Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 jQi)pVT^
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 a9niXy}a(
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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 }1?
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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 yQdoy^d/4
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分页支持类: 'G8.)eTA'
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java代码: B^lm'/,@
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package com.javaeye.common.util; U9%#(T$
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import java.util.List; NTy0NH
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publicclass PaginationSupport { Ika(ip#]=
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publicfinalstaticint PAGESIZE = 30; Yxd&hr
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privateint pageSize = PAGESIZE; d'*:2;)g^
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privateList items; qb?9i-(
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privateint totalCount; d,*#yzO
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privateint[] indexes = newint[0]; 25m!Bf
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privateint startIndex = 0; WJF#+)P:Y
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public PaginationSupport(List items, int yp\sJc`
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totalCount){ WbH#@]+DN
setPageSize(PAGESIZE); #b5V/)K
setTotalCount(totalCount); ~E*`+kD
setItems(items); ,{VC(/d
setStartIndex(0); I+g[
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} Nlk'
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public PaginationSupport(List items, int 0MX``/Z72
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totalCount, int startIndex){ ?JI:>3e
setPageSize(PAGESIZE); a534@U4,
setTotalCount(totalCount); f]37Xl%I
setItems(items); C">w3#M%
setStartIndex(startIndex); 18];fC
} EH~XN9b
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public PaginationSupport(List items, int 8}<4f|?
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totalCount, int pageSize, int startIndex){ 5&N55?G6
setPageSize(pageSize); a^QyYX}\qR
setTotalCount(totalCount); lCC(N?%Q
setItems(items); |}KNtIX\G
setStartIndex(startIndex); Jrm 9,7/
} X0e#w?
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publicList getItems(){ |)+;d
return items; g}Esj"7
} < rqFBq8
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publicvoid setItems(List items){ Kt\#|-{CH-
this.items = items; T~JE.Y3B3
} 1@vlbgLr@
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publicint getPageSize(){ F3pBk)>a\
return pageSize; L-QzC<[F/
} ;!H|0sv
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publicvoid setPageSize(int pageSize){ Cp[
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this.pageSize = pageSize; j&
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} 6|AD]/t^K
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publicint getTotalCount(){ qt{{q
return totalCount; 'mR9Uqq\
} eV)'@8p
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publicvoid setTotalCount(int totalCount){ E0-<-w3'
if(totalCount > 0){ :$gR
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this.totalCount = totalCount; Re^~8q[
int count = totalCount / K6X}d,g
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pageSize; l1MVC@'pvP
if(totalCount % pageSize > 0) l\%LT{$e
count++; Vp~c$y+
indexes = newint[count]; OPP^n-iPr
for(int i = 0; i < count; i++){ ">D7wX,.>
indexes = pageSize * [/iT D=O,
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} H(WRm1i"G
}else{ daakawn+
this.totalCount = 0; G.[,P~yy.
} i6y$P6s
} g7 r_jj%ow
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publicint[] getIndexes(){ Q>[Xm)jr:
return indexes; H 6~6hg
} |NoTw K
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publicvoid setIndexes(int[] indexes){ r#;GVJR6
this.indexes = indexes; Obb"#W@3
} do>,ELS+m
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publicint getStartIndex(){ QqU>V0y"w(
return startIndex; xJSK"
} sN%#e+(=
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publicvoid setStartIndex(int startIndex){ ]1k"'XG4,
if(totalCount <= 0) m}oqs0xx
this.startIndex = 0; .vJlTg
elseif(startIndex >= totalCount) yv2N5IQ>{V
this.startIndex = indexes aF
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[indexes.length - 1]; Sq Y$\&%
elseif(startIndex < 0) 2\/,X CQV
this.startIndex = 0; xq<3*Bcw
else{ Tb@r@j:V
this.startIndex = indexes 8nSEAr~
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[startIndex / pageSize]; jF r[T
} &?)?
