cacheQueries; 2;0eW&e
} I2Imb9k~B
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publicvoid setQueryCacheRegion(String cnI5G!
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queryCacheRegion){ ^39lUKL
this.queryCacheRegion = : ^("L,AF
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queryCacheRegion; =4l @A>
} )BvMFwQG
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publicvoid save(finalObject entity){ kguZ AO6
getHibernateTemplate().save(entity); +@~WKa
} aU^6FI
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publicvoid persist(finalObject entity){ U7?v4O]D[
getHibernateTemplate().save(entity); 0Qq<h;8xEc
} .ESvMK~x
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publicvoid update(finalObject entity){ %qiVbm0
getHibernateTemplate().update(entity); &*%x]fQ@
} tW/g0lC%
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publicvoid delete(finalObject entity){ @XXPJq;J
getHibernateTemplate().delete(entity); WgqSw%:$H
} RB4 +"QUh
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publicObject load(finalClass entity, (:HT|gKoE
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finalSerializable id){ 23WrJM!2N
return getHibernateTemplate().load .7
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(entity, id); &9fQW?Czs
} ?_i>Kx
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publicObject get(finalClass entity, *=.~PR6W{
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finalSerializable id){ owQ,op#
return getHibernateTemplate().get /Pkz3(1
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(entity, id); sQac%.H;`U
} dC{dw^
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publicList findAll(finalClass entity){ [`t ;or
return getHibernateTemplate().find("from C5 Q!_x(
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" + entity.getName()); 6]Is"3ca
} ^n(FO,8c
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publicList findByNamedQuery(finalString nqm=snh
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namedQuery){ UZ2_FP
return getHibernateTemplate (8)9S6
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().findByNamedQuery(namedQuery); ?'z/S5&j
} CV.|~K0O
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publicList findByNamedQuery(finalString query, Xt<1b
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finalObject parameter){ %DYh<U4N
return getHibernateTemplate wlJi_)!
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().findByNamedQuery(query, parameter); )q-NE)
} T\uIXL?3
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publicList findByNamedQuery(finalString query, _huJ*W7lR
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finalObject[] parameters){ E|"SMA,
return getHibernateTemplate KE~Q88s
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().findByNamedQuery(query, parameters); uR5+")r@S
} hm! J@
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publicList find(finalString query){ SL- 2 ^\R
return getHibernateTemplate().find HS/.H,X
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(query); TA-2{=8
} :LY.C<8
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publicList find(finalString query, finalObject "u!gfG?oH
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parameter){ ?J2A1iuq3
return getHibernateTemplate().find kt2_WW[
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(query, parameter); #0aBQ+_8H
} eTvWkpK+
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public PaginationSupport findPageByCriteria "Zgwe,#
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(final DetachedCriteria detachedCriteria){ hbH~Ya=+S
return findPageByCriteria *v+l,z4n
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); ]yf?i350
} kk-<+R2
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public PaginationSupport findPageByCriteria 7qB4_
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(final DetachedCriteria detachedCriteria, finalint +9b{Y^^~T
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startIndex){ >nghFm
return findPageByCriteria S@HC$
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(detachedCriteria, PaginationSupport.PAGESIZE, |NZi2Bu
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startIndex); Wn(!6yid
} U]sAYp^$
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public PaginationSupport findPageByCriteria ~{/M_
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(final DetachedCriteria detachedCriteria, finalint f[k#Znr
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pageSize, q5SPyfE[
finalint startIndex){ *=!e,
return(PaginationSupport) noxJr/A]
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getHibernateTemplate().execute(new HibernateCallback(){ _Hv+2E[4Z
publicObject doInHibernate PR.3EL
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(Session session)throws HibernateException { Q%JI-&K
Criteria criteria = ~Kw#^.$3T
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detachedCriteria.getExecutableCriteria(session); #{q.s[g*+1
int totalCount = d2`g,~d
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((Integer) criteria.setProjection(Projections.rowCount XGx[Ny_A2
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()).uniqueResult()).intValue(); \FVfV`x
criteria.setProjection \"a{\E,{;
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(null); q*3OWr
List items = {JgY-#R?{(
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criteria.setFirstResult(startIndex).setMaxResults WPL@v+
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(pageSize).list(); Jp=fLo 9
PaginationSupport ps = F}nwTras
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new PaginationSupport(items, totalCount, pageSize, H#SQ>vyAV
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startIndex); !{lH*
return ps; c
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} l*1|B3#m!
