Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 z,f=}t[.Y
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 I6w~H?ul@*
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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 >Pal H24]
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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 d?L\pN&
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分页支持类: sQ1jrkm
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java代码: "Pc$\zJm;
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package com.javaeye.common.util; WjMRH+
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import java.util.List; Of7+/UV
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publicclass PaginationSupport { 6m`{Z`c$
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publicfinalstaticint PAGESIZE = 30; 0Xl%uF+w
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privateint pageSize = PAGESIZE; :pC;`iQ
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privateList items; ;!u;!F!i
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privateint totalCount; UH3t(o7O
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privateint[] indexes = newint[0]; , Ww
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privateint startIndex = 0; le
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public PaginationSupport(List items, int g1[&c+=U`P
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totalCount){ z;3NiY
setPageSize(PAGESIZE); k*$3i
setTotalCount(totalCount); F]=B'ZI
setItems(items); yI8tH!
setStartIndex(0); #@//7Bf%
} +"!aM?o
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public PaginationSupport(List items, int Dn;p4T@
S*t%RZ~a
totalCount, int startIndex){ /L~m#HxWU
setPageSize(PAGESIZE); ;A#~`P
setTotalCount(totalCount); =!0I_L/
setItems(items); HD-Erop
setStartIndex(startIndex); Y E1Hpeb
} T@48 qg
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public PaginationSupport(List items, int tYe:z:7l?<
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totalCount, int pageSize, int startIndex){ #gv4
setPageSize(pageSize); A WJWtUa
setTotalCount(totalCount); v5$s#f<
setItems(items); TSto9$}*
setStartIndex(startIndex); Z9
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} a G27%(@
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publicList getItems(){ R]L2(' B
return items; ]PS\#I}
} r"_Y3SxxL
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publicvoid setItems(List items){ WZ~> BM
this.items = items; ]PX}b
} \{v,6JC
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publicint getPageSize(){ x)viY5vjH
return pageSize; BQNp$]5s
} .Ff_s
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publicvoid setPageSize(int pageSize){ 6
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this.pageSize = pageSize; ^.HWkS`e
} -2*>`,Uu
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publicint getTotalCount(){ 8(lCi$
return totalCount; jnBC;I[:
} i21QJ6jPcI
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publicvoid setTotalCount(int totalCount){ uiMIz?+
if(totalCount > 0){ 04JT@s"o
this.totalCount = totalCount; Eo=HNe
int count = totalCount / ]|LgVXEpx
p24.bLr
pageSize; 8/q*o>[?
if(totalCount % pageSize > 0) yazZw}};
count++; _*`q(dYcf
indexes = newint[count]; ?5~!i9pY
for(int i = 0; i < count; i++){ VGJDqm!
indexes = pageSize * gWu"91Y0>
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i; x[Q&k[xV
} {B^pnLc
}else{ JQT4N[rEE
this.totalCount = 0; .^H1\p];Lw
} r@|ZlM@O
} A- 0m8<
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publicint[] getIndexes(){ vKkf2 7
return indexes; SALCuo"L
} J/7u7_
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publicvoid setIndexes(int[] indexes){ Xz* tbW#
this.indexes = indexes; Ar5JP_M`E
} %kW3hQ<$
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publicint getStartIndex(){ R `Q?J[e
return startIndex; G5+]DogS
} 9OZ>y0)K~
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publicvoid setStartIndex(int startIndex){ gTD%4V
if(totalCount <= 0) =U_@zDD@V
this.startIndex = 0; ZjavD^ky
elseif(startIndex >= totalCount) HnK/A0jM
this.startIndex = indexes dw99FA6
5j1 IH,yW
[indexes.length - 1]; p1?J
elseif(startIndex < 0) a;yV#Y
this.startIndex = 0; f>4+,@G
else{ ds')PIj
this.startIndex = indexes d-i&k(M
|{!Ns +'
[startIndex / pageSize]; :z124Zf
} WiwwCKjSa
} i*b4uHna
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publicint getNextIndex(){ 10TSc
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int nextIndex = getStartIndex() + bY&YSlO
`7$Oh{67
pageSize;
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if(nextIndex >= totalCount) ^EUQ449<p
return getStartIndex(); ^CX,nj_(
else /Sh4pu"'
return nextIndex; *fOIq88
} MIJ%_=sm4:
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publicint getPreviousIndex(){ >:fJhF@
int previousIndex = getStartIndex() - Qvs(Rt3?y
WT1q15U(=
pageSize; *IVD/9/
if(previousIndex < 0) ^
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return0; XSls]o
s
else -MsuBf
return previousIndex; @US '{hO1p
} ~.!?5(AH8z
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} WVsKrFZT
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抽象业务类 W>VAbm
java代码: >02i8:Tp5K
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/** ?WMi S]Q\
* Created on 2005-7-12 _4!7
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*/ O]4W|WI3
package com.javaeye.common.business; #SK#k<&P
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import java.io.Serializable; #{?m
import java.util.List; R|6RI}
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import org.hibernate.Criteria; >^sz5d+X
import org.hibernate.HibernateException; aB7d(
import org.hibernate.Session; XC57];-
import org.hibernate.criterion.DetachedCriteria; U8Cw7u2
import org.hibernate.criterion.Projections; pC55Ec<
import lxr@[VQ
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org.springframework.orm.hibernate3.HibernateCallback; l6yB_M
import `W
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org.springframework.orm.hibernate3.support.HibernateDaoS lS>=y#i3Xv