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} 8M,AFZ>F
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publicint getNextIndex(){ l1?$quM^V
int nextIndex = getStartIndex() + _hz}I>G@B
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pageSize; .nG14i7C
if(nextIndex >= totalCount) K\3N_ztu
return getStartIndex(); PDi]zp9>H
else xB<^ar
return nextIndex; q<Sb>M/\,
} NZW)$c'
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publicint getPreviousIndex(){ :Ou[LF.O
int previousIndex = getStartIndex() - (<ZpT%2
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pageSize; T>cO{I
if(previousIndex < 0) Am @o}EC
return0; Xvr7qowL
else 4v?}K
return previousIndex; pcrarj
} n;+`%;6
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} j2GTo~muq
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抽象业务类 hq|I%>y
java代码: hzcSKRm
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/** t3(~aH
* Created on 2005-7-12 JLn)U4>z w
*/
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package com.javaeye.common.business; V=cJdF
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import java.io.Serializable; D<wz%*
import java.util.List; ]H$Trf:L
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import org.hibernate.Criteria; =73aME}
import org.hibernate.HibernateException; h; "pAE
import org.hibernate.Session; F+ Dke>j
import org.hibernate.criterion.DetachedCriteria; "PePiW(i+
import org.hibernate.criterion.Projections; &rbkw<=j
import %5yP^BL0
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org.springframework.orm.hibernate3.HibernateCallback; fG_<HJS(~
import ? l>Ra0
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org.springframework.orm.hibernate3.support.HibernateDaoS r"&uW!~0
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upport; %+: $uk[
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import com.javaeye.common.util.PaginationSupport; yE_T#FN
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public abstract class AbstractManager extends VYw<8AEFY
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HibernateDaoSupport { 0 H0U%x8
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privateboolean cacheQueries = false; Min{&?a
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privateString queryCacheRegion; m88(f2Ch
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publicvoid setCacheQueries(boolean [O@U@bD9
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cacheQueries){ Hg04pZupN
this.cacheQueries = cacheQueries; oH"VrS 6
} E0*62OI~O
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publicvoid setQueryCacheRegion(String !%/2^
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queryCacheRegion){ !IC@^kkh{
this.queryCacheRegion = oEJxey]B7
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queryCacheRegion; |<2<`3
} J;S Z"I'
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publicvoid save(finalObject entity){ r*kz`cJ
getHibernateTemplate().save(entity); ^~kfo|
} R+5yyk\
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publicvoid persist(finalObject entity){ ^5q}M'
getHibernateTemplate().save(entity); )CoJ9PO7
} Q6$^lRNOpk
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publicvoid update(finalObject entity){ ?.g="{5X
getHibernateTemplate().update(entity); RV>n Op}R
} :4x&B^,53
ow4|GLU^;
publicvoid delete(finalObject entity){ %4x,^ K]
getHibernateTemplate().delete(entity); Ij?Qs{V
} l9+)h}
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publicObject load(finalClass entity, xA>3]<O
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finalSerializable id){
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return getHibernateTemplate().load r"W<1Hu
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(entity, id); M!Ywjvw*)3
} \=j|ju3
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publicObject get(finalClass entity, LM*m>n*
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finalSerializable id){ ')Qb,#/,%
return getHibernateTemplate().get 7,3 g{8
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(entity, id); F$HL\y
} (G 9Ku 8Y
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publicList findAll(finalClass entity){ mMtva}=*
return getHibernateTemplate().find("from Q(BM0n)f
ch)#NHZ9F
" + entity.getName()); DcsQ 6
} B&sa|'0U
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publicList findByNamedQuery(finalString NC%)SG \
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namedQuery){ yJ2A!id
return getHibernateTemplate rW[7
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().findByNamedQuery(namedQuery); {W%/?d9m
} BFPy~5W
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publicList findByNamedQuery(finalString query, S~\u]j^%y
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finalObject parameter){ xz){RkVzP
return getHibernateTemplate @O| lA
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().findByNamedQuery(query, parameter); TL@{yJ;s
} 3gz4c1 s^:
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publicList findByNamedQuery(finalString query, fH 0&Wc3yC
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finalObject[] parameters){ |$`I1
return getHibernateTemplate | (: PX
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().findByNamedQuery(query, parameters); V]|P>>`v9p
} y2@8?
Ombvp;
publicList find(finalString query){ {3G2-$yb
return getHibernateTemplate().find }O8#4-E_Ji
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(query); ^w~Utx4
} k2DBm q;
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publicList find(finalString query, finalObject ILT.yxV
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parameter){ 3k* U/*
return getHibernateTemplate().find FQw@@
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(query, parameter); 3t$)saQR
} YCu9dBeVS
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public PaginationSupport findPageByCriteria ("_tML 8/p
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(final DetachedCriteria detachedCriteria){ -MItZ
return findPageByCriteria N}7tjk
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); LYp=o8JW|
} "hXB_73)V
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public PaginationSupport findPageByCriteria WHvxBd
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(final DetachedCriteria detachedCriteria, finalint MUqV$#4@I
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startIndex){ -,}ppTG
return findPageByCriteria 'E~[I"0
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(detachedCriteria, PaginationSupport.PAGESIZE, \7A6+[
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startIndex); *m`KY)b=l
} Auf2JH~
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public PaginationSupport findPageByCriteria wE J?Y8
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(final DetachedCriteria detachedCriteria, finalint y
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pageSize, Dv[ 35[Yh
finalint startIndex){ t"]~e"
return(PaginationSupport) %2TjG
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getHibernateTemplate().execute(new HibernateCallback(){ tS&rR0<OW
publicObject doInHibernate d=8q/]_p
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(Session session)throws HibernateException { oN
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Criteria criteria = tQrkRg(E:
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detachedCriteria.getExecutableCriteria(session); m@^!?/as
int totalCount = VJ$UpqVm
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((Integer) criteria.setProjection(Projections.rowCount PK|"+I0
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()).uniqueResult()).intValue(); -A17tC20J1
criteria.setProjection \t
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(null); Ye) F{WqZ#
List items = <X1^w
"=9kX`(1 y
criteria.setFirstResult(startIndex).setMaxResults tN:PWj5
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(pageSize).list(); V+2C!)f(
PaginationSupport ps = 9`p|>d!.