}, true); @L3XBV2
} T$%|=gq
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public List findAllByCriteria(final al9wNtMT
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DetachedCriteria detachedCriteria){ YExgUE|
return(List) getHibernateTemplate l^lb ^"o
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().execute(new HibernateCallback(){ pZnp!!G
publicObject doInHibernate D<S C
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(Session session)throws HibernateException { MUrPr
Criteria criteria = h@Q^&%w
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detachedCriteria.getExecutableCriteria(session); S[Du
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return criteria.list(); j7~FR{:j
} *jlIV$r_
}, true); UHZuH?|@
} 5'} V`?S
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public int getCountByCriteria(final v-{g
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DetachedCriteria detachedCriteria){ entU+O r
Integer count = (Integer) )E}v~GW.+
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getHibernateTemplate().execute(new HibernateCallback(){ ]||b2[*
publicObject doInHibernate ))"gWO
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(Session session)throws HibernateException { ;]dD\4_hK
Criteria criteria = 'C[tPP
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detachedCriteria.getExecutableCriteria(session); N''QQBUD
return yKc-:IBb{u
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criteria.setProjection(Projections.rowCount b[74$W{
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()).uniqueResult(); rW{!8FhI
} .IeO+RDQ
}, true); bKQho31a'
return count.intValue(); M-o'`e'
} WMB%?30
} &$MC!iMh
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用户在web层构造查询条件detachedCriteria,和可选的 @aIgif+v
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 cLtVj2Wb
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PaginationSupport的实例ps。 39X~<\&'
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ps.getItems()得到已分页好的结果集 J&xZN8jW
ps.getIndexes()得到分页索引的数组 .GrOdDK$ns
ps.getTotalCount()得到总结果数 `/8@Fj
ps.getStartIndex()当前分页索引 Un6R)MVT
ps.getNextIndex()下一页索引 2JfSi2T
ps.getPreviousIndex()上一页索引 n7Ao.b%uk-
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 QaWS%0go
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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
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一下代码重构了。 y*
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我把原本我的做法也提供出来供大家讨论吧: ula-o)S
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首先,为了实现分页查询,我封装了一个Page类: 5UEZpxnv
java代码: /v{+V/'+
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/*Created on 2005-4-14*/ &,nv+>D
package org.flyware.util.page; wI%M3XaBws
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/** i^s Vy
* @author Joa S6~y!J6Ok4
* nS+Rbhs
*/ ;ArwEzo(
publicclass Page { CFtQPTw
}%wd1`l7
/** imply if the page has previous page */ 3lP;=*m.
privateboolean hasPrePage; 'a~@q~!
~ ld.I4
/** imply if the page has next page */ 2dn^K3
privateboolean hasNextPage; 7({)ou x
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/** the number of every page */ -C=0Pg]ga
privateint everyPage; `[/#,*\
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/** the total page number */ U&^q#['
privateint totalPage; #AD_EN9
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/** the number of current page */ n
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privateint currentPage; ?@64gdlwq
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/** the begin index of the records by the current eaw!5]huu
^m\o(R
query */ Kd\0nf6
privateint beginIndex; 1/DtF
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/** The default constructor */ @C;1e7
public Page(){ i)i>Ulj*i
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!
} !<[+u
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/** construct the page by everyPage !>`Q]M`
* @param everyPage mF7Ak&So^
* */ G~9m,l+
public Page(int everyPage){ ]2AOW}=
this.everyPage = everyPage; I Xc `Ec
} 0z8(9DlTc
MB]E[&Q!