AW]("pt
upport; IZzhJK M1V
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import com.javaeye.common.util.PaginationSupport; Y^T-A}?`
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public abstract class AbstractManager extends B6^w{eXN
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HibernateDaoSupport { M^0w/
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privateboolean cacheQueries = false; ^Osd/g
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privateString queryCacheRegion; l;.[W|
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publicvoid setCacheQueries(boolean ~Q3WBOjn
}6yxt9
cacheQueries){ Q';\tGy
this.cacheQueries = cacheQueries; 5EVB27k
} D>,$c
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publicvoid setQueryCacheRegion(String rin >r0o
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queryCacheRegion){ 1gf/#+$\
this.queryCacheRegion = ]Hv*^Bak
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queryCacheRegion; Q-H=wJ4R
} ./aZV
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publicvoid save(finalObject entity){ 9`hpa-m@
getHibernateTemplate().save(entity); *q\HFI
} #khyy-B=
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publicvoid persist(finalObject entity){ =[v2
getHibernateTemplate().save(entity); znGZULa#
} CfazD??x
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publicvoid update(finalObject entity){ N9fUlXhR
getHibernateTemplate().update(entity); WzNG<rG
} R|cFpRe
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publicvoid delete(finalObject entity){ u|:UFz^p
getHibernateTemplate().delete(entity); CfWK6 >
} %-0em!tUV
Q_UCF'f;}
publicObject load(finalClass entity, [:/7OM
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finalSerializable id){ &@`H^8
return getHibernateTemplate().load 3P=Eb!qtdD
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(entity, id); ~7eUt^SD;
} qHcY
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publicObject get(finalClass entity, ;mM\,
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finalSerializable id){ ={wjeRp
return getHibernateTemplate().get O(:u( U7e
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(entity, id); JXRmu~W~l
} :IOn`mRYu
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publicList findAll(finalClass entity){ &T|UAM.
return getHibernateTemplate().find("from tCF0Ah
$bM#\2'
" + entity.getName()); ta+"lM7A}$
} L?/M2zc9Y
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publicList findByNamedQuery(finalString ?U2g8D nFY
{H"=PYR
namedQuery){ WZDokSR
return getHibernateTemplate Z_hBd['!
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().findByNamedQuery(namedQuery); : \ON+LQr
} 8B% O%*5`
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publicList findByNamedQuery(finalString query, RvgAI`T7$
q>Ar.5&M_
finalObject parameter){ `G:qtHn"Q<
return getHibernateTemplate ?_<UOb*
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().findByNamedQuery(query, parameter); da7x 1n$D
} ]pucv!
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publicList findByNamedQuery(finalString query, FC/>L
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finalObject[] parameters){ o*5e14W(:
return getHibernateTemplate ~[bMfkc3
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().findByNamedQuery(query, parameters); _dRn0<#1(k
} Lqf#,J
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publicList find(finalString query){ pCud`
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return getHibernateTemplate().find ZLFdnC@
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(query); cJp1 <R
} pdXgr)Uv
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publicList find(finalString query, finalObject J*W;{Vty
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parameter){ @bVh?T0~F,
return getHibernateTemplate().find |^&2zyUj/
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(query, parameter); }E\+e!'!2
} 5qAE9G!c
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public PaginationSupport findPageByCriteria xQ(KmP2hl
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(final DetachedCriteria detachedCriteria){ nR|uAw
return findPageByCriteria (>@syF%PB
e]y=]}A3{
(detachedCriteria, PaginationSupport.PAGESIZE, 0); 8G^B%h]
} qI/r_
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public PaginationSupport findPageByCriteria
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(final DetachedCriteria detachedCriteria, finalint aN);P>
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startIndex){ i|! 9o:
return findPageByCriteria g he=mQ-
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(detachedCriteria, PaginationSupport.PAGESIZE, AK\g-]8
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startIndex); sN an"
} 9!/1F !
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public PaginationSupport findPageByCriteria `[HoxCV3o
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(final DetachedCriteria detachedCriteria, finalint n;T
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pageSize, =R8.QBVdN
finalint startIndex){ sMpC4E
return(PaginationSupport) )<&CnK
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getHibernateTemplate().execute(new HibernateCallback(){ \iTPJcb5
publicObject doInHibernate p]IhQnj2
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(Session session)throws HibernateException { m_O=X8uj"D
Criteria criteria = 'MM~~:
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detachedCriteria.getExecutableCriteria(session); 'H-YFB$l
int totalCount = t6>Qe
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((Integer) criteria.setProjection(Projections.rowCount [Kj#KJxy
F v^80M=z
()).uniqueResult()).intValue(); Spw=+z<<Ub
criteria.setProjection P`Wf'C^h
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(null); U~`^Y8UF
List items = w5JC 2
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criteria.setFirstResult(startIndex).setMaxResults tNNg[;0
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sx/
(pageSize).list(); l4.@YYzbp.