9Lv"|S`5W_
new PaginationSupport(items, totalCount, pageSize, $C8nPl' 7
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startIndex); 'vUx4s
return ps; ^z\*;
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} 6!^&]4
}, true); smN|r
} #DFfySH)A
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public List findAllByCriteria(final `@07n]KB
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DetachedCriteria detachedCriteria){ #0;ULZ99aH
return(List) getHibernateTemplate k(.6K[b
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().execute(new HibernateCallback(){ PhOtSml0
publicObject doInHibernate N9A#@c0O
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(Session session)throws HibernateException {
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Criteria criteria = d~U}IMj
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detachedCriteria.getExecutableCriteria(session); ~E tW B
return criteria.list(); U%nLo[k
} u+Q<>>lU
}, true); 6@[7
} b
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public int getCountByCriteria(final _wKaFf
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DetachedCriteria detachedCriteria){ 7; e$ sr
Integer count = (Integer) cq,0?2R`t
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getHibernateTemplate().execute(new HibernateCallback(){ e=m=IVY#W
publicObject doInHibernate BQfq]ti
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(Session session)throws HibernateException { A\v(!yg
Criteria criteria = @ = M:RA
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detachedCriteria.getExecutableCriteria(session); OEFALt
return _`(WX;sK
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criteria.setProjection(Projections.rowCount hPB^|#}
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()).uniqueResult(); d1rIU6
} 9Oe~e
}, true); q/lQEfR
return count.intValue(); 86AZ)UP2D
} Ob#d;F
} uVn"'p-
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用户在web层构造查询条件detachedCriteria,和可选的 WQ1~9#
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 t/57LjV
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PaginationSupport的实例ps。 9 cwy;au
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ps.getItems()得到已分页好的结果集 f6r~Ycf,f
ps.getIndexes()得到分页索引的数组 $ rU"Krf67
ps.getTotalCount()得到总结果数 ;"K;D@xzh]
ps.getStartIndex()当前分页索引 %7y8a`}
ps.getNextIndex()下一页索引 zG. \xmp
ps.getPreviousIndex()上一页索引 vk&6L%_~a
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 $%P?2g"j,
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 fZ5zsm'N
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一下代码重构了。 4Nun-(q
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我把原本我的做法也提供出来供大家讨论吧: #{DX*;1m
u9zEhfg8
首先,为了实现分页查询,我封装了一个Page类: -/'_XR@1
java代码: <(c_[o/
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/*Created on 2005-4-14*/ lPaTkZw
package org.flyware.util.page; =+z +`ot
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/** aVvma=
* @author Joa Id}/(Pkq
* {gkzo3
*/ bQlv b
publicclass Page { g]Jt (aYK
w5+H9R6
/** imply if the page has previous page */ + ;LO|!
privateboolean hasPrePage; Rl/5eE8
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/** imply if the page has next page */ r&y0`M
privateboolean hasNextPage; 31^Jg
qC x|}5:
/** the number of every page */ wr-/R"fX
privateint everyPage; uSgR|b;R]
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/** the total page number */ (xdC'@&
privateint totalPage; SIridZ*%
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/** the number of current page */ .US=fWyrb
privateint currentPage; ~~\C.6c#
!7hjA=0
/** the begin index of the records by the current
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e=^^TX`I
query */ 2Wn*J[5
privateint beginIndex; [p+-]V
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v8} vk]b
/** The default constructor */ uo8[,'
public Page(){ omMOA
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} ('k9X cTPP
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/** construct the page by everyPage _1,hO?TK
* @param everyPage +6`+Q2qi
* */ fg)VO6Wo&
public Page(int everyPage){ ?:42jp3
this.everyPage = everyPage; KcvstC`
} l+A)MJd oj
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/** The whole constructor */ ?Gl]O3@3
public Page(boolean hasPrePage, boolean hasNextPage, "qrde4O
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@ tvz9N
int everyPage, int totalPage, g&*,j+$ }
int currentPage, int beginIndex){ awv$ }EFo
this.hasPrePage = hasPrePage; `FGYc
this.hasNextPage = hasNextPage; {sfA$ d0
this.everyPage = everyPage; )Yu
this.totalPage = totalPage; er8T:.Py
this.currentPage = currentPage; \i'Z(1
this.beginIndex = beginIndex; k-Yli21-/|
} 'eo/"~/*w
;,}Dh/&E
/** Z%Fc
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* @return Qhq' %LR
* Returns the beginIndex. 3_ly"\I\
*/ "ze-Mb
publicint getBeginIndex(){ ;_=N
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return beginIndex; PU,%Y_xR
} UCt}\IJ
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/** )qRH?Hsb7
* @param beginIndex Vel}lQD
* The beginIndex to set. %s! |,Cu
*/ f{.4#C'
publicvoid setBeginIndex(int beginIndex){ ;1HzY\d%<
this.beginIndex = beginIndex; q6,z 1A"
} |h?2~D!+d
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/** 4*ZY#7h
* @return .ht-*
* Returns the currentPage. M!46^q~-
*/ :sQ>oNnz
publicint getCurrentPage(){ _U_O0@xi
return currentPage; !Ii[`H
} hvG D`
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/** 9Pb6Z}
* @param currentPage L#",.x
* The currentPage to set. :r(dMU3%
*/ nwp(% fBo
publicvoid setCurrentPage(int currentPage){ wFX9F3m
this.currentPage = currentPage; Gl@{y (
} UE{$hLI?g
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/** Mf2F LrAh
* @return q3<kr<SP
* Returns the everyPage. En:>c
*/ 6`@b@Kd
publicint getEveryPage(){ F"bz<{
return everyPage; S,j. ?u*!