/** The whole constructor */ 8lyIL^
public Page(boolean hasPrePage, boolean hasNextPage, bWe2z~dP
w\buQ6pR)
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int everyPage, int totalPage, MO`Y&<g~A
int currentPage, int beginIndex){ \/
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this.hasPrePage = hasPrePage; U8_{MY-9}
this.hasNextPage = hasNextPage; hRkCB
this.everyPage = everyPage; |$Yk)z3
this.totalPage = totalPage; sI>w#1.m/&
this.currentPage = currentPage; 0seCQANd
this.beginIndex = beginIndex; g6M>S1oOO
} N?\X2J1
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/** <A3%182
* @return ni;_Un~
* Returns the beginIndex. K~(RV4oF8B
*/ DUOoTlp
publicint getBeginIndex(){ 8}QM~&&.
return beginIndex; sW>%mnx
} fc#9e9R
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/** x9lA';})
* @param beginIndex AL]gK)R
* The beginIndex to set. .$U,bE
*/ QV|6"4\
publicvoid setBeginIndex(int beginIndex){ H%_^Gy8f
this.beginIndex = beginIndex; q"d9C)Md
} 8hGyh#
y_X6{}Ke
/** oz!)x\m*H
* @return SmXoNiM"y
* Returns the currentPage. VU3RFl
*/
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publicint getCurrentPage(){ *>m[ZJd %=
return currentPage; ~Ztn(1N
} +k`L8@a3&
KzHN|8$o
/** @Q1!xA^S
* @param currentPage 8JLf @C:
* The currentPage to set. J0sD?V|{1~
*/ -P]O t>%S
publicvoid setCurrentPage(int currentPage){ i/>k_mG$d
this.currentPage = currentPage; hh;kBv07o
} )5|9EXh
u>>|ZPe
/** 3vrVX<_
* @return **q8vhJM
* Returns the everyPage. @?B+|*cm
*/ h,LSqjf"
publicint getEveryPage(){ 5U84*RY
return everyPage; U,rI/'
} J(1Tl
d)
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/** jcCAXk055
* @param everyPage b4L7M1l
* The everyPage to set. 54$^ldD
*/ "P !
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publicvoid setEveryPage(int everyPage){ ,%pCcM)
this.everyPage = everyPage; [@i:qB>B
} >.<VD7p
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/** H/a gt
* @return eMGJx "a
* Returns the hasNextPage. z}vT8qoX
*/ K V5
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publicboolean getHasNextPage(){ W8W7<ml0A
return hasNextPage;
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} ()lgd7|+
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/** ^".OMS"!
* @param hasNextPage m?S;sew@5
* The hasNextPage to set. rm-d),Zt
*/ M=,pn+}y>
publicvoid setHasNextPage(boolean hasNextPage){ XYU5.
this.hasNextPage = hasNextPage; V.B@@ ;
} 6uE20O<z]
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/** 0["93n}r
* @return 9#DXA}
* Returns the hasPrePage. %A zy#m
*/ yZlT#^$\
publicboolean getHasPrePage(){ Nd0tR3gi7
return hasPrePage; Nm)3
} q1ysT.{p,
juEPUsE
/** Q<sqlh!h
* @param hasPrePage J2O,wb)U
* The hasPrePage to set. KjGu !B
*/ a>j}@8[J
publicvoid setHasPrePage(boolean hasPrePage){ Us`=^\
this.hasPrePage = hasPrePage;
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} u^MKqI
~&Z>fgOTJ
/** J3yK^@&&
* @return Returns the totalPage. e#[Klh$]EW
* s^u Y
*/ "7cty\
publicint getTotalPage(){ -XYvjW,|
return totalPage; D07M!U
} z:Am1B
~"+"6zg
/** 1EU4/6!C
* @param totalPage _=g&^_ #t
* The totalPage to set. %a/3*vz/I%
*/ /A9RmTb
publicvoid setTotalPage(int totalPage){ 8lQ}-8
this.totalPage = totalPage; 5kHaZ Q
} 217G[YE-
=j>xu|q
} x80IS:TP
%+*=Vr
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*'((_NZ>
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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 ny-:%A
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个PageUtil,负责对Page对象进行构造: aUw-P{zp%
java代码: "L3mW=!*
