Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 b,RQ" {
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 nTPq|=C
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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 5+iXOs<
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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 ;XGO@*V5T
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分页支持类: XXPpj< c
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java代码: 4#wZ#}
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package com.javaeye.common.util; hxuc4C\J
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import java.util.List; &qae+p?
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publicclass PaginationSupport { .L}k-8
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publicfinalstaticint PAGESIZE = 30; #qdfr3
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privateint pageSize = PAGESIZE; j
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privateList items; {3*Zx"e![
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privateint totalCount; @
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privateint[] indexes = newint[0]; di]TS9&9
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privateint startIndex = 0; #w#:f
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public PaginationSupport(List items, int p;9"0rj,z
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totalCount){ NN@'79x
setPageSize(PAGESIZE); h7F5-~SpD
setTotalCount(totalCount); K0]42K
setItems(items); Q}:#Hz?U
setStartIndex(0); #>dj!33
} =^`?O* /;
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public PaginationSupport(List items, int xh9Os <
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totalCount, int startIndex){ ])NQzgS
setPageSize(PAGESIZE); aLt2fB1 )
setTotalCount(totalCount); 4
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setItems(items); MI\35~JAN
setStartIndex(startIndex); {#4F}@Q
} fy|$A@f
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public PaginationSupport(List items, int &-hXk!A
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totalCount, int pageSize, int startIndex){ yw+LT,AQ.
setPageSize(pageSize); )>U7+ Me
setTotalCount(totalCount); MC;2.e`
setItems(items); h@yn0CU3.
setStartIndex(startIndex); k?;B1D8-n
} j NkobJ1
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publicList getItems(){ gis;)al
return items; GX;~K
} ^n&_JQIXb
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publicvoid setItems(List items){ 5l4YYwd>v
this.items = items; jPa"|9A
} V3<H8pL
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publicint getPageSize(){ r: M>/Z/
return pageSize; 2nkymEPu
}
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publicvoid setPageSize(int pageSize){ ,v$Q:n|
this.pageSize = pageSize; r6gfxW5
} &ws^Dm]R
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publicint getTotalCount(){ dh
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return totalCount; xY>@GSO1
} rc`}QoB)R
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publicvoid setTotalCount(int totalCount){ z~(3S8$
if(totalCount > 0){ H?_>wQj&
this.totalCount = totalCount; sFV&e->AN\
int count = totalCount / xTg=oq
N`et]'_A}
pageSize; ce:p*
if(totalCount % pageSize > 0) ;{89 *e*)
count++; F_F02:t
indexes = newint[count]; !8*lU2
for(int i = 0; i < count; i++){ ]I'dnd3e
indexes = pageSize * O QGKH6q
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i; 85?;\5%-
} i8->3uB
}else{ ,9Si3vn
this.totalCount = 0; D1R$s*{
} u N8RG_Mb
} W.CbNou
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publicint[] getIndexes(){ 7!U^?0?/
return indexes; `i<omZ[aT
} @|([b r|O
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publicvoid setIndexes(int[] indexes){ WT63ve
this.indexes = indexes; a(uZ}yS$
} 5yk#(i7C
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publicint getStartIndex(){ 5y8VA4L/o
return startIndex; c*.-mS~Z`
} D9h
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publicvoid setStartIndex(int startIndex){ G&
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if(totalCount <= 0) je85G`{DC
this.startIndex = 0;
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elseif(startIndex >= totalCount) 5Ky(C6E$s
this.startIndex = indexes * o{7 a$V
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[indexes.length - 1]; e2^TQv2(=e
elseif(startIndex < 0) % 'OY
this.startIndex = 0; _Wqy,L;J
else{ %2y5a`b
this.startIndex = indexes KX
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[startIndex / pageSize]; gCq'#G\Z
} T>68 ,; p
} ,&.$r/x|?