} f S[-K?K
&s(J:P$!
/** =W &Mt
* @param everyPage qJag>OY
* The everyPage to set. m):*>o55
*/ /Kd7#@
publicvoid setEveryPage(int everyPage){ l n\qvD_
this.everyPage = everyPage; 8IA1@0n&
} /)T~(o|i
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/** }jUsv8`}8R
* @return p#CjkL
* Returns the hasNextPage. z&WtPSyGj
*/ 2E?!Q I\O
publicboolean getHasNextPage(){
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return hasNextPage; @ 5^nrB
} -OSj<m<
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/** 8L,=E ap
* @param hasNextPage %@Z;;5 L
* The hasNextPage to set. FpiTQC7d
*/ b8e\( Dww
publicvoid setHasNextPage(boolean hasNextPage){ u4_QLf@I
this.hasNextPage = hasNextPage; M+0PEf.
} \nt~K}a
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/** {9yf0n
* @return BY.k.]/
* Returns the hasPrePage. e{7\pQK
*/ Bb:C^CHIQm
publicboolean getHasPrePage(){ qa-FLUkIk!
return hasPrePage; r=&,2meo
} qXg&E}]:=
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/** ni&|;"Nt-
* @param hasPrePage #]x3(}3W
* The hasPrePage to set. VJ=>2'I
*/ Km;}xke6
publicvoid setHasPrePage(boolean hasPrePage){ ujRXAN@mC
this.hasPrePage = hasPrePage; +4.s4&f)
} #D4
QXZyiJX}
/** @uH!n~QV
* @return Returns the totalPage. y-db CYMc
* {$,\Qg
*/ t|$jgM
publicint getTotalPage(){ P&uSh?[ ^
return totalPage; cf88Fd6l/
} gLB(A\yG
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/** ? Bpnnwx
* @param totalPage a(|6)w-
* The totalPage to set. oGRk/@
*/ )"S%'myj
publicvoid setTotalPage(int totalPage){ !1G
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this.totalPage = totalPage; 16zRe I(
} PqV
F}
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} $
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0+e=s0s.
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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 v-tI`Qpb
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个PageUtil,负责对Page对象进行构造: .;]WcC<3
java代码: pL"{Uqi
x
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V
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/*Created on 2005-4-14*/ E{<#h9=>
package org.flyware.util.page; t,?,T~#9
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import org.apache.commons.logging.Log; \ZZ6r^99
import org.apache.commons.logging.LogFactory; 5c` ;~
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/** -N*[f9EJB
* @author Joa $6a9<&LP_
* Gr\ ]6
*/ A?H#bRAs
publicclass PageUtil { 1zPS#K/3
8>9Mh!t}(I
privatestaticfinal Log logger = LogFactory.getLog Z)s
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"[N2qJ}p
(PageUtil.class); 2iG+Ek-?"
)X0=z1$
/** MY,~leP&
* Use the origin page to create a new page '4 *0Pw
* @param page <= o<lRU
* @param totalRecords ,c&u\W=p
* @return |9jK-F6
*/ x95s%29RS
publicstatic Page createPage(Page page, int 7|5kak>=
@3.Z>KONx
totalRecords){ uge r:cD
return createPage(page.getEveryPage(), J"C9z{[Z&
9"S2KT @8
page.getCurrentPage(), totalRecords); Rn~'S2`u
} YVMvT>/,
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/** W3,r@mi^s7
* the basic page utils not including exception Ddr.6`VJ
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handler ::>|[ND
* @param everyPage X5iD<Lh
* @param currentPage ~JT`q:l-q
* @param totalRecords ] 0X|_bU
* @return page ?>;aD
*/ G}8tFo.d1
publicstatic Page createPage(int everyPage, int <D.E.^Y
C}h(WOcr`X
currentPage, int totalRecords){ `
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everyPage = getEveryPage(everyPage); z}[u~P,
currentPage = getCurrentPage(currentPage); < o?ua}
int beginIndex = getBeginIndex(everyPage, juR>4SH
9<u&27.
currentPage); h-96 2(LG
int totalPage = getTotalPage(everyPage, >%tP"x{
:^]Po$fl
totalRecords); v 6
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boolean hasNextPage = hasNextPage(currentPage, 9WG=3!-@
,/?J!W@m
totalPage); oJTEN}fL
boolean hasPrePage = hasPrePage(currentPage); $mPR)T
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returnnew Page(hasPrePage, hasNextPage, KR( apO
everyPage, totalPage, PEI$1,z
currentPage, {N2GRF~c-y
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beginIndex); P8YnKyI,.