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/*Created on 2005-4-14*/ 53t_#Yte
package org.flyware.util.page; ,`t+X=#
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import org.apache.commons.logging.Log; s#?ZwD,=
import org.apache.commons.logging.LogFactory; sK2N3B&6
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/**
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* @author Joa R"W}\0k
*
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*/
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publicclass PageUtil { REW[`MBQ
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privatestaticfinal Log logger = LogFactory.getLog !q\8`ss
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(PageUtil.class); @7 Ry{,A
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/** bYsX?0T!p
* Use the origin page to create a new page Y4k2=w:D
* @param page T;6M UmyC
* @param totalRecords ?.e,NHf
* @return t/;2rIx>
*/ v@qP &4Sp
publicstatic Page createPage(Page page, int XPd mz !,b
kqBZsfF
totalRecords){ U3_${
return createPage(page.getEveryPage(), -8l<5g7
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page.getCurrentPage(), totalRecords); <r}wQ\F#
} vT?^#
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/** ?i _ACKpw
* the basic page utils not including exception Z"8lW+r*
yd;e;Bb7*
handler #RlZxtx.O
* @param everyPage :a }](Wn
* @param currentPage T.da!!'B
f
* @param totalRecords wv9HiHz8gD
* @return page !v}TRGX
*/ 8^>qor.]M
publicstatic Page createPage(int everyPage, int /2p*uv}IP
) H,Xkex
currentPage, int totalRecords){ = wz}yfdrC
everyPage = getEveryPage(everyPage); g~DuK|+
currentPage = getCurrentPage(currentPage); | N/d}
int beginIndex = getBeginIndex(everyPage, httywa^
v]k-xn|$j
currentPage); a0|hLqI
int totalPage = getTotalPage(everyPage,
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ea=E/HR-
totalRecords); _,drOF|e
boolean hasNextPage = hasNextPage(currentPage, s+:|b~
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totalPage); afrF%!
boolean hasPrePage = hasPrePage(currentPage); `;85Mo:qJ
w9'>&W8T
returnnew Page(hasPrePage, hasNextPage, Mq\=pxC@
everyPage, totalPage, hhU_kI
currentPage, D7hTn@I
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beginIndex); Go%Z^pF3CO
} VM$n|[C~
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privatestaticint getEveryPage(int everyPage){ 6ld4'oM
return everyPage == 0 ? 10 : everyPage; ">[#Ops-;$
} *D|a`R!Y
WZ' Z"'
privatestaticint getCurrentPage(int currentPage){ 1Dr&BXvf]8
return currentPage == 0 ? 1 : currentPage; 7( 84j5zb
} W\l&wR
YYQvt
privatestaticint getBeginIndex(int everyPage, int F{x+1hct0
sa'1hX^@
currentPage){ /"X_{3dq?
return(currentPage - 1) * everyPage; x0# Bc7y
} 0=>$J
WF
Qj^Uz+b
privatestaticint getTotalPage(int everyPage, int CV0id&Nv
Lap?L/NS
totalRecords){ %Y&48''"
int totalPage = 0; Bt<)1_
j!4{+&Laq
if(totalRecords % everyPage == 0) X /c8XLe"
totalPage = totalRecords / everyPage; I# tlaz#
else -DkD*64wu
totalPage = totalRecords / everyPage + 1 ; X$!fR >Zc
x17:~[c']
return totalPage; HTL6;87w+]
} ':n`0+Eh
e0(/(E:
privatestaticboolean hasPrePage(int currentPage){ ov+{<0Q
return currentPage == 1 ? false : true; Wep^He\:
} 'maX
9VW/Af
privatestaticboolean hasNextPage(int currentPage, ek&~A0k_o
|.@!CqJ
int totalPage){ ZXx1S?u
return currentPage == totalPage || totalPage == uZld9u
%6[,a
0 ? false : true; "}71z
} =f~<*wQ
aBC5?V*e%
4v_Ac;2m&
} wa[L[mw
s~7a-J
DXf
"1,*6(;:
9 :2Bt <q
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。 IP`lx
OH/9<T?