PaginationSupport ps = 0JWD] "
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new PaginationSupport(items, totalCount, pageSize, .Im+()b&&
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startIndex); F$.s6Hh.
return ps; ENF@6]
} 6!L*q
}, true); @T=HcUP)
} rQ-z2Pw
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public List findAllByCriteria(final ?ut juMdl
.&!{8jBX
DetachedCriteria detachedCriteria){ qk{UO
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return(List) getHibernateTemplate [#h!3d|?B
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().execute(new HibernateCallback(){ +?g,&NE
publicObject doInHibernate \}Kp=8@nE
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(Session session)throws HibernateException { +P;D}1B#I?
Criteria criteria = 7^e}|l
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detachedCriteria.getExecutableCriteria(session); 1OwkLy,P
return criteria.list(); X#C7r@H
} X{5 DPhB,
}, true); $GKm`I"
} e<wj5:M|
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public int getCountByCriteria(final u5|e9(J
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DetachedCriteria detachedCriteria){ ~(E8~)f)
Integer count = (Integer) f9bz:_;W_
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getHibernateTemplate().execute(new HibernateCallback(){ 2gI_*fG1
publicObject doInHibernate C+IE<=%F
cr;`0
(Session session)throws HibernateException { M|]1}8d?
Criteria criteria = I%WK*AORM
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detachedCriteria.getExecutableCriteria(session); ="eum7
return ]ZATER)jq
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criteria.setProjection(Projections.rowCount &H>dE]Hq,
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()).uniqueResult(); c&W.slE6
} DLM9o3/*J
}, true); 8-l Y6M\R\
return count.intValue(); 51'SA
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} 'a[|}nJ3
} c324@o^V
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用户在web层构造查询条件detachedCriteria,和可选的 4V3
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 !/Ps}.)A`
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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 $yK!Q)e:
ps.getIndexes()得到分页索引的数组 p~co!d.q/}
ps.getTotalCount()得到总结果数 @]3Rw[%z
ps.getStartIndex()当前分页索引 e)(|
ps.getNextIndex()下一页索引 J8DbAB4X
ps.getPreviousIndex()上一页索引 8dB~09Z7
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 3?(p;
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 _q$fw&
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一下代码重构了。 O{R5<"g
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我把原本我的做法也提供出来供大家讨论吧: FI5C&d5d
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首先,为了实现分页查询,我封装了一个Page类: 7T Bo*-!
java代码: cyE2=
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/*Created on 2005-4-14*/ h;M2ylOu.
package org.flyware.util.page; O~xmz!?=
#4u; `j"4=
/** i%
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* @author Joa I\23as0q
* ufPQ~,.
*/ TZ2f-KI
publicclass Page { s30_lddD
Q.AM
/** imply if the page has previous page */ !m2k0|9
privateboolean hasPrePage; q Q8l8
5al{[mi
/** imply if the page has next page */ Shd,{Z)-Tg
privateboolean hasNextPage; }YO}LQ-|
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/** the number of every page */ PEl]HI_H
privateint everyPage; 7A-rF U$
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/** the total page number */ vm4oaVi
privateint totalPage; W'$~mK\
`s $@6r$
/** the number of current page */ 6u}NI!he
privateint currentPage; `yXy T^
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/** the begin index of the records by the current 5i?U-
0=DawJ9
query */ I,;)pWX=@
privateint beginIndex; )O
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t |h mEHUk
bwFc>{Wo5
/** The default constructor */ |VL,\&7rk
public Page(){ GAlO<Mu
KRe=n3 1
} }D O# {@af
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/** construct the page by everyPage Y."[k&P-
* @param everyPage ja2]VbB
* */ dr o42#$Mo
public Page(int everyPage){ op C11c/
this.everyPage = everyPage; A9gl|II
} iz(+(M
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/** The whole constructor */ !%@{S8IP.v
public Page(boolean hasPrePage, boolean hasNextPage, ;4IP7$3G
c[$oR,2b13
\m!."~%
int everyPage, int totalPage, 6dUP's_
int currentPage, int beginIndex){ H<yec"
this.hasPrePage = hasPrePage; JGe;$5|q8
this.hasNextPage = hasNextPage; 2<|5zF
this.everyPage = everyPage; m}(DJ?qP
this.totalPage = totalPage; G#Ow>NJ
this.currentPage = currentPage; Y# #J
this.beginIndex = beginIndex; ~Zm(p*\T
} 4`F*] Ft
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/**
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* @return 5UbVg
* Returns the beginIndex. $;1~JOZh
*/ 9[*kpMC
publicint getBeginIndex(){ \=<.0K A~
return beginIndex; 6>Y}2fT}o3
} z6qC6Ck|
&.,OvVAo
/** W8^gPW*c5
* @param beginIndex tWFJx}H
* The beginIndex to set. "$&F]0
*/ "<WSEs
publicvoid setBeginIndex(int beginIndex){ 2h!3[{M\
this.beginIndex = beginIndex; ?H`LrL/k
} V1G]LM
N\?iU8w=
/** Y>+D\|%Q
* @return c#DTL/8"DO
* Returns the currentPage. )".gjW8{#L
*/ 4\?B,!
publicint getCurrentPage(){ o%.cQo=v*
return currentPage; Ow
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} U#}.r<
e_TM#J(3
/** ".u?-xcbJ
* @param currentPage 0AEs+=
* The currentPage to set. aZRgd^4
*/ K*<n<;W
publicvoid setCurrentPage(int currentPage){ 9=SZL~#CE
this.currentPage = currentPage; [xC
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} L{-w9(S`i
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/** PD?H5W3@
* @return u+'=EGl
* Returns the everyPage. [F%\1xh
*/ %YXC-E3@O
publicint getEveryPage(){ -~q]0>
return everyPage; o\#C] pp
} R&QT
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/** ]V_9[=%
* @param everyPage 0)B+:
* The everyPage to set. MouYZI)
*/ KK+Mxoj,
publicvoid setEveryPage(int everyPage){ 0-9&d(L1g
this.everyPage = everyPage; s$en5)
}
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/** d2Y5'A0X
* @return ICi- iX
* Returns the hasNextPage.