} LA6XTgcu
p6- //0qb
privatestaticint getEveryPage(int everyPage){ L ci?
return everyPage == 0 ? 10 : everyPage; -dM~3'
} SSI> +A
<.ZIhDiEl
privatestaticint getCurrentPage(int currentPage){ w5i*pOG)Z
return currentPage == 0 ? 1 : currentPage; X"TL'"?fo
} K6->{!8]k
] V/5<O1
privatestaticint getBeginIndex(int everyPage, int q]="ek&_
E:9RskI
currentPage){ &}u_e`A
return(currentPage - 1) * everyPage; w:
BJ4bi=
} ._0$#J S[
D+!T5)>(
privatestaticint getTotalPage(int everyPage, int K}cZK
&>c=/]Lop
totalRecords){ 7**zb"#y
int totalPage = 0; %bP+P(vZ
&b@_ah+f
if(totalRecords % everyPage == 0) K>'4^W5d,
totalPage = totalRecords / everyPage; xQZOGq
else %1{S{FB
totalPage = totalRecords / everyPage + 1 ; .uA
O.<
%`$bQU
return totalPage; >J9Qr#=H2
} E/H9#
@g[ijs\
privatestaticboolean hasPrePage(int currentPage){ Ov(k:"N
return currentPage == 1 ? false : true; hWt_}'
} i|h{<X7[
ikZYc ${
privatestaticboolean hasNextPage(int currentPage, Jj]<SWh
l3u [
int totalPage){ '{,JuX"n
return currentPage == totalPage || totalPage == H2],auBY
dU-:#QV6
0 ? false : true; QHv]7&^rlj
} qg j;E=7
Z%?>H iy'o
^X#)'\T
} :30daKo
e[fld,s
i`i`Hu>
htYfIy{5w
D Z~036
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 (Tq)!h35B
A6KP(@
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 "'DPb%o
@w33u^
做法如下: JXuks`:Q
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 p!E*ANwX
AIP0PJI3
的信息,和一个结果集List: M7qg\1L
java代码: |+h x2?Nv
k6 OO\=
&LV'"2ng8
/*Created on 2005-6-13*/ =n.&N
package com.adt.bo; {U9{*e$=
*=md!^x`
import java.util.List; 7IUJHc[R?
[?6+ r
import org.flyware.util.page.Page; G9S3r3
*[>{9V
/** 0]ai*\,W7~
* @author Joa sfVzVS[
*/ `_&vvJPn@!
publicclass Result { 1&h\\&ic
nVpDjUpN
private Page page; wI7.M
Gt
yTc&C)Jba
private List content; Z2;~{$&M+
FS7D
/** >uJu!+#
* The default constructor 3Q&@l49q
*/ z>W?\[E<2
public Result(){ #Hy9 ;Q
super(); f/
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} .mnkV -m
UnDX .W*2
/** ;qzn_W
* The constructor using fields e9\_H=t+
* YPs9Pqkn
* @param page :S`12*_g"
* @param content 4{,!'NA
*/ 0 Swu]OE
public Result(Page page, List content){ T2?.o.&u
this.page = page; auB+ g'l
this.content = content; (wH+ 0
} ;Gp9
? 0
}w=|"a|,
/** a'q&[08
* @return Returns the content. {h|kx/4{m
*/ CT\rx>[J.6
publicList getContent(){ s4Jy96<
return content; W T @XHwt
} 0#5&*
ZXj*Vu$_4
/** -f'&JwE0=
* @return Returns the page. 0W
1bZPM
*/ ,-n_(U
public Page getPage(){ e[Z-&'
return page; [IyC}lSW^-
} aYtW!+#
K=4|GZ~p}`
/** >YdLB@
* @param content [pt U}
* The content to set. 2L.6!THG
*/ y`z?lmV)xM
public void setContent(List content){ X~*/ ~f
this.content = content; iDCQqj`
}
zGL.+@
oh:.iL}j
/** Nbf>Y
* @param page v/7^v}[<
* The page to set. f DXTedrG/
*/ e ?Jgk$"
publicvoid setPage(Page page){ yJw.z#bB#
this.page = page; sVlQ5M oo(
} #|V)>")
} H ~<.2b
F${}n1D
F)aF.'$-/
R-k~\vCW
*\0h^^|@
2. 编写业务逻辑接口,并实现它(UserManager, x9]vhR/av
A0ZU #"'/
UserManagerImpl) ihct~y-9W
java代码: ?5[$d{ Gjl
nGDY::nUE
&`g^b^i
/*Created on 2005-7-15*/ H-%
B<7
package com.adt.service; WxJaE;`Ige
L 'e|D=y
import net.sf.hibernate.HibernateException; Nah\4-75&
8yswi[
import org.flyware.util.page.Page; hBDmC_\~
Fbw.Y6
import com.adt.bo.Result; 7?y([i\y
fndH]Yp
/** gd0a,_`M
* @author Joa FbCuXS=+`
*/ 02[*b
publicinterface UserManager { TD/ 4lL~(x
Wq25, M'
public Result listUser(Page page)throws ayg^js2,
V>4v6)N
HibernateException; Vc8w[oS
B;<zA' 1
} a 4?c~bs
UD&pL'{s
e[QEOx/-h2
HSACaTVK
4^^=^c
java代码: jU{~3Gn?