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 :A8r{`R'N
*J4!+GD
做法如下: KtaoOe
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 af|h4.A
L -Q8iFW'
的信息,和一个结果集List: Sqa9+'
[
java代码: 5qM$ahN3wH
lc
<V_8
:of([e|u6
/*Created on 2005-6-13*/ @1oX
package com.adt.bo; [l-o*@
N[cIr{XBGN
import java.util.List; +mrLMbBiD
6) i-S<(
import org.flyware.util.page.Page; Ovx
*
neU=1socJ
/** p<r^{y
* @author Joa ^t3>Z|DiB^
*/ '@Uu/~;h
publicclass Result { Q>$B.z
OkC.e')Vx
private Page page; vhF9|('G
fnX[R2KZ
private List content; fd4gB6>
B :%Vq2`
/** 43k'96[2d
* The default constructor l0'Yq%Nf
*/ Nk@-yZ@,8
public Result(){ Mst%]@TG
super(); [0Xuo
} GFT@Pqq
_S) K+C|@
/** R([zlw~B5
* The constructor using fields /%cDX:7X
* *Hx*s_F
* @param page FF#Aq
* @param content IFBt#]l0
*/ (wL$h5SG
public Result(Page page, List content){ u0#KBXRo
this.page = page; wnC-~&+6
this.content = content; eZ:iW#YF
} u43Mo\"<&%
Ct'tUF<K5
/** n>)aw4
* @return Returns the content. &vmk!wAs
*/ ,Mw93Kp
Va
publicList getContent(){ WdOxwsq"
return content; (RI)<zaK
;
} %ap]\o$^4
$*eYiz3Ue
/** [CEV&B
* @return Returns the page. "3VX9{'%@
*/ qoZi1,i'
public Page getPage(){ s O#cJAfuu
return page; bqH
[-mu6
} d3z nb@7
ovN3.0tAI
/** HsYzIQLL
* @param content |"K%Tvxe
* The content to set. $W|JQ h
*/ ,~cK]!:>s
public void setContent(List content){ 6Mk#) ebM
this.content = content; ; s(bd#Q
} sq=EL+=j
b;
of9hY
/** Hx6ODj[-
* @param page ]0'cdC
* The page to set. r??_2>Q
*/ jUE:QOfRib
publicvoid setPage(Page page){ >h8m8J
this.page = page; J,,VKA&
} 9U;
} "<|KR{/+
@N '_qu
u)h
{"pP
@MibKj>o
_v#puFy
2. 编写业务逻辑接口,并实现它(UserManager, egs P\ '
@"s<0T^H
UserManagerImpl) b$;oty9Y
java代码: UA'bE~i
o`,}b1lh
*i*\dl
/*Created on 2005-7-15*/ lO\HchGzB
package com.adt.service; WCd:(8B
+E9G"Z65iP
import net.sf.hibernate.HibernateException; &M5v EPR
GTB\95j]
import org.flyware.util.page.Page; }],l m
&wU"6E
import com.adt.bo.Result; (!@gm)#h
^}2!fRKAmo
/** Up%XBA
* @author Joa KPy)%i
*/ (@NILK
publicinterface UserManager { q/:]+
&p#PYs|H
public Result listUser(Page page)throws zU[o_[+7^
dlyGgaV*X
HibernateException; kT
*b~8`Opa`
} 8r>\scS
jhz*Y}MX
)j'Qi^;(D
/*gs]
{QG6ldI
java代码: N1Xg-u?ul#
i9 CQ~
zdem}kBIe
/*Created on 2005-7-15*/ @G]*]rkKb
package com.adt.service.impl; 2Rys:$
enxb
pq#
import java.util.List; Wk^{Tn/]
+uF}mZS^
import net.sf.hibernate.HibernateException; \a0{9Xx F
|{|B70v3Co
import org.flyware.util.page.Page; R7b-/
!L
import org.flyware.util.page.PageUtil; OE[7fDe'
5X3JQ"z
import com.adt.bo.Result; tHaHBx1P
import com.adt.dao.UserDAO; bkR~>F]FAu
import com.adt.exception.ObjectNotFoundException; [ {"x{;
import com.adt.service.UserManager; R%LFFMVn
&b~X&{3,
/** cb'Ya_
* @author Joa s8:epcL`A
*/ Msvs98LvW
publicclass UserManagerImpl implements UserManager { ai/]E6r
dR i6
private UserDAO userDAO; xxzUey
f
} r
\
/** 2ia&c@P-
* @param userDAO The userDAO to set. Q2oo\
*/ 8MW-JZ
publicvoid setUserDAO(UserDAO userDAO){ g#fn( A
this.userDAO = userDAO; 4T52vM
} )M.g<[=^
q%bFR[p<*
/* (non-Javadoc) (Of`VT3ZOA
* @see com.adt.service.UserManager#listUser 8S#&XS>o
P$Yw'3v/
(org.flyware.util.page.Page) V4u4{wU]
*/ rVhfj~Ts
public Result listUser(Page page)throws (e_p8[x
VxOWv8}|
HibernateException, ObjectNotFoundException { gs0jwI
int totalRecords = userDAO.getUserCount(); 1Cc91
if(totalRecords == 0) /xSJljexz
throw new ObjectNotFoundException Q7`)&^
Hx
@)MG&X
("userNotExist"); jB9~'>JY
page = PageUtil.createPage(page, totalRecords); &B:L9^
List users = userDAO.getUserByPage(page); [+5g 9tBJ
returnnew Result(page, users); lO9Ixhf~iu
} *Q2 oc:6
_UP 9b@Z"
} /Xc9}~t6
1fJ~Wp @1
a{^2c!