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*/ NXx}KF c
publicboolean getHasNextPage(){ /_O-m8+4m
return hasNextPage; TaC)N
} 5?O"N
=pNkS1ey
/** F8/@/B
* @param hasNextPage `y\:3bQ4
* The hasNextPage to set. 4u&doSXR
*/ 4aRYz\yT=
publicvoid setHasNextPage(boolean hasNextPage){ BhKxI
this.hasNextPage = hasNextPage; bk<3oI
} dM') <lF
t*x;{{jL#(
/** %(E6ADB
* @return +[ F8>9o&
* Returns the hasPrePage. s{/nO)
*/ {^qc`oF
publicboolean getHasPrePage(){ Eq?o/'e
return hasPrePage; fTeo,N
} )Mok$
EW`3h9v~
/** !|!V}O
* @param hasPrePage $`
* The hasPrePage to set. >C i=H(8vN
*/ mF1oY[xa_
publicvoid setHasPrePage(boolean hasPrePage){ &ke4":7X
this.hasPrePage = hasPrePage;
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} E.}Zmr#H
$W09nz9?
/** li{_biey}
* @return Returns the totalPage. y8L:nnSj
* VltWY'\Wu;
*/ [B4?Z-K%
publicint getTotalPage(){ d_`Ze.^
return totalPage; 0jXIx2y
} ofSOy1
6f?DW-)jp/
/** exhF5,AW|K
* @param totalPage Qhr:d`@^]
* The totalPage to set. 4k#6)e
*/ zumRbrz
publicvoid setTotalPage(int totalPage){ M3Z yf
this.totalPage = totalPage; 6k[u0b`
} NOx|
#
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} ,9rT|:N
1/i|
'L,rJ =M3
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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 >}9TdP/oT
YGHWO#!Gp
个PageUtil,负责对Page对象进行构造: 2PC4EjkC
java代码: 7+ysE
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#Kl;iY:n
/*Created on 2005-4-14*/ 8P*n|]B.'
package org.flyware.util.page; n0m9|T&
cO8;2u,Gvi
import org.apache.commons.logging.Log; i{8=;
import org.apache.commons.logging.LogFactory; [bcqaT
;?&;I!
/** 'W#<8eJo
* @author Joa l]ZUKy
* }YjSv^
*/ d/^^8XUK
publicclass PageUtil { VTHDGBU
j7W_%Yk|E
privatestaticfinal Log logger = LogFactory.getLog l>G#+#{
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(PageUtil.class); 9\xw}ph
O$$N{
/** '!0CwZ
7
* Use the origin page to create a new page jIl-}/2
* @param page x:2_FoQ
* @param totalRecords -P?}
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* @return Z+}SM]m
*/ +vuW9
publicstatic Page createPage(Page page, int yT>T
Vq/e
;?cUF78#
totalRecords){ Tx xc-$z
return createPage(page.getEveryPage(), :G-1VtE n
&dS+!<3
page.getCurrentPage(), totalRecords); csV1ki/A
} &Jn%2[;
]_Qc}pMF&
/** YlA=?
X
* the basic page utils not including exception Bm?Ku7}.