94lz?-j
R$2\Xl@qQF
/*Created on 2005-7-15*/
S O`b+B
package com.adt.service.impl; EO/TuKt
,H/BW`rL]#
import java.util.List; u&j_;Y !6
$b) k
import net.sf.hibernate.HibernateException; ] $F%
=s:Z-*vy!
import org.flyware.util.page.Page; V|2[>\Cv
import org.flyware.util.page.PageUtil; 3'55!DE
h\6 t\_^\
import com.adt.bo.Result; 0<Rq
import com.adt.dao.UserDAO; Q^'xVS_.
import com.adt.exception.ObjectNotFoundException; ^ b{~]I
import com.adt.service.UserManager; Jn\>Sz(96
N8*QAekN
/** m&--$sr
* @author Joa qjN*oM,
*/ 0J.]`kR
publicclass UserManagerImpl implements UserManager { |-]'~@~
^HWa owy=
private UserDAO userDAO; >4?735f=x
6"2IV
/** <,t6A?YoMP
* @param userDAO The userDAO to set. o}L\b,])
*/ Vo(bro4ZQi
publicvoid setUserDAO(UserDAO userDAO){ 5QG?*Z~?7
this.userDAO = userDAO; i&L!?6 5-f
} wYd{X 8$
xeRoif\4c
/* (non-Javadoc) SM.KM_%K
* @see com.adt.service.UserManager#listUser L}tP_ *
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(org.flyware.util.page.Page) ?V =#x.9
*/ we33GMxHl`
public Result listUser(Page page)throws Bf$`Hf6
wd2z=^S~
HibernateException, ObjectNotFoundException { B*}:YV
int totalRecords = userDAO.getUserCount(); 2GRv%:rZ
if(totalRecords == 0) U ?6.UtNf
throw new ObjectNotFoundException 'On%p|s)H
K#x|/b'5d
("userNotExist"); b%xG^jUXsX
page = PageUtil.createPage(page, totalRecords); eY`o=xN
List users = userDAO.getUserByPage(page); Hw,@oOh.
returnnew Result(page, users); l-8rCaq&J
} pE{Ecrc3|
B#o6UO\
} $g
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V17!~
Eu[/* t+l
4
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qy/t<2'
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 Wfsd$kN6{
|u#7@&N1
询,接下来编写UserDAO的代码: Z)<lPg!YAR
3. UserDAO 和 UserDAOImpl: &[5pR60
java代码: n"Wlfd0
*~`BG5w
scy_
/*Created on 2005-7-15*/ CWSc #E
package com.adt.dao; +?6@%mW'
5jsZJpk$
import java.util.List; Fzy5k?R
q!YAA\'31
import org.flyware.util.page.Page; Fm[3Btn
wT +\:y
import net.sf.hibernate.HibernateException; rw[Ioyr-
`ix&j8E22w
/** n]jw!;
* @author Joa z2 mjm
*/ `r&]Ydu:
publicinterface UserDAO extends BaseDAO { a[E}o<{
1/J6<FVq
publicList getUserByName(String name)throws j7J'd?l
nPUD6<bF
HibernateException; #cqI0ny?G
I
MG^L
publicint getUserCount()throws HibernateException; /])P{"v$^
D"&Sd@a{
publicList getUserByPage(Page page)throws &BN#"- J
A5Lzd
HibernateException; \%&eDE 0
8"o@$;C
} W@D./Th
'i4L.&
cVDcda|PE
k&17 (Tv$
es<
java代码: XfN(7d0
^95njE`>t`
E[<*Al+N
/*Created on 2005-7-15*/ P+DIo7VTX
package com.adt.dao.impl; bbT$$b-
>+):eBL
import java.util.List; T@a|*.V
Y}
6@ w
import org.flyware.util.page.Page; Zr[B*1,ZV
`Ay:;I
import net.sf.hibernate.HibernateException; -\2hSIXj
import net.sf.hibernate.Query; e(Rbq8D
%a!gN
import com.adt.dao.UserDAO; %Rk DR
:TkMS8
/** S q{@4F}d
* @author Joa J M`[|"R%
*/ c7RQ7\
public class UserDAOImpl extends BaseDAOHibernateImpl iU AY
=Q*3\)7
implements UserDAO { R[@}Lg7+v
X!m
lC51
/* (non-Javadoc) ],Yy)<e.
* @see com.adt.dao.UserDAO#getUserByName lX"6m}~D
P~%+KxwZQ
(java.lang.String) >T-4!ZvS\j
*/ =nqHVRA
publicList getUserByName(String name)throws uaZHM@D
5]n\E?V'L
HibernateException { [v`kqL~
String querySentence = "FROM user in class :aH5=@[!y
gFsqCx<q
com.adt.po.User WHERE user.name=:name"; Eihn%Esa
Query query = getSession().createQuery KD?b|y@
bP> Kx-%q
(querySentence); tS-gaT`T
query.setParameter("name", name); 73Hm:"Eqd
return query.list(); Fu5c_"!
} ,e$6%R
kpxGC,I^*.
/* (non-Javadoc) '.k'*=cq0
* @see com.adt.dao.UserDAO#getUserCount() ^b.#4i(v
*/ 6[SIDOp*^
publicint getUserCount()throws HibernateException { b`@J"E}
int count = 0; 7VL|\^Y `q
String querySentence = "SELECT count(*) FROM na"!"C
s3
T"<)B^8f
user in class com.adt.po.User"; 7Gy:T47T\@
Query query = getSession().createQuery 'u~0rMe4})
@0d"^
(querySentence); MzDosr3:
count = ((Integer)query.iterate().next 5{bc&?"