[ Ous|a[)o
+MYrNR.p
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 5s%e9x|kP
cJ?,\@uuP
询,接下来编写UserDAO的代码: F W2x
3. UserDAO 和 UserDAOImpl: (!m6>m2
java代码: < j
g<DXJ7o
:Eh}]_
/*Created on 2005-7-15*/ GXLh(d!C
package com.adt.dao; uZf
6W<a
~tL:r=
import java.util.List; B<myt79F_[
JSq3)o9?/
import org.flyware.util.page.Page; REcKfJTj
bFG?mG:
import net.sf.hibernate.HibernateException; {[bpvK
pi70^`@ 'B
/** [Djx@x
* @author Joa | Wj=%Ol%o
*/ '8R5Tl
publicinterface UserDAO extends BaseDAO { $AZ=;iP-
zZ Y1E@~
publicList getUserByName(String name)throws s7jNRY V
fhdqes])
HibernateException; rT-.'aQ2t
t0xE
publicint getUserCount()throws HibernateException; W}7Uh
b
6o]{< T/'
publicList getUserByPage(Page page)throws ',|OoxhbK
Ma{@b$>
HibernateException; ETH
($$M
y_Gs_xg
} 2S:B%cj9m
m'G=WO*%
mJ[_q>
RV]QVA*i
U![$7k>,pr
java代码: Dbx zqd
n0K+/}m
J_XkQR[Y
/*Created on 2005-7-15*/ B1I{@\z0G
package com.adt.dao.impl; @yQ1F>
t
xU{0rM"
import java.util.List; dB&<P[$+8
FKe/xz
import org.flyware.util.page.Page; ,T^A?t
())_4 <
import net.sf.hibernate.HibernateException; !Dc;R+Ir0!
import net.sf.hibernate.Query; I"8Z'<|/\q
~rq:I<5
import com.adt.dao.UserDAO; p_zVrlVb
V%t_,AT
/** 'F*OlZ!BWy
* @author Joa fS8Pi,!
*/ uHZjpMoM
public class UserDAOImpl extends BaseDAOHibernateImpl ~U ]%>Zf
]A+t@/k
implements UserDAO { EronNtu8i
X=Y(,ZR(&
/* (non-Javadoc) C=K{;.
* @see com.adt.dao.UserDAO#getUserByName 1n*"C!q
bz,"TG[
(java.lang.String) =_6 Q26
*/ yk^2<?z>2
publicList getUserByName(String name)throws #K` [XA
JvCy&xrE;
HibernateException { [H$kVQC
String querySentence = "FROM user in class c>r~pY~$
b;vVlIG
com.adt.po.User WHERE user.name=:name"; 2>J;P C[;
Query query = getSession().createQuery XfEp_.~JM
y+7+({w<
(querySentence); R+U*]5~R
query.setParameter("name", name); uTl"4;&j
return query.list(); ,Cy&tRjR B
} m<;MOS
ulEtZ#O{_
/* (non-Javadoc) 3+C;zDKa
* @see com.adt.dao.UserDAO#getUserCount() LR4W
*/ n(n7"+B
publicint getUserCount()throws HibernateException { #!m^EqF1_
int count = 0; *uxKI:rB:
String querySentence = "SELECT count(*) FROM >r4BI}8SK<
u2':~h?l
user in class com.adt.po.User"; c*(=Glzn
Query query = getSession().createQuery V6Of(;r
b
ts*qx&)
(querySentence); PKGqu,J,
count = ((Integer)query.iterate().next )1YGWr;ykS
UpiZd/K
()).intValue(); ds2xl7jg
return count; gxVJH'[V5
} e9CvdR
qr*e9Uk^
/* (non-Javadoc) HuxvIg
* @see com.adt.dao.UserDAO#getUserByPage 'I[xZu/8yg
^R+CkF4l l
(org.flyware.util.page.Page) ZxDh!_[s
*/ {=Py|N\\t
publicList getUserByPage(Page page)throws pUgas?e&
i1HO>X:ea
HibernateException { 27F:-C~.9
String querySentence = "FROM user in class J3r':I}\
JvJ)}d$,&
com.adt.po.User"; 5a&gdqg]
Query query = getSession().createQuery V Kc`mE
O=u.J8S2
(querySentence); :19s=0
query.setFirstResult(page.getBeginIndex()) {D]I[7f8Ev
.setMaxResults(page.getEveryPage()); N B8Yn\{B
return query.list(); u)D!Rh V&
} \ov]Rn
SS;'g4h\6
} +~;#!I@Di
!_&;#j](
1@+&6UC
mm
|*
(tg+C\
S.