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handler X6;aF;"5
* @param everyPage Y~C S2%j
* @param currentPage EKt-C_)U
* @param totalRecords eDm,8Se
* @return page ]gEfm~YV
*/ XyI w5
9
publicstatic Page createPage(int everyPage, int A(uN=r@O
<L`R!}
currentPage, int totalRecords){ OJK/>
everyPage = getEveryPage(everyPage); +VeLd+Q}
currentPage = getCurrentPage(currentPage); crT[;w
int beginIndex = getBeginIndex(everyPage, qm '$R3g
p?`N<ykF<
currentPage); 9O)>>1}*S
int totalPage = getTotalPage(everyPage, @@$
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EZHEJW'JnE
totalRecords); cD>o(#x]
boolean hasNextPage = hasNextPage(currentPage, {> }U>V
AE$)RhY`
totalPage); upJishy&I
boolean hasPrePage = hasPrePage(currentPage);
[
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UOY1^wY
returnnew Page(hasPrePage, hasNextPage, UWnH2
everyPage, totalPage, T;% SB&
currentPage, ^?A+`1-
{L0w&~$Fy
beginIndex); ,t[D1KZt
} +2g3%c0}
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privatestaticint getEveryPage(int everyPage){ iO@wqbg$6
return everyPage == 0 ? 10 : everyPage; ^Nu} HcC+
} (UM+?]Qwy
?R+$4;iy
privatestaticint getCurrentPage(int currentPage){ Jq!($PdA
return currentPage == 0 ? 1 : currentPage; `Ctj]t
} Y}6)jzBV
UvI!e4_
privatestaticint getBeginIndex(int everyPage, int aZ^lI
6@+4
^>"?!lv
currentPage){ aJF`rLm
return(currentPage - 1) * everyPage; |WX4L7yrhK
} i!iODt3k
v!uLd.(
privatestaticint getTotalPage(int everyPage, int pg<>Ow5,~l
,..b)H5n
totalRecords){ [q@%)F
int totalPage = 0; 4EK[gM8
$X?V_K;9/
if(totalRecords % everyPage == 0) Nh))U
totalPage = totalRecords / everyPage; BO_^3Me*
else rQqtejcfx
totalPage = totalRecords / everyPage + 1 ; NplSkv
!9
F+uc5
return totalPage; 9p.>L8
}
pGFocw
t0q@]
0B5
privatestaticboolean hasPrePage(int currentPage){ Xx^c?6YM
return currentPage == 1 ? false : true; jDnh/k0{d
} E=E<l?ob
AM[:Og S
privatestaticboolean hasNextPage(int currentPage, *"
)[Srbg
Yem\`; *
int totalPage){ )\(pDn$W
return currentPage == totalPage || totalPage == jt3SA
[cy
j{=%~
0 ? false : true; 2S;zze7)
} `et<Z
*v9G#[gG
[>0r'-kI
} +M*a.ra0OF
8M|Q^VeT,1
,aJrN!fzU
vEsSqzc
2R!W5gs1<
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 }FXRp=s
3XRG"
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 */)gk=x8
U`Zn*O~/
做法如下: q~3&f
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 lySa Jd
NSq"\A\
的信息,和一个结果集List: -AE/,@ \P
java代码: G!\xc
S%oGBY*Z
v<wT`hiKW
/*Created on 2005-6-13*/ R32d(2%5K
package com.adt.bo; z-DpLV
&u8c!;y$b
import java.util.List; "DpQnhvbB
JF
gN
import org.flyware.util.page.Page; #t
O!3= 0
Pz 'Hqvd
/** ?<;<#JN
* @author Joa ?KN_J
*/ =X*E(.6Ip
publicclass Result { Fo#*_y5\
b ~gF,^w
private Page page; .kIf1-(<U
xh0A2bw'OP
private List content; s__g*%@B
b
5IK@<#wE
/** *QG;KJ%
* The default constructor s<b7/;w'
*/ 6,PLzZ5
public Result(){ 3[0:,^a
super(); je-s%kNlJ
} Q1Ao65
l&B'.6XKs
/** ~}w 8UO
* The constructor using fields bRp[N
* WQx;tX
* @param page KfNXX>'
* @param content %u}sVRJ
*/ \4k*Zk
public Result(Page page, List content){ In&vh9Lw
this.page = page; %a `dOEO
this.content = content; k:Q<Uanc[
} 3:Wr)>l}#
gwJu&HA/
/** K}BX6dA
* @return Returns the content. w C"%b#(}
*/ S41>VbtEp
publicList getContent(){ P{18crC[1
return content; SO/]d70HG
} pZxL?N!
; \+0H$
/** *q{UipZbx
* @return Returns the page. $Stu-l1e a
*/ =Qrz|$_rv
public Page getPage(){ OB22P%
return page; ?sYjFiE
} &v,p_'k
Hea<!zPH
/** hT"K}d;X
* @param content E6M: ^p*<
* The content to set. _ GSw\r
*/ N/BU%c
ph+
public void setContent(List content){ gN~y6c:N
this.content = content; H%]ch6C
} N &=2 /
|U
$-d^ZJ
/** tpONSRY
* @param page <>s\tJ
* The page to set. sdQv:nd'R
*/ lvi:I+VgA
publicvoid setPage(Page page){ JB@VP{
this.page = page; U I C? S
} ,~(}lvqVH
} G`"Cqs<
uszSFe]E
)AXH^&
}3w b*,Sbz
VhgEG(Ud
2. 编写业务逻辑接口,并实现它(UserManager, WmUW
i{
A#&qoZ(C
UserManagerImpl) Ir #V2]$
java代码: R"`{E,yj
:'~ gLW>j
"b4iOp&:=
/*Created on 2005-7-15*/ om?CFl
package com.adt.service; yXg1N
N
u^%')Ncp
import net.sf.hibernate.HibernateException; /}_c7+//
q}Z
T?Xk?
import org.flyware.util.page.Page; 7G/|e24
Ws)X5C=A
import com.adt.bo.Result; p]Zabky
tY'QQN||
/** 4&hqeY3
* @author Joa /
LM
*/ -oBas4J
publicinterface UserManager { yMl'1W
)O C[;>F7
public Result listUser(Page page)throws 3z92Gy5cr
% T \N@
HibernateException; sA-W^*+
U^BXCu1km
} 2 _n*u^X:_
3Lki7QW`
ok%!o+nk.