O8SE)R~
()).intValue(); _
j`tR:
return count; SZ}=~yoD(
} k81%$E
5DVYHN9c|
/* (non-Javadoc) b` va\'&3
* @see com.adt.dao.UserDAO#getUserByPage ~]q>}/&YLo
e['<.Yf+
(org.flyware.util.page.Page) }1W@
*/ [c;#>UQMf
publicList getUserByPage(Page page)throws is~2{:
w
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HibernateException { YV!hlYOBi
String querySentence = "FROM user in class 2;0eW&e
N$x&k$w R
com.adt.po.User"; kw
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Query query = getSession().createQuery Ih>s2nL
)Yv=:+f
(querySentence); |0Xf":
query.setFirstResult(page.getBeginIndex()) AI`k
}sA~
.setMaxResults(page.getEveryPage()); &{UqGD#1&
return query.list(); r$8'1s37`
} P=_fYA3
/KNDo^P
} ;S '?l0
,Aai-AGG@
{M5t)-
*} ?
n,2
至此,一个完整的分页程序完成。前台的只需要调用 =^i K^)
mEsb_3?#+
userManager.listUser(page)即可得到一个Page对象和结果集对象 D:f=Z?L)>
Od)y4nr3~
的综合体,而传入的参数page对象则可以由前台传入,如果用 o+7)cI
-*z7`]5J
webwork,甚至可以直接在配置文件中指定。 Jv+w{"&
Fx|`0LI+C
下面给出一个webwork调用示例: ][
I OlR
java代码: 9@yF7
sRA2O/yKCE
U3Z=X TB
/*Created on 2005-6-17*/ t ^[fu,
package com.adt.action.user; DA.k8M
W\NC3]
import java.util.List; N2"B\
bd~m'cob>
import org.apache.commons.logging.Log; kS8?N`2}LV
import org.apache.commons.logging.LogFactory; 6(rN(C
import org.flyware.util.page.Page; T7^;!;i`X
`Z8k#z'bN
import com.adt.bo.Result; <|jh3Hlp
import com.adt.service.UserService; <r.QS[:h
import com.opensymphony.xwork.Action; pCA`OP);=
/Pkz3(1
/** 0o"aSCq8t
* @author Joa f!`?_
*/ *LU/3H|}
publicclass ListUser implementsAction{ 9$HBKcO
>%om[]0E
privatestaticfinal Log logger = LogFactory.getLog RYjK4xT?Y/
tP7<WGHd/
(ListUser.class); oV0T
d]`6N
private UserService userService; |w}j!}u
CV.|~K0O
private Page page; @$ Zh^+x!
Q_|}~4_+
privateList users; 5P%#5Yr2
ds9'k.
/* ypx~WXFK
* (non-Javadoc) 6]Hwr_/tk
* 45sEhs[$
* @see com.opensymphony.xwork.Action#execute() CqlxE/|
*/ Y?NL|cW4
publicString execute()throwsException{ 9hfg/3t('
Result result = userService.listUser(page); "TZY)\{L
page = result.getPage(); {pIh/0
users = result.getContent(); $t.oGd@N
return SUCCESS; LhbdvJAk@
} Hf?@<4
%m\:AK[}
/** mn?F;=qE
* @return Returns the page. 3ai[ r
*/ `\62 iUN
public Page getPage(){ qBX_v5pvVA
return page; '-YiV
} B_Q{B|eEt&
)|xu5.F
/** L
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* @return Returns the users. KtL?,zi
*/ E6TeZ%g
publicList getUsers(){ 5 ix*wu`,
return users; !q\=e@j-i
} S
F*C'
<v|"eq}
/** ,bl }@0A
* @param page ]yf?i350
* The page to set. kk-<+R2
*/ RTcxZ/\"#
publicvoid setPage(Page page){ dDpAS#'s\
this.page = page; (4cdkL
} .Rk8qRB
LBCH7@V1yR
/** >nghFm
* @param users S@HC$
* The users to set. uI7n{4W*x
*/ w~b:9_reY
publicvoid setUsers(List users){ $:F+Nf
8
this.users = users; OX]$Xdb2:
} _M%S
~4{q
/** "kyCY9)%
* @param userService wS*r<zj
* The userService to set. #XDgvX >
*/ =#V^t$
publicvoid setUserService(UserService userService){ &<BBPn@\
this.userService = userService; pY"WW0p"C
} ls^Z"9P
} = UH3.
<#C,66k
][$I~nRf
lLTqk\8g
z!"vez
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, 4|`>}Nu
#uhUZq
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 ?7aZU
DO*U7V02
么只需要: sE% $]Jp
java代码: Z
v@nK%#J
o%t4WQ|bj
5CFNBb%Xy
<?xml version="1.0"?> Qu61$!