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publicint getNextIndex(){ C),i#v
int nextIndex = getStartIndex() + Z+=M_{`{
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pageSize; YD;G+"n?T
if(nextIndex >= totalCount) sGa}Cf;H@g
return getStartIndex(); Ad&VOh+0
else $[UUf}7L
return nextIndex; wJj:hA}
} LXqPNVp#
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publicint getPreviousIndex(){ Cxeam"-HTt
int previousIndex = getStartIndex() - H*e +
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pageSize; &`oybm-p(
if(previousIndex < 0) TV=K3F5)M
return0; McpQ7\*h
else ocu,qL)W
return previousIndex; m?kyAW'|
} [ ou$*
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} iX[g
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抽象业务类 1ktxG1"1
java代码: $<AaeyR!N
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/** e3ce?gk
* Created on 2005-7-12 Lw2VdFi>E&
*/ rr,w/[
package com.javaeye.common.business; \<ysJgqUG
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import java.io.Serializable; gB~^dv {
import java.util.List; ?~b(iZ
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import org.hibernate.Criteria; -We9
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import org.hibernate.HibernateException; HItNd
import org.hibernate.Session; f7y.##W G
import org.hibernate.criterion.DetachedCriteria; v2_` iwE
import org.hibernate.criterion.Projections; J#t-."f6^
import 6tFi\,)E
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org.springframework.orm.hibernate3.HibernateCallback; ^qnmKA>"F
import m7DKC,
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org.springframework.orm.hibernate3.support.HibernateDaoS ES?*w@x
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upport; `XpQR=IOMb
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import com.javaeye.common.util.PaginationSupport; k/D{&(F ~
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public abstract class AbstractManager extends 4Y$\QZO
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HibernateDaoSupport { 7f4O~4.[i
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privateboolean cacheQueries = false; &7oL2Wf
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privateString queryCacheRegion; - Z`RKR8C
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publicvoid setCacheQueries(boolean vENf3;o0
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cacheQueries){ ZXGi> E
this.cacheQueries = cacheQueries; QW$p{ zo
} r*]pL<
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publicvoid setQueryCacheRegion(String ~`C_B]3|
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queryCacheRegion){ 'It8h$^j
this.queryCacheRegion = @0 /qP<E
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queryCacheRegion; fum.G{}
} P.qzP/Ny
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publicvoid save(finalObject entity){ ]jFl?LA%7
getHibernateTemplate().save(entity); H#DvCw
} 8'HS$J;C
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publicvoid persist(finalObject entity){ q;")
getHibernateTemplate().save(entity); uINdeq 7|F
} C!a1.&HHZ7
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publicvoid update(finalObject entity){ ".tL+A[
getHibernateTemplate().update(entity); -^lc-$0
} @(~:JP?KNC
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publicvoid delete(finalObject entity){ s0^(yEcq
getHibernateTemplate().delete(entity); \?d3Pn5`
} 4a"Fu<q
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publicObject load(finalClass entity, AoeRoqg
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finalSerializable id){ X
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return getHibernateTemplate().load 6FQi=}O 1
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(entity, id); s:Ml\['x
} +7^p d9F.
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publicObject get(finalClass entity, 1(Ta*"(0Ip
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finalSerializable id){ $KO2+^%y
return getHibernateTemplate().get LWN{
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(entity, id); B-R#?Xn:!I
} :Ko6.|
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publicList findAll(finalClass entity){ ^k;]"NR
return getHibernateTemplate().find("from LmePJ
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" + entity.getName()); S@FO&o 0
} o)/Pr7Qn
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publicList findByNamedQuery(finalString !qj[$x-ns
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namedQuery){ ds(?:zx#
return getHibernateTemplate ]~KLdgru_
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().findByNamedQuery(namedQuery); vRmn61
} jdP)y]c
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publicList findByNamedQuery(finalString query, t>I.1AS
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finalObject parameter){ G
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return getHibernateTemplate t?W}=%M[
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().findByNamedQuery(query, parameter); X#lNS+&='
} 'J|)4OG:
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publicList findByNamedQuery(finalString query, _1p8(n
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finalObject[] parameters){ l%0bF9\
return getHibernateTemplate U]iI8c
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().findByNamedQuery(query, parameters); f'^uuO#x
} d,b4q&^X8
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publicList find(finalString query){ `hi=y BO
return getHibernateTemplate().find //q(v,D%Q
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(query); &12KpEyf
} -3EQRqVg
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publicList find(finalString query, finalObject (+>
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parameter){ QPJ\Iu@D$
return getHibernateTemplate().find d(T4Kd$r
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(query, parameter); .$qa?$@
} G<;~nAo?f0
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public PaginationSupport findPageByCriteria <v:VA!]
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(final DetachedCriteria detachedCriteria){ tnRf!A;m
return findPageByCriteria oJz2-PmX
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 3!"N;Q"
} )/H;5 cn
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public PaginationSupport findPageByCriteria Km`
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(final DetachedCriteria detachedCriteria, finalint sgX!4wG&Z
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startIndex){ I0Pw~Jj{
return findPageByCriteria lkn|>U[
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(detachedCriteria, PaginationSupport.PAGESIZE, 2$JGhgDI
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startIndex); !eLj +0
} ti\
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public PaginationSupport findPageByCriteria {PHH1dC{
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(final DetachedCriteria detachedCriteria, finalint y_Y(Xx3
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pageSize, &L;ocd$
finalint startIndex){ BUO5g8m{
return(PaginationSupport) "O&93#8
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getHibernateTemplate().execute(new HibernateCallback(){ U0~_'&Fe
publicObject doInHibernate ?+yr7_f3*
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(Session session)throws HibernateException { _R4}\3}!