;<@6f @
rq["O/2
java代码:
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{))S<_yN
OG7v'vmY
/*Created on 2005-7-15*/ UQ])QTrZFi
package com.adt.service.impl; zB"
`i
EZQ+HECpK
import java.util.List; ~PW}sN6ppG
hRIS[#z;U
import net.sf.hibernate.HibernateException; <<5 :zlb
|!5T+H{Sj
import org.flyware.util.page.Page; 5|G3t`$pa
import org.flyware.util.page.PageUtil; #aY<J:Nx
1[g!^5W
import com.adt.bo.Result; Fi%W\Y'
import com.adt.dao.UserDAO; ~Z6p3#
!o
import com.adt.exception.ObjectNotFoundException;
I S8nvx\
import com.adt.service.UserManager; u;ooDIq@
Bye@5D
/** =z1o}ga=EA
* @author Joa m$mY<Q
*/ f\_!N
"HW
publicclass UserManagerImpl implements UserManager { vLFaZ^(
LiD |4(3
private UserDAO userDAO; RG
r'<o )
Po11EZa$a
/** -s%-*K+,W
* @param userDAO The userDAO to set. WfT)CIKs
*/ iSz@E&[X
publicvoid setUserDAO(UserDAO userDAO){ m2q;^o:J
this.userDAO = userDAO; o / g+Z
} fMEv85@JL
aU<D$I
/* (non-Javadoc) *8X9lv.Z
* @see com.adt.service.UserManager#listUser \.;ct
G<-9U}~76
(org.flyware.util.page.Page) yX.5Y|A<
*/ d3=6MX[c
public Result listUser(Page page)throws UoMWn"ZE
NU&^7[!yl
HibernateException, ObjectNotFoundException { x$?7)F&z
int totalRecords = userDAO.getUserCount(); LF)a"Sh
if(totalRecords == 0) \P~rg~
throw new ObjectNotFoundException hf+/kc!>i
K1/gJ9+(\
("userNotExist"); {&}/p-S
page = PageUtil.createPage(page, totalRecords); 4IP\iw#w
List users = userDAO.getUserByPage(page); j)tCr Py
returnnew Result(page, users); /z)3gsF
} @S"pJeP/f
a3dzok
} Hl2f`GZ
CpRu*w{
R!k<l<9q
R-A'v&=
2u*h*/
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 B?lBO
V4v4
g3~~"`2
询,接下来编写UserDAO的代码: :O'C:n<g
3. UserDAO 和 UserDAOImpl: Uq]EJu
java代码: Fwx~ ~"I
MHnf\|DX
5
2@udp
/*Created on 2005-7-15*/ nl-t<#z[
package com.adt.dao; Q_]!an(
#S53u?JV8
import java.util.List; xngeV_xc2
bg1"v a#2
import org.flyware.util.page.Page; 1;Wkt9]9
()nKug`.@
import net.sf.hibernate.HibernateException; j*H;a ?Y
\5_P5q:`
/** h%1~v$W`
* @author Joa `b.o&t$L
*/ qaMZfA
publicinterface UserDAO extends BaseDAO { 2c"N-c&A
H#|Z8^ *Ds
publicList getUserByName(String name)throws A
eGG
KI Plb3oh
HibernateException; (U(/C5'
+\k9w.[:/
publicint getUserCount()throws HibernateException; UR/qVO?
_<%\h?W$
publicList getUserByPage(Page page)throws L*
khj 3;
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HibernateException; B3cf] S%
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} ~X~xE]1o|U
iz9\D*or
}c35FM,
Z[})40[M
UVT>7
java代码: VA=#0w
M2;%1^
Esz1uty
/*Created on 2005-7-15*/ |B%BwE
package com.adt.dao.impl; `CAG8D
y|e2j&m
import java.util.List; rb *C-NutE
dXhCyr%"6
import org.flyware.util.page.Page; @~$F;M=.*
c_qcb7<~.
import net.sf.hibernate.HibernateException; Q/QQ:t<XUi
import net.sf.hibernate.Query; q ab)
1ft
VBbUl|X\
import com.adt.dao.UserDAO; u>,lf\Fgz
XN~#gm#
/** e0v9uQ%F5
* @author Joa dysX
*/ [j:}=:feQ
public class UserDAOImpl extends BaseDAOHibernateImpl ]r/(n]=(
v:veV. y
implements UserDAO { f.b8ZBNj>
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/* (non-Javadoc) ?JXBWB4
* @see com.adt.dao.UserDAO#getUserByName 670J{b
q)K-vt)98
(java.lang.String) j*;*Ka w
*/ Z7/vrME6
publicList getUserByName(String name)throws bK$/,,0=X/
JHvFIo
HibernateException { ``(}4a
String querySentence = "FROM user in class [^?13xMb
U OR _M5
com.adt.po.User WHERE user.name=:name"; }.fL$,7a
Query query = getSession().createQuery E/wQ+rv
,_.@l+BM.
