Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 oR<;Tr~{q
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 t@`Sa<
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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 Xkp`1UTH
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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 yfe4}0}
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。 [8`^_i=#
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分页支持类: Otm7j>w
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java代码: 8';huq@C{
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package com.javaeye.common.util; OV $|!n
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import java.util.List; i}ti
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publicclass PaginationSupport { 4:XVu
+}!FP3KgT
publicfinalstaticint PAGESIZE = 30; >zcp(M98
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privateint pageSize = PAGESIZE; KHt#mQy)9
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privateList items; @>hXh
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privateint totalCount; 7.1FRxS
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privateint[] indexes = newint[0]; C Z/:(sOJ
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privateint startIndex = 0; `v1~nNoY
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public PaginationSupport(List items, int 5B+I\f&
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totalCount){ 1FmqNf:V7I
setPageSize(PAGESIZE); "Bbd[ZI8
setTotalCount(totalCount); TY*q[AWG
setItems(items); LDq(WPI1#
setStartIndex(0); 3gU*,K7
} W2j@Q=YDS
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public PaginationSupport(List items, int (e6KSRh2fF
T6p2=o&p
totalCount, int startIndex){ BvV!?DY4
setPageSize(PAGESIZE); sD`OHV:
setTotalCount(totalCount); +%RB&:K7,
setItems(items); 5Gsjt+
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setStartIndex(startIndex); P0^7hSo
} y5lhmbl: e
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public PaginationSupport(List items, int :~+m9r
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totalCount, int pageSize, int startIndex){ (J/!9NS:
setPageSize(pageSize); p*S;4+>#
setTotalCount(totalCount); DANndXQLH
setItems(items); naB`@
setStartIndex(startIndex); @je vY81)
} 1brKs-z
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publicList getItems(){ TdH~sz
return items; BY^5z<^.
} i7(\i2_P
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publicvoid setItems(List items){ nH^RQ'19
this.items = items; &SE+7HXw
} |Zrkk>GW:
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publicint getPageSize(){ MW6KEiQ"
return pageSize; @ag*zl
} Pb-Ft=
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publicvoid setPageSize(int pageSize){ eEG]JH
this.pageSize = pageSize; \9t6#8
} +O,h<*y
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publicint getTotalCount(){ hPHrq{YZ
return totalCount; lm;G8IP`
} N>}2&'I
qxe%RYdA'j
publicvoid setTotalCount(int totalCount){ ep3iI77/
if(totalCount > 0){ 8fwM)DKS
this.totalCount = totalCount; T>;Kq;(9
int count = totalCount / gwepaW
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pageSize; H^no&$2`1
if(totalCount % pageSize > 0) 1"82JN|!
count++; zUhJr$N$
indexes = newint[count]; Xqac$%[3
for(int i = 0; i < count; i++){ >O{/%(9
indexes = pageSize * s *B-|
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i; nBVknyMFNF
} /:}z*a
}else{ wCb%{iowH
this.totalCount = 0; P00pSRQHD
} ^{W#ut>IN
} Nh[{B{k
+RO=a_AS
publicint[] getIndexes(){ 69v[*InSd
return indexes; Tcglt>tj"
} '\2lWR]ndd
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publicvoid setIndexes(int[] indexes){ H5N(MihT
this.indexes = indexes; ):_x
} j{nkus2
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publicint getStartIndex(){ Lu~e^Ul
return startIndex; 6L6 Lk
} z^f-MgWG
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publicvoid setStartIndex(int startIndex){ \4SFD3$&
if(totalCount <= 0) ^/Hj^4~_U
this.startIndex = 0; "*@iXJxv5
elseif(startIndex >= totalCount) b'N"?W^YQ
this.startIndex = indexes B%Yb+M&K
|yI?}zyR
[indexes.length - 1]; n^/,>7J
elseif(startIndex < 0) 2="C6
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this.startIndex = 0;
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else{ <EI'N0~KG
this.startIndex = indexes zYOPE 6E
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[startIndex / pageSize]; Ze$:-7Czl
} gzDb~UEoF
} @D"1}CW
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publicint getNextIndex(){ zck)D^,aO
int nextIndex = getStartIndex() + ?NI)3-l
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pageSize; ,)L.^<
if(nextIndex >= totalCount) $)@zlnU
return getStartIndex(); q@(N 38D
else "_)
return nextIndex; kX1hcAa
} @V :b Co
4
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publicint getPreviousIndex(){ JsPuxu_
int previousIndex = getStartIndex() - 8}\"LXRbo
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pageSize; _k+Bj.L
if(previousIndex < 0) u gfV'
return0; N7#GK]n%/}
else T
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return previousIndex; # |UrHK;
} E/GI:}YUy_
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} h}`<pq
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抽象业务类 Vr0RdO
java代码: alu`T
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/** :!A@B.E
* Created on 2005-7-12 i([A8C_A
*/ v^E5'M[A
package com.javaeye.common.business; RZ.5:v6
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import java.io.Serializable; Lq&xlW
j
import java.util.List; %Bo Jt-v
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import org.hibernate.Criteria; 0CN.gu
import org.hibernate.HibernateException; l;;:3:
import org.hibernate.Session; kdo)y(fn@
import org.hibernate.criterion.DetachedCriteria; WMC6dD_6e
import org.hibernate.criterion.Projections; }gn0bCJy
import IWQ8e$N
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org.springframework.orm.hibernate3.HibernateCallback; l:[=M:#p
import P~*fZ)\}F@
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org.springframework.orm.hibernate3.support.HibernateDaoS {oZ]1Qf_
=Vv{ td
upport; 2-CK:)n/#
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import com.javaeye.common.util.PaginationSupport; 2-6-kS)c
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public abstract class AbstractManager extends >9klh-f
HvngjP{>
HibernateDaoSupport {
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privateboolean cacheQueries = false; &V;a:
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privateString queryCacheRegion; M1i|qjb:l
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publicvoid setCacheQueries(boolean c2U>89LlZ
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cacheQueries){ t>[r88v
this.cacheQueries = cacheQueries; t Z%?vY~!
} Gg+>_b{S5T
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publicvoid setQueryCacheRegion(String N4:'X6u;
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queryCacheRegion){ qq`RfZjL
this.queryCacheRegion = )0Lq>6j9
'tbb"MEi4
queryCacheRegion; @.{
} u%pief
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publicvoid save(finalObject entity){ @FTi*$Ix
getHibernateTemplate().save(entity); ^WNJQg'
} |^F-.Z
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publicvoid persist(finalObject entity){ 1bBK1Uw
getHibernateTemplate().save(entity); nqBuC
} "jHN#}
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publicvoid update(finalObject entity