Criteria criteria = 9%!h/m>rW
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detachedCriteria.getExecutableCriteria(session); c/;;zc
int totalCount = ZZw`8 E
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((Integer) criteria.setProjection(Projections.rowCount RZOK+!H:
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()).uniqueResult()).intValue(); Jh26!%<Bl
criteria.setProjection ejROJXB
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(null); QQ*sjK.(
List items = J1?;'
2"Os9 KD
criteria.setFirstResult(startIndex).setMaxResults ~ZHjP_5Q
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(pageSize).list(); [2%[~&4
PaginationSupport ps = vl"w,@V7
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new PaginationSupport(items, totalCount, pageSize, K$CC ~,D
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startIndex); F^i3e31*t
return ps; Wv;0PhF
} ]ss[n.T0*
}, true); zA,vp^
} Z*,e<zNQ
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public List findAllByCriteria(final D -}>28
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DetachedCriteria detachedCriteria){ `c`VIq?
return(List) getHibernateTemplate 0Y.z
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().execute(new HibernateCallback(){ 7+O)AU{
publicObject doInHibernate @CMI$}!{V
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(Session session)throws HibernateException { kB7vc>@1
Criteria criteria = !NXjax\r
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detachedCriteria.getExecutableCriteria(session); wj)LOA0
return criteria.list(); vB:\ZX4
} Y"Cf84E
}, true); @=-(H<0
} P"YdB|I
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public int getCountByCriteria(final _:x]'w%
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DetachedCriteria detachedCriteria){ E
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Integer count = (Integer) Ss3p6%V/
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getHibernateTemplate().execute(new HibernateCallback(){ :6n#y-9^1
publicObject doInHibernate o+A7hBM^
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(Session session)throws HibernateException { B}e/MlX3M
Criteria criteria = nzq
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detachedCriteria.getExecutableCriteria(session); L*@`i ]jl
return 3Cf9'C
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criteria.setProjection(Projections.rowCount Ayz*2N`%
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()).uniqueResult(); u[>"_!T
} wi(Y=?=
}, true); y Zafq"o
return count.intValue(); &Mh.PzO=b
} L^J4wYFTO
} ?=u?u
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用户在web层构造查询条件detachedCriteria,和可选的 [FFr}\}bY
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 M4^G3c<
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PaginationSupport的实例ps。 ?
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ps.getItems()得到已分页好的结果集 _N DQ2O
ps.getIndexes()得到分页索引的数组 uP~,]ci7
ps.getTotalCount()得到总结果数 <Ap_#
ps.getStartIndex()当前分页索引 X! d-"[
ps.getNextIndex()下一页索引 Gh;\"Qx
ps.getPreviousIndex()上一页索引 mdi!Q1pS
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ``MO5${
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 3efOgP=L
ah>c)1DA*H
一下代码重构了。 E`HoJhB
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我把原本我的做法也提供出来供大家讨论吧: i~@gI5[k+
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首先,为了实现分页查询,我封装了一个Page类: }:m#}s
java代码: l6M?[
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/*Created on 2005-4-14*/ <)qa{,GX\
package org.flyware.util.page; <=(K'eqC^
7 N}@zPAZ
/** 7Cz~nin>7
* @author Joa HqGI.
* ysaRH3M
*/ r~b.tpH
publicclass Page { a>4/2#J
6pt,]FlU
/** imply if the page has previous page */ qe]D4K8`Q3
privateboolean hasPrePage; I?T
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/** imply if the page has next page */ NdK`-RT
privateboolean hasNextPage; V@'Xj .ze
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/** the number of every page */ xP8/1wd.
privateint everyPage; -l[H]BAMXy
O,$*`RZpx
/** the total page number */ fB2ILRc
privateint totalPage; X5WA-s(?0
CD1Ma8I8
/** the number of current page */ R|?n
privateint currentPage; B`SX3,3
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/** the begin index of the records by the current x[A|@\Z
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query */ l)r\SE1
privateint beginIndex; .Xlo-gHk
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/** The default constructor */ [* xdILj
public Page(){ uQ=u@qtp
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} FPc`J
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/** construct the page by everyPage Q%CrB>|@
* @param everyPage ^B"LT>.[
* */ }T_"Vg q
public Page(int everyPage){ W ?x~"-*
this.everyPage = everyPage; fh#:j[R4e
} yQJ0",w3o.
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/** The whole constructor */ 8)>>EN8 R
public Page(boolean hasPrePage, boolean hasNextPage, GcM1*)$ 4
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int everyPage, int totalPage, lDS y$
int currentPage, int beginIndex){ "rdpA[>L
this.hasPrePage = hasPrePage; FM]clC;X?
this.hasNextPage = hasNextPage; +|C@B`h
this.everyPage = everyPage; :6n4i$
this.totalPage = totalPage; 3MQHoxX
this.currentPage = currentPage; WUS%4LL(
this.beginIndex = beginIndex; _'p/8K5)=
} =CzGI|pb
:k9T`Aa]
/** |AvPg
* @return .7.G}z1
* Returns the beginIndex. k$=L&id
*/ le:}MM
publicint getBeginIndex(){ R3g)LnN
return beginIndex; >VhZv75
} @tT`s^e
O%%Q./oh
/** $uLTYu
* @param beginIndex @5d^ C
* The beginIndex to set. <*vR_?!
*/ F`KXG$
publicvoid setBeginIndex(int beginIndex){ KKwM\
this.beginIndex = beginIndex; VjM/'V5
} JCH9~n.