(querySentence); 6C:x6'5[
query.setParameter("name", name); kf+JM/
return query.list(); q3c*<n g#
} Yw~;g:=
6?%]odI#
/* (non-Javadoc) ov\Ct%]
* @see com.adt.dao.UserDAO#getUserCount() F-$Z,Q]S
*/ 0M#N=%31
publicint getUserCount()throws HibernateException { nmD1C_&
int count = 0; YH<$ +U
String querySentence = "SELECT count(*) FROM X+`ddX
-@%t"8
user in class com.adt.po.User"; U9<_6Bsd
Query query = getSession().createQuery W:VW_3
*C4~}4WT\
(querySentence); q?;N7P
count = ((Integer)query.iterate().next
I6K7!+;2
-!XrwQyk
()).intValue(); 3
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~
return count; lp:_H-sG
} u{g]gA8s
:FoOQ[Q
/* (non-Javadoc) <WM -@J(1
* @see com.adt.dao.UserDAO#getUserByPage KH>Sc3p
`xISkW4 %
(org.flyware.util.page.Page) 2-8YSHlh
*/ *4|9&PNLE
publicList getUserByPage(Page page)throws hf_R\C(c
| f"-|6
HibernateException { &e%{k@
String querySentence = "FROM user in class @
\!KF*v
H,(F1+~d
com.adt.po.User"; 96vj)ql
Query query = getSession().createQuery -`-ACWeNV
ge^!F>whr
(querySentence); h^%GE;N
query.setFirstResult(page.getBeginIndex()) =RQ )$ %
.setMaxResults(page.getEveryPage()); .>k=A|3G
return query.list(); AU0$A403
} Q8 -3RgAw
ZvUp#8x(3
} 2#'rk'X,K
|d~B]65t
d>YmKTk"
+7Sf8tg\
&\&'L|0F
至此,一个完整的分页程序完成。前台的只需要调用 GMEw
NV&;e[z
userManager.listUser(page)即可得到一个Page对象和结果集对象 U^B"|lc:[
K{|w 43>D
的综合体,而传入的参数page对象则可以由前台传入,如果用 |)^clkuGX
:L]-'\y
webwork,甚至可以直接在配置文件中指定。 /pO{2[
:0B
|<~lX
下面给出一个webwork调用示例: |$M@09,F"
java代码: !-KCFMvT
'!pAnsXfO
2y^Uk,g
/*Created on 2005-6-17*/ M,&tA1CH
package com.adt.action.user; ;
Zh9^0
cE^kpnVq|<
import java.util.List; :[L{KFQU
~@xT]D!BQ
import org.apache.commons.logging.Log; D._{E*vg
import org.apache.commons.logging.LogFactory; U%Dit
import org.flyware.util.page.Page; j -#E?&2
0xN!DvCg>.
import com.adt.bo.Result; (2:
N;
import com.adt.service.UserService; : @s8?eg
import com.opensymphony.xwork.Action; +:}kZDl@ X
XxhsPFv
/** YQN.Ohtv*F
* @author Joa Z#CxQ D%\
*/ g+igxC}2z
publicclass ListUser implementsAction{ S<V-ZV&_:U
<BZ_ (H
privatestaticfinal Log logger = LogFactory.getLog 1d`cTaQ-
K-Re"zsz
(ListUser.class); 8098y,mQe
}(m1ql
private UserService userService; 4/b(Y4$,[r
,cLH*@
private Page page; g&Z"_7L~
N A8
sN
privateList users; S3ErH,XB.
`a-Bji?
/* %z30=?VL
* (non-Javadoc) gRHtgR)T3
* z3clUtC+
* @see com.opensymphony.xwork.Action#execute() 64SW
*/ \e_IFISC
publicString execute()throwsException{ {JXf*IJ
Result result = userService.listUser(page); aUAcRW
page = result.getPage(); D2{L=
users = result.getContent(); 2v4W6R
return SUCCESS; SBC~QD>L+
} ?fB5t;~E
K6-6{vt
/** FzVZs#O
* @return Returns the page. lBS"3s384
*/ \]t]#D>0
public Page getPage(){ 5~QhX22
return page; tbg*_ZQO u
} )Q~C4 C-j
F9%,MSt
/** w:v=se"U
* @return Returns the users. f#1/}Hq/I
*/ {y1q7Z.M
publicList getUsers(){ ti}f&w
ICJ
return users; Zgy7!AF!
} XJc
,uj7
C1tb`
/** \Fq1^ 8qa
* @param page hv3;irK]&
* The page to set. <Kg2$lu(_`
*/ ><cU7 ja[^
publicvoid setPage(Page page){ hzv3F9.x
this.page = page; v_.HGGS
} 0JK2%%
+N7"EROc
/** w\Iqzpikr
* @param users vf[&7n
* The users to set. \Y+")
*/ dIvy!d2l
publicvoid setUsers(List users){ RJ@\W=aZ
this.users = users; JwB"\&'1ZS
} cu)U7
@cPflb
/** Vu%n&uF
* @param userService YKY2Cw
* The userService to set. rmsQt
*/ &f"T,4Oh
publicvoid setUserService(UserService userService){ 7|Xe&o<n
this.userService = userService; L1:nfH&:'
} z{=v)F5y
} EZ/^nG
W+K.r?G<j
Xo\S9,s{
Yh$fQ:yi\&
drI\iae{^
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, h
D.)M
d+0^u(gc!8
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 nZxSMN0]
&8n?