至此,一个完整的分页程序完成。前台的只需要调用 Wx8cK=
LH~
t5
userManager.listUser(page)即可得到一个Page对象和结果集对象 +:J:S"G
S!
.N3ezn
的综合体,而传入的参数page对象则可以由前台传入,如果用 On@p5YRwW
{#+'T 13sx
webwork,甚至可以直接在配置文件中指定。 G<~P||Lu^
I%0J=V;o{
下面给出一个webwork调用示例: #vR5a}BAk
java代码: %nkbQ2^
7l'1
?CpM.{{s
/*Created on 2005-6-17*/ NL"w#kTc()
package com.adt.action.user; ;tZ 8Sh)
{Q0DHNP(G
import java.util.List;
Bf,}mCq
n+'s9
import org.apache.commons.logging.Log; t.7_7`bin~
import org.apache.commons.logging.LogFactory; $bk_%R}s
import org.flyware.util.page.Page; A&Q!W)=
Ez>!%Hpn\
import com.adt.bo.Result; sgB|2cj;j
import com.adt.service.UserService; l-'\E6grdH
import com.opensymphony.xwork.Action; ?&b"/sRS
z)*\njYe
/** 1| xKb(_l
* @author Joa KeC&a=HL
*/ YgkQF0+
publicclass ListUser implementsAction{ ksqb& ux6
fp"GdkO#}i
privatestaticfinal Log logger = LogFactory.getLog R1:7]z0B
x=1Sbs w{
(ListUser.class); t3.I ` Z
i32S(3se
private UserService userService; rT{2
CyJZip
private Page page; T"Nnl(cO_
xQzXl
privateList users; @])}+4D(S
35SL*zS@-
/* 'G3|PA7v
* (non-Javadoc) X'cm0}2
* ~rbJtz
* @see com.opensymphony.xwork.Action#execute() p;vrPS
*/ Olq`mlsK
publicString execute()throwsException{ liH1r1M
Result result = userService.listUser(page); p/jAr+XM
page = result.getPage(); 9Cw !<
users = result.getContent(); v/G^yZa
return SUCCESS; ?? Dv\yLZI
} Ozc9y y!%
ze#ncnMo
/** M`@Es#s
* @return Returns the page. AyMbwCR"X
*/ `?vI_>md'!
public Page getPage(){ MAG/7T5
return page; i
th!,jY*i
} 1++ Fs
atfK?VK#
/** #r80FVwiD
* @return Returns the users. ?h ym~,
*/ +D#.u^
publicList getUsers(){ koT: r
return users; ;0E[ ;
L!
} yTU'voE.|
$s5D/60nO
/** <D(|}5qR
* @param page ~fly6j|u
* The page to set. ltmD=-]G_
*/ 9B1bq #
publicvoid setPage(Page page){ [AAIBb+U
this.page = page; ; HjT
} 2v1dSdX,W
6NzS <
/** #4?:4Im#
* @param users U{-[lpd
* The users to set. c}#(,<8X
*/ qk\LfRbj
publicvoid setUsers(List users){ ig:z[k?