UV(`.
/** NG3?OAQTw
* @return q,K|1+jn
* Returns the currentPage. G
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*/ wn"\@Qv G
publicint getCurrentPage(){ SY9 5s
return currentPage; "]3o933D
} we}xGb.u
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/** A":=-$)
* @param currentPage ^aqQw u
* The currentPage to set. l#uF%;GDX
*/ "s@Hg1
publicvoid setCurrentPage(int currentPage){ "=2\kZ
this.currentPage = currentPage; 27}:f?2hbJ
} ?* ~4~ZEE
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w
/** y/@Bhzc
* @return &q&z$Gc;m
* Returns the everyPage. f (C:J[;Z
*/ @l3&vt2=J
publicint getEveryPage(){ :TVo2Zm[@
return everyPage; +:Xg7H*
} FM%WMyb[
UhR^Y{W5
/** "IS; o o$g
* @param everyPage ,3rsjoKhd
* The everyPage to set. #@nPB.
*/ !" FEp
publicvoid setEveryPage(int everyPage){ H/t0#
this.everyPage = everyPage; \[!{tbK`2
} >0 7i"a
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/** 2V8"jc
* @return e O~p"d-|
* Returns the hasNextPage. Ju5Dd\
*/ EFiVwH
publicboolean getHasNextPage(){ $Ptl&0MN%
return hasNextPage; {pQ8/Af!
} /.s
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UV|{za$&/
/** W +Piqf*
* @param hasNextPage 6r^ZMW
* The hasNextPage to set. o>*`wv
*/ FoE}j
publicvoid setHasNextPage(boolean hasNextPage){ %cs"PS
this.hasNextPage = hasNextPage; J3+qnT8X
} ,1~B7Zd
((?"2 }1r
/** TlO=dLR7d
* @return LQqba4$
* Returns the hasPrePage. !C4)P3k
*/ .WeSU0XG
publicboolean getHasPrePage(){ Q@p'nE,
return hasPrePage; p v4#`.m
} 7E*0;sA#
"z6p=B"?3
/** D=LsoASVI
* @param hasPrePage Ww~C[8q
* The hasPrePage to set. +dCR$<e9r
*/ n=f?Q=h\3
publicvoid setHasPrePage(boolean hasPrePage){ "4KyJ;RA*
this.hasPrePage = hasPrePage; Na]ITCVR
} Tb^1#O
?AO=)XV2
/** zgS)j9q}
* @return Returns the totalPage. ys)
* X'.lh#&
*/ qi^kf
publicint getTotalPage(){ 3f>9tUWhTy
return totalPage; 8bw,dBN
} zn'Mi:O'p
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/** {OQ)Np!
* @param totalPage uR=*q a
* The totalPage to set. N f?\O@
*/ 2/ )~$0
publicvoid setTotalPage(int totalPage){ {y|.y~vW
this.totalPage = totalPage; f% 8n?f3;u
} Dd
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} 3Zz_wr6
sw$JY}Q8x
MB5V$toC
>!PM5%G
bTx4}>=5l
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 A\"4[PXpQ
XYV`[,^h&
个PageUtil,负责对Page对象进行构造: $v8T%'p+
java代码: 8z-wdO\
D41.$t[
}WR@%)7ay
/*Created on 2005-4-14*/ NUBzc'qb
package org.flyware.util.page; zzC{I@b
/^i_tLgb
import org.apache.commons.logging.Log; C9Cl$yZ
import org.apache.commons.logging.LogFactory; >0 := <RW
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/** Nog{w
* @author Joa JBV
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*
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*/ C:!&g~{cKi
publicclass PageUtil { fX
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privatestaticfinal Log logger = LogFactory.getLog QVb{+`.7
BL0xSNE**
(PageUtil.class); kT^`j^Jr
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/** H_iQR9Ak7
* Use the origin page to create a new page ?U:c\TA,m
* @param page @q|c|X:I
* @param totalRecords gsIp y
* @return Rs'mk6+
*/ vN6)Szim
publicstatic Page createPage(Page page, int (^ J2(
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totalRecords){ KrTlzbw&p\
return createPage(page.getEveryPage(), .%\R L/
$ -]9/Ct
page.getCurrentPage(), totalRecords); u\K`TWb%
} lo7>$`Q
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/** k
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* the basic page utils not including exception sEa| 2$
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handler yTWicW7i
* @param everyPage
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* @param currentPage _bCIVf`
* @param totalRecords ) C#>@W
* @return page UJ)(Sw
*/ p13y`sU=
publicstatic Page createPage(int everyPage, int ^Y"|2 :
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currentPage, int totalRecords){ I_`$$-|
everyPage = getEveryPage(everyPage); 2N&S__
currentPage = getCurrentPage(currentPage); )uCa]IR
int beginIndex = getBeginIndex(everyPage, /7R0w
9 b&HqkXX
currentPage); PmUq~YZ7
int totalPage = getTotalPage(everyPage, e=i9l
dY?>:ce
totalRecords); ()_^:WQO?
boolean hasNextPage = hasNextPage(currentPage, xn<x/e
w\>@>*E>
totalPage); Gbb*p+(
boolean hasPrePage = hasPrePage(currentPage); wemhP8!gc
dsZ-|C
returnnew Page(hasPrePage, hasNextPage, KctbNMU]k
everyPage, totalPage, 2 o5u02x
currentPage, z7JhS|
xc?=fv
beginIndex); `!
)^g/>0i
} _y9NDLRs8
JPe<qf-
privatestaticint getEveryPage(int everyPage){ ,/-DAo~O
return everyPage == 0 ? 10 : everyPage; Zu ![v0
} I5E4mv0<i
E`q)vk
privatestaticint getCurrentPage(int currentPage){ 8J0#lu
return currentPage == 0 ? 1 : currentPage; &*qAB)**
} gGbJk&E
pq,8z= Uf
privatestaticint getBeginIndex(int everyPage, int #@cEJV;5"
zE=^}K+
currentPage){ h(FFG%H(
return(currentPage - 1) * everyPage; Z"9D1Uk
} Oz5Ze/HBN
YZc{\~d
privatestaticint getTotalPage(int everyPage, int 1{CVd m<9
nhB.>ReAi
totalRecords){ TdrRg''@
int totalPage = 0; m>^#:JK
$*+`;PG-
if(totalRecords % everyPage == 0) ?fvK<0S`
totalPage = totalRecords / everyPage; 810uxw{\
else Nf9$q| %!
totalPage = totalRecords / everyPage + 1 ; %xwtG:IKEV
zRA,Yi4;+
return totalPage; ugQySg>
} KD8,a+GL
z#srgyLt
privatestaticboolean hasPrePage(int currentPage){ 4^K<RSYs
return currentPage == 1 ? false : true; l\&Tw[O
} . L]!*
L@~0`z:>iP
privatestaticboolean hasNextPage(int currentPage, #D Oui]
m$^v/pLkM
int totalPage){ ,z|g b]\
return currentPage == totalPage || totalPage == ,Y27uey{wa
joJQ?lG
0 ? false : true; =R||c
} }b]z+4Ua(
X8
xY`$j'u
} 0'II6,:
hWiBLip,z
\aGTi
pB
fTV3lyk
T@on
ue7
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。 'n7Ld6%1
7HEUmKb"
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 Kw&t\},8@
{ VFr8F0*H
做法如下: |BE`ASW;
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 >?^_JEC6
Qr]`flQ8
的信息,和一个结果集List: =.6JvX<d1*
java代码: , n47.S
cy( WD#^
Y~-P9
/*Created on 2005-6-13*/ ck#MpQ!An
package com.adt.bo; uzaDK
h$a%PaVf
import java.util.List; !^(?C@TQ
S0p[Kt
import org.flyware.util.page.Page; oz/Nx{bg
q,2 +\i
/** eGlPi|
* @author Joa dW"=/UW
*/ 3W"l}.&ZJ"
publicclass Result { 6e At`L[K.
]"-c?%L
private Page page; MI|anM
S2"H E`
private List content; vUgMfy&
yq\p%z$:
/** |eFce/
* The default constructor 0I"r*;9?K
*/ Cc>+OUL
public Result(){ 4xzoA'Mb@
super(); &265
B_'D
} N Uo
SR*KZ1U
/** U|)CZcM
* The constructor using fields _Rm1-,3
* GGkU$qp2~
* @param page '(yjq<
* @param content 05/'qf7P,U
*/ E@92hB4D"
public Result(Page page, List content){ z3Q#Wmv2
this.page = page; Gq9pJ
this.content = content; I?Ct@yxhF'
} b=Oec%Adx
}ujl2uhM
/** /}#@uC
* @return Returns the content. -)$5[jM]
*/ )~H&YINhn
publicList getContent(){ #Bi8>S
return content; B0"55g*c
} ad,pHJ`
0XUWK@)P
/** y6N }R
* @return Returns the page. hSF4-Vvb
*/ _!Ir|j.A
public Page getPage(){ ;A;FR3=)
return page; "vN~7%
} !ui:0_
<5:`tC2
/** Z<@dM2b)
* @param content /{*0
\`;
* The content to set. Eao^/MKx-
*/ 9 Aq\1QC
public void setContent(List content){ !OL[1_-4|K
this.content = content; 1CpIK$/
} kNrN72qg
s>1Wjz2M
/** IH$ZPux
* @param page qB8R4wCf
* The page to set. dE]yb|Ld
*/
k;xIo(:
publicvoid setPage(Page page){ XX[CTh?O%
this.page = page; s2t9+ZA+s
} Uy5G,!
} :~%{
m9 D'yXZ
]c~W$h+F
,AEaW
Auk#pO#
2. 编写业务逻辑接口,并实现它(UserManager, d@e2+3<
5!*@gn
UserManagerImpl) Z[?zaQ$
java代码: 1&#qq*{
$Z[W}7{pt#
)H|cri~D
/*Created on 2005-7-15*/ c-q=Ct
package com.adt.service; FoB^iA6e
gvu1
import net.sf.hibernate.HibernateException; l[u=_uaYl
_fE$KaP
import org.flyware.util.page.Page; $,
@,(M`i}
zyPc<\HoK
import com.adt.bo.Result; $fFh4O4
gjDxgNpa
/** 9L9qLF5 t
* @author Joa g8L{xwx<
*/ 1%`Nu ]D
publicinterface UserManager { G%5ZG$as
SKeX~uLz
public Result listUser(Page page)throws w$4*/D}Y
{dXmSuO
HibernateException; }(/\vTn*1
c4Wl^E8
} ?{rpzrc!*
cbaa*qoU
$i]G'fj
ViYfK7Z
Vh'H =J
java代码: SBh"^q
U2vM|7]VP
jHQnD]Hr
/*Created on 2005-7-15*/ j`:D BO&)\
package com.adt.service.impl; P]%)c6Uh
%=`wN^3t2
import java.util.List; J1g+H2
Eu|O<9U\
import net.sf.hibernate.HibernateException; S:8 WBY] M
+sFpIiJg
import org.flyware.util.page.Page; =>htX(k}
import org.flyware.util.page.PageUtil; x".!&5
!yo@i_1D
import com.adt.bo.Result; .)Zs:50l
import com.adt.dao.UserDAO; %_%BbQf
import com.adt.exception.ObjectNotFoundException; E(g$f.9
import com.adt.service.UserManager; FL E3LH
L6Io u
/** $(+#$F<eo+
* @author Joa V[2}
*/ 4=qZ Z>[t
publicclass UserManagerImpl implements UserManager { /X;/}fk
bZW dd6
private UserDAO userDAO; |qz&d=>
{@ Z=b5/P
/** oe<DP7e
* @param userDAO The userDAO to set. 8e32NJ^k~
*/ X+kgx!u'y
publicvoid setUserDAO(UserDAO userDAO){ 2Og<e|
this.userDAO = userDAO; ,#U[)}im
} W^YaC
(I
RmRPR<vGW
/* (non-Javadoc) $0XR<D
* @see com.adt.service.UserManager#listUser wDDNB1_E
NOFuX9/'w
(org.flyware.util.page.Page) apZPHau6h
*/ }inV)QQ
public Result listUser(Page page)throws =z[$o9
%U6A"?To
HibernateException, ObjectNotFoundException { DIw9ov>k
int totalRecords = userDAO.getUserCount(); \![ p-mW{
if(totalRecords == 0) Q?>DbT6
throw new ObjectNotFoundException 7#(0GZN9h%
se=;vp]3a
("userNotExist"); X m3r)Bm'3
page = PageUtil.createPage(page, totalRecords); 4 (XV)QR
List users = userDAO.getUserByPage(page); qL4s@<|~
returnnew Result(page, users); Z rv:uEl
} o 3JSh=
"h-ZwL
} _p^$.\k"
pp@O6
'<{Jlz(u9
yw1-4*$c
D)tL}X$
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 8]D0)
P^AI*tH"m
询,接下来编写UserDAO的代码: 0<93i
3. UserDAO 和 UserDAOImpl: -9Dr;2\
java代码: :!Nx'F9a
#>6Jsnv1
X0Wx\xDg[
/*Created on 2005-7-15*/ +ZOKfX
package com.adt.dao; dhjX[7Bl9
SY.ZEJcv
import java.util.List; <nTZs`$LwL
zx5#eMD
import org.flyware.util.page.Page; WPAT\Al&AE
\/64Xv3L0
import net.sf.hibernate.HibernateException; td7Of(k'
&0i$Y\g
/** }U '
* @author Joa mLx=Zes:.
*/ bYO['ORr@
publicinterface UserDAO extends BaseDAO { !jvl"+_FV
n?U^vK_
publicList getUserByName(String name)throws (&Rql7](8
7>=
HibernateException; 0SQrz$y
pHXs+Ysw+
publicint getUserCount()throws HibernateException; C]Y%dQh+a
yi:}UlO
publicList getUserByPage(Page page)throws Fv*Et-8tN5
[(eX\kL
HibernateException; (%OZ `?`
'E&tEbY
} AGm=0Om
*?\u5O(
UVXSW*$
4jSYR#Hqp`
W*%(J$E
java代码: ]&N>F8.L+
TB-dV'w
XhA tf@n
/*Created on 2005-7-15*/ I{h KN V
package com.adt.dao.impl; 0'
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,,!P-kK$
import java.util.List; |]9L#
zk"8mTg
import org.flyware.util.page.Page; iCLH
TW|- 0
import net.sf.hibernate.HibernateException; vZW[y5
import net.sf.hibernate.Query; 8+J>jZ
r6kJV4I=re
import com.adt.dao.UserDAO; 684d&\(s
>JAWcT)d
/** &_u.q/~
* @author Joa a#k7 aOT0
*/ c&I
public class UserDAOImpl extends BaseDAOHibernateImpl e`:^7$
jijwHL
implements UserDAO { YWs?2I
:Nv7Wt!
/* (non-Javadoc) `a!9_%|8
* @see com.adt.dao.UserDAO#getUserByName Rj4C-X4=
vQ]d?Tp
(java.lang.String) ([
-i5
*/ U1HG{u,"y
publicList getUserByName(String name)throws D6H?*4f]
$8xb|S[
HibernateException { p_(En4QSH
String querySentence = "FROM user in class lZuH:AH
rwVp}H G
com.adt.po.User WHERE user.name=:name"; reNf?7G+m
Query query = getSession().createQuery [sjkm+
?
% P Ex
(querySentence); EZN!3y| m
query.setParameter("name", name); g8l6bh$}
return query.list(); H%X F~tF:
} l?
U!rFRq`
E3l*_b0
/* (non-Javadoc) ":vEWp+g
* @see com.adt.dao.UserDAO#getUserCount() 7RWgc]@?>
*/ El@*Fo
publicint getUserCount()throws HibernateException { k|\M(Z*(P
int count = 0; V.z8
]iG
String querySentence = "SELECT count(*) FROM wMj#.Jh
;kY~-Om
user in class com.adt.po.User"; /aMOZ=,q}
Query query = getSession().createQuery aWlIq(dU
hxK;f
(querySentence); \xbUr`WBY
count = ((Integer)query.iterate().next \hZ%NLj
ZZ!">AN`^
()).intValue(); 8I *N
return count; * m^\&
} vy*-"=J
D%nd7
|
/* (non-Javadoc) gFKJbjT|
* @see com.adt.dao.UserDAO#getUserByPage M:{Aq&.
S,nELV~!
(org.flyware.util.page.Page) )-emSV0zE
*/ ]/H6%"CTa
publicList getUserByPage(Page page)throws /KX+'@
:>2wVN&\c
HibernateException { !&>`
String querySentence = "FROM user in class u\L}B!
^a_a%ws
com.adt.po.User"; 4k-Ak6s
Query query = getSession().createQuery $\Y&2&1s
pITF%J@_]
(querySentence); xE
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query.setFirstResult(page.getBeginIndex()) Pv/v=s>X
.setMaxResults(page.getEveryPage()); XWnP(C9?
return query.list(); w$6Z}M1d
} [)1vKaC
kI)}7e
} vM6W64S
gWGDm~+
`vgaX,F*
[GI~ &
5N;'CAk
至此,一个完整的分页程序完成。前台的只需要调用 Mh4MaLw
D,ZLo~
userManager.listUser(page)即可得到一个Page对象和结果集对象 |DJ8
"T]E
Leb|YX
的综合体,而传入的参数page对象则可以由前台传入,如果用 DkEv1]6JI_
T1$E][@Iv
webwork,甚至可以直接在配置文件中指定。 p>;@]!YWQ
=I546($
下面给出一个webwork调用示例: ;6Yg}L
java代码: LCH\;07V#
wuA?t
gK`w|kh`
/*Created on 2005-6-17*/ ,M;9|kE*
package com.adt.action.user; Vv}R
S@4U
LK~aLa5wG
import java.util.List; 8ROKfPj;z
p8_^6wfg
import org.apache.commons.logging.Log; ]*\MIz{56'
import org.apache.commons.logging.LogFactory; hj9TiH/+
import org.flyware.util.page.Page; Td|u@l4B
GQn:lu3j:
import com.adt.bo.Result; oNyYx6q:Q
import com.adt.service.UserService; W&*&O,c
import com.opensymphony.xwork.Action; z{
:;Rb
'R79,)|;[
/** :xPo*#[Z(A
* @author Joa "mW'tm1+
*/ oNAnJ+_
publicclass ListUser implementsAction{ igfQ,LWe!
|(z{)yWbC[
privatestaticfinal Log logger = LogFactory.getLog b4e~Z
%- 540V{q
(ListUser.class); *y?HaU
#`*uX6C
private UserService userService; j#n ]q{s4
UxTLr-db^
private Page page; !S':G
k.ou$mIY
privateList users; X3l>GeUi
/{i~-DVME
/*
dZ`Y>wH_
* (non-Javadoc) @%Ld\8vdfJ
* \Y)HSJR;e
* @see com.opensymphony.xwork.Action#execute() Z^&G9I#
*/ ~R
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publicString execute()throwsException{ T+}|$/Tv
Result result = userService.listUser(page); 'K ?h6?#
page = result.getPage(); S)W xTE9
users = result.getContent(); RW. qw4
return SUCCESS; 9efDM
} &-yRa45?
K
{'
atc
/** p|-MwCeH
* @return Returns the page. +?{"Q#.>;
*/ mrP48#Y+l
public Page getPage(){ )t|:_Z
return page; <eG| `
} f=F:Af!
A*y4<'}<
/** |q*yuK/
* @return Returns the users. c,~uurVi
*/ [`\VgKeu
publicList getUsers(){ AOR?2u
return users; i<^X z
} L7C ;l,ot
)}@D\(/@
/** ~v;I>ij
* @param page nHdQe
* The page to set. XHk"nbj
*/ xpR`fq
publicvoid setPage(Page page){ 1&=)Bxg4
this.page = page; Ek)drt7cy
} Z!"-LQJ
k<< x}=
/** VhUWws3E
* @param users hu}$ \
* The users to set. el9P@r0
*/ E )_n?>Ar
publicvoid setUsers(List users){ Fc1!i8vv
this.users = users; 6<];}M_{
} v1OVrk>s>
JQ1MuE'
/** ]/=R ABi
* @param userService S0^a)#D &
* The userService to set. 7S a9
*/ C
t,p
publicvoid setUserService(UserService userService){ ^^N|:80
this.userService = userService; Jl~ *@0(
} ( eTrqI`
} zC2:c"E
I
BPO5=]W 7
X0;u7g2Yz
=0ZRGp
!?P8[K
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, xuK"pS
\?xM%(:<Q
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 V"YeF:I
A(FnU:
么只需要: )^ah, ;(
java代码: [CJ<$R !
^K?-+
d?fS#Ryb
<?xml version="1.0"?> k[r^@|
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork vE:*{G;Y
keAoJeG,J
1.0//EN" "http://www.opensymphony.com/xwork/xwork- EQm{qc;
&: Q'X
1.0.dtd"> a^R?w|zCX
Bh3F4k2bg7
<xwork> W8d-4')|
!Km[Qw
k-
<package name="user" extends="webwork- eYUb>M)
V]zc-gYI
interceptors"> &<F9Z2^
l_h:S`z.
<!-- The default interceptor stack name :ppaq
I&1Lm)W&
--> YYe G9yR
<default-interceptor-ref P.]h`4
=^4Z]d
name="myDefaultWebStack"/> ;st0Ekni)
r<vMp'u
<action name="listUser" ZNQx;51
5CY%h
class="com.adt.action.user.ListUser"> [neuwdN
<param E5ce=$o
"-Q+!byh
name="page.everyPage">10</param> /lBK )(
<result ~lj[> |\Oj
E 2nz
name="success">/user/user_list.jsp</result> ? o"
Vkc:
</action> W"NI^OX
K[z)ts-
</package> *Al@|5
>d + }$dB
</xwork> b$_81i
7gC?<;\0
!.vyzCJTzB
r:H]`Uo'r
>#]A2,
[H h-F#|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 &K/?#
i7Qb~RW
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。 KQ\K:#
z<%P"
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Nr4}x7
#V>R#Oh}
f'*-<sSr
!&:=sA
m}"Hm(,6
我写的一个用于分页的类,用了泛型了,hoho eEZgG=s
Pq /5Dy
java代码: (0 T!-hsP
0m_yW$w
)3h\QE!z
package com.intokr.util; sYKx3[ V/
AQ,lLn+
import java.util.List; ;(i6 X)
+mocSx[
/** <M:BN6-yG
* 用于分页的类<br> 7e"}ojt$
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 8['R D`O
* .+:iAnf
* @version 0.01 Q#eMwM#~
* @author cheng T[\1=h]
*/ HI8mNX3 "j
public class Paginator<E> { '`jGr+K,wU
privateint count = 0; // 总记录数 :v^/k]S
privateint p = 1; // 页编号 D3o,2E(o
privateint num = 20; // 每页的记录数 > 80{n8
privateList<E> results = null; // 结果 /!5Wd(:
] ?DU8
/** m{q'RAw
* 结果总数 (:l6R9'=
*/ 5JzvT JMx
publicint getCount(){ n>'(d*[e&
return count; S=qh7ML
} KFrsXf
$)M3fZ$#
publicvoid setCount(int count){ )iN;1>
this.count = count; f}-'67*Y
} <i~xJi%1#
\J^#2{d
/** 8C3k:
D[
* 本结果所在的页码,从1开始 tMl y*E
* Bu:%trlgV
* @return Returns the pageNo. Ln>!4i+-B)
*/ -@> {q/
publicint getP(){ i2<z"v63
return p; GHv6UIe&
}
x=*Y|
*Soi
/** Tz,-~ mc
* if(p<=0) p=1 `O\>vn
* ;<+efYmyc
* @param p e;.,x 5+
*/ X$kLBG[o_
publicvoid setP(int p){ ~~>m
if(p <= 0) !5*VBE\
p = 1; p4VARAqi
this.p = p; I*rUe#$
} kvbZx{s
!JCs'?A
/** 7By7F:[ b
* 每页记录数量 ?|M-0{
*/ L( 6b2{"
publicint getNum(){ !f~a3 {;j
return num; R~g|w4a@sC
} !gXxM,R
\+o\wTW
/** fK/:
* if(num<1) num=1 iYXD }l;r
*/ m212
gc0u
publicvoid setNum(int num){ vXKL<