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork nnv|GnQST
q*3OWr
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ?uq`| 1`
|:1{B1sqA
1.0.dtd"> .xsfq*3e5
N; g@lyo
<xwork> ^?VQ$o2
<=*f
<package name="user" extends="webwork- Gaix6@X6'
4b2d(x)0X
interceptors"> k XSX<b <%
c
C3>Ff'
<!-- The default interceptor stack name l*1|B3#m!
e3p|g]
--> |"gL{De
<default-interceptor-ref y@3p5o9lv-
t%lat./yT
name="myDefaultWebStack"/> rm[C{Pn
>$4#G)s
<action name="listUser" $d?W1D<A
G\@pg;0|y
class="com.adt.action.user.ListUser"> ljKIxSvCFp
<param +X=*>^G(-
Y,}_LS$f
name="page.everyPage">10</param> Jl/w P
<result WoEK #,I;
nq M7Is
name="success">/user/user_list.jsp</result> p~$cwbQ!
</action> O(T5
$H)^o!
</package> 4@PA+(kvS
Xqf,_I=V
</xwork> |THpkfW
%2}fW\%'
5RP kAC
[8iY0m_Qe
$'J3
/C7
jc5[r;#
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 "?8)}"/f
|?!i},Ki;
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 &W2*'$j"_
3z8i0
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 U)J5K
'$9o(m#
N''QQBUD
yKc-:IBb{u
u R0UfKK
我写的一个用于分页的类,用了泛型了,hoho b[74$W{
`z|0O
java代码: C~ 1]
1R2IlUlzFr
&9yZfp
package com.intokr.util; \2\{c1df
>+2&7u
import java.util.List; 9kL,69d2
bv+u7B6,
/** ){;XI2
* 用于分页的类<br> b,xZY1a
* 可以用于传递查询的结果也可以用于传送查询的参数<br> Xh9QfT ,
* zPby+BP
* @version 0.01 n:5M
E*
* @author cheng 4zoQe>v~
*/ '2(m%X\6
public class Paginator<E> { HlGSt$woX
privateint count = 0; // 总记录数 +,76|oMsQ%
privateint p = 1; // 页编号 `b?uQ\#-M
privateint num = 20; // 每页的记录数 4b;Mb
privateList<E> results = null; // 结果 =oBpS=<7
KdVKvs[
/** l=~!'1@L}
* 结果总数 2JfSi2T
*/ n7Ao.b%uk-
publicint getCount(){ SMN.AJ
J
return count; KgL!~J
} q/i2o[f'n
b($hp%+yJ
publicvoid setCount(int count){ |+#Zuq
this.count = count; I?e5h@uE
} xRh 22z
(S[z
/** d][
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* 本结果所在的页码,从1开始 oZ'a}kF
* N^L@MR-
* @return Returns the pageNo. 8x{Owj:Q
*/ .biq)Le
publicint getP(){ Kj4/fB
return p; ]VI^ hhf
} ATs_d_Sz
K`4lL5oH
/** {r^_ g(.q
* if(p<=0) p=1 :Jd7q.
* 1!#N-^qk
* @param p `Q@7,z=f
*/ M(-)\~9T
publicvoid setP(int p){ RTOA'|[0M
if(p <= 0) fLDrit4_Q
p = 1; oTw!#Re)
this.p = p; F? #3
} DHO]RRGV
mQ[$U
/** <FT7QO$I
* 每页记录数量 yJA~4
*/ +}:Z9AAMy
publicint getNum(){ :/5m
D
return num; sZ `Tv[
} AxEyXT( h5
&G{GLP?H
/** &o:5lxR{
* if(num<1) num=1 T+Oqd\05.+
*/ d ^bSV4
publicvoid setNum(int num){ HbTVuf o
if(num < 1) fM=o?w6v
num = 1; MxE]EJZ
this.num = num; `|t,Uc|7!
} k&Pt\- 9on
S=@+qcI
/** }k^uup*{
* 获得总页数 p Cz6[*kC
*/ ]J7qsMw
publicint getPageNum(){ pBsb>wvej
return(count - 1) / num + 1; dY1t3@E
} :qzg?\(
VPMu)1={:p
/** q<YM,%mgj
* 获得本页的开始编号,为 (p-1)*num+1 B%F]K<
*/ L}Z.FqJ
publicint getStart(){ *$Q>Om]
return(p - 1) * num + 1; iq&3S 0
} ipSMmpB
wuqe{?
/** (NJ{>@&
* @return Returns the results. LlTD =tJ0
*/ bWe2z~dP
publicList<E> getResults(){ w\buQ6pR)
return results; (.J/Ql0Y
} MO`Y&<g~A
T.bFB+'E|
public void setResults(List<E> results){ !:(+#
this.results = results; qGinlE&\
} ~D52b1f
}M07-qIX{
public String toString(){ d4Uw+3ikW
StringBuilder buff = new StringBuilder OSu&vFKz
rj4@
(); <8r"QJY/
buff.append("{"); 8Pn
buff.append("count:").append(count); +B? qx
Q
buff.append(",p:").append(p); g"-j/ c
buff.append(",nump:").append(num); =EJ&=t
buff.append(",results:").append ]7HR
U6$
s:T%,xS
(results); (,Y[2_Zv
buff.append("}"); -&/?&{Q0
return buff.toString(); 85<k'>~L
} "x,lL
8ro`lX*F@2
} JE.$]){
~
#jQFyOh
H%_^Gy8f