this.users = users; \&%y4=y<sE
} 7o`pNcabtz
PAy7b7m~B
/** .h;X5q1
* @param userService <p8>"~R
* The userService to set. `k'Dm:*`u4
*/
B*Q
publicvoid setUserService(UserService userService){ C=PV-Ul+
this.userService = userService; +Ram%"Zwh
} /Oa.@53tK6
} %'[ pucEF
e#{l
U\", !S~<
w'!J
ju;Myi}a
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, IHf#P5y_
29h_oNO
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 fuA8jx
gd\b]L?>O
么只需要: m_>~e}2'A
java代码: T
^z Mm
O6r.q&U
k.w}}78N2N
<?xml version="1.0"?> m?Dk(DJ
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork |0aGX]Y
.1?7)k
v
1.0//EN" "http://www.opensymphony.com/xwork/xwork- `v$Bib)
{c:ef@'U
1.0.dtd"> h5m6 )0"
wi-{&
<xwork> qt#4i.Iu+
%p.hwgvnp
<package name="user" extends="webwork- O7tL,)Vv
Nx4X1j?-n
interceptors"> }WG -R
z`rW2UO#a`
<!-- The default interceptor stack name .(8eWc YK
W/I D8+:i
--> +\`t@Ht#
<default-interceptor-ref 'O]Ja-
} =^Al;W
name="myDefaultWebStack"/> {:d9q
o[CjRQY]P
<action name="listUser" I~I$/j]e`
]%/a'[
class="com.adt.action.user.ListUser"> ]$96#}7N
<param \%:]o-+"I
>iB-gj}>X
name="page.everyPage">10</param> b'~IFNt*^
<result i3\6*$Ug
9 k>=y n
name="success">/user/user_list.jsp</result> |{@_J
</action> -)ag9{ *
H>2f M^
</package> 7Ke#sW.HN
Ty>g:#bogI
</xwork> |MXv
w6P
auT$-Ki8
o+Kh2;$)
az ?2
.Qeml4(`3
)|zna{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 0^{?kg2o_
-#?p16qz5
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。 (Eoji7U
g?caE)
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 j;b<oQH
1z[GY RSt
y:+s*x6Vg
~.w Db,*
wUz)9n 6j
我写的一个用于分页的类,用了泛型了,hoho uua1_#a
j?n:"@!G/
java代码: ,o)U9<
Q-GnNT7MB3
hq^@t6!C\m
package com.intokr.util; pJ 1Q~tI
8QGj:3
import java.util.List; |.Pl[y
A{Q :,S)
/** +tXOP|X
* 用于分页的类<br> !zNMU$p
* 可以用于传递查询的结果也可以用于传送查询的参数<br> C=/nZGG
* #TX=%x6
* @version 0.01 |O]oX[~
* @author cheng z3[0BWXs
*/ -f-2!1&<3h
public class Paginator<E> { :J}@*>c
privateint count = 0; // 总记录数 8HLcDS#
privateint p = 1; // 页编号 7E9h!<5v
privateint num = 20; // 每页的记录数 r.:H`
privateList<E> results = null; // 结果 Vhs:X~=qL
61J01(+|
/** x@]pUA1
* 结果总数 6A& f
*/ k&1~yW
publicint getCount(){ '.wyfS H@
return count; y[l19eU
} g{cHh(S
cKX6pG
publicvoid setCount(int count){ 1Bz'$u;
this.count = count; FT*
o;&_QS
} jbqhNsTNK
^Q?I8,4}
/** GBZx@B[TY
* 本结果所在的页码,从1开始 =R^V[zTn_
* ?_F,HhQ
* @return Returns the pageNo. 0F<O \
*/ w^&TG3m1~
publicint getP(){ 4{\h53j$
return p; z.[ Ok
} m
dC.M$
B94mh
/** gi7As$+E
* if(p<=0) p=1 <'4DMZ-G
*
U!-|.N,
* @param p BK'!WX
*/ Dc[Qu?]LM
publicvoid setP(int p){ 4>gMe3]0
if(p <= 0) e.0vh?{\
p = 1; B*owV%
this.p = p; y\Z-x
} 8fdK|l w
F~ n}Ep~1
/** }q( IKH\&
* 每页记录数量 iw(\]tMt
*/ :!1B6Mc
publicint getNum(){ yV xR||e
return num; ]*^mT&$7
} 5|-(Ic
G2k r~FG
/** $2^V#GWo
* if(num<1) num=1 *Df|D/,WE
*/ Y1
i!
publicvoid setNum(int num){ nFlj`k<]Y
if(num < 1) d&