么只需要: ?~Pv3'%d
java代码: &sdx`,
_KN:
o10U
Ev{MCu1!6
<?xml version="1.0"?> w:Ra7ExP
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork iy}xICt
Q(e{~
]*
1.0//EN" "http://www.opensymphony.com/xwork/xwork- O5M2`6|As
`w+1C&>^[
1.0.dtd"> J0sGvj{
YQYX,b
<xwork> modC6d%
"W5rx8a
<package name="user" extends="webwork- #3+~.,X9
l#$TYJi
interceptors"> NV6G.x
_4v"")Xe
<!-- The default interceptor stack name !VRo*[yD@
TM-Fu([LMV
--> AuXs B
<default-interceptor-ref W~yLl%
H{%H^t>
name="myDefaultWebStack"/> Zw#<E
=\
|mOMRP#'
<action name="listUser" :v)6gz(p
L#2ZMy
class="com.adt.action.user.ListUser"> Z9VR]cf?
<param [~)x<=H8{
M*(H)i;s:w
name="page.everyPage">10</param> \7 Gz\=\LR
<result 1O0X-C,wo$
8#l+{`$z
name="success">/user/user_list.jsp</result> /?P!.!W&
</action> @vt$MiOi
~j"3}wXc5
</package> 'fn$'CeM(
WqQU@sA
</xwork> $UC {"0
X3yS5whd(
}LQC.!
G?ig1PB"#
{m[Wyb(
n}q$f|4!
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 0X>T+A[E
uY]0dyI
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。 |'$ l7
?oKL&I@
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 R5kH0{zM
n"Z |e tZ4
Y{+3}drJE
9`Vc
:j,}{)5=
我写的一个用于分页的类,用了泛型了,hoho $DE&J4K
Y[um|M315
java代码: `{o$F ::(
RG}}Oh="v
,H{={aln
package com.intokr.util; d}+W"j;
QNpuTZn#Q
import java.util.List; J|5Ay1eF-
dB7ZT0L\
/** F 7LiG9H6`
* 用于分页的类<br> I_>`hTiR
* 可以用于传递查询的结果也可以用于传送查询的参数<br> SiTeB)/
* M1{(OY(G
* @version 0.01 s[X
B#)H4
* @author cheng x.UaQ |F
*/ #xp(B5
public class Paginator<E> { m9t$h
privateint count = 0; // 总记录数 g "*;nHI D
privateint p = 1; // 页编号
H=<LutnZ
privateint num = 20; // 每页的记录数 F#|Z# Mu
privateList<E> results = null; // 结果 RRzP*A%=
f GarUV
/** %b?uW]j:
* 结果总数 ="(>>C1-
*/ MGaiTN^_<
publicint getCount(){ +zp0" ,2B
return count; :0I
l|aB
} ;;Tq$#vd
;4kT?3$l
publicvoid setCount(int count){ g~)3WfC$[
this.count = count; Nw pS)6<-
} 1EsqQz*$u
^l(^z fsZ
/** ^P$7A]!
* 本结果所在的页码,从1开始 HeozJ^u\?
* r?3Aqi"
* @return Returns the pageNo. ?cK]C2Ak
*/ $5A^'q
publicint getP(){ ,g|2NjUAc
return p; i}lRIXjdV
} 0*yJ %
[h-norB((
/** kEP<[K
* if(p<=0) p=1 niWx^gKb$
* Pm?B
9S
* @param p #>[wD#XJV
*/ A3q*$.[
publicvoid setP(int p){ ch })ivFP[
if(p <= 0) >nM%p4E
p = 1; UA(;fZ@
this.p = p; ]w[ThHRJ
} A*i_|]Q
sE9Ckc5
/** *eGM7o*\X
* 每页记录数量 8x{Hg9
*/ BIfi:7I;Q
publicint getNum(){ %5Rq1 $D
return num; GOVAb'
} ti9}*8
;_tO+xL&
/** QO,+ps<
* if(num<1) num=1 ;k}H(QI
*/ m UgRm]
publicvoid setNum(int num){ /gw Cwyo
if(num < 1) i@,]Z~]
num = 1; *U_oao
this.num = num; E474l
} ( 3;`bvYH"
P']Y(
!L
/** *rf$>8~$n
* 获得总页数 aR)?a;}H
*/ *Hunp Y
publicint getPageNum(){ \ja `c)x
return(count - 1) / num + 1; GYoseqZM
} .'lN4x
&HL{LnLP@/
/** oD0EOT/E
* 获得本页的开始编号,为 (p-1)*num+1 H[nz]s
*/ L_?$ayZ;
publicint getStart(){ a5V=!OoMk
return(p - 1) * num + 1; o5 WW{)Q
} _9kIRmT{
}4h0bI
/** ym%o}(v-
* @return Returns the results. d~`-AC+
*/ W4vBf^eC
publicList<E> getResults(){ ' ^a!`"Bc
return results; ;rHz;]si
} /b{HG7i\
/aOlYqM(>
public void setResults(List<E> results){ C +@ i
this.results = results; fSI %c3
} * nCx[
9L HuS
public String toString(){ Tz` ,{k
StringBuilder buff = new StringBuilder g+|Bf&_
4_Y!el H)
(); 5;Ia$lm=y
buff.append("{"); N-QCfDao
buff.append("count:").append(count); `~nCbUUee
buff.append(",p:").append(p); =]b9X7}
buff.append(",nump:").append(num); gZ` DT
buff.append(",results:").append `bqzg
7$_
:sJ
(results); wd+O5Lr.R
buff.append("}"); .bfST.OA
return buff.toString(); H,|YLKg-|
} 4z0L ke
/ O)6iJ
} >{XScxaB`
!Uy>eji}
e1^l.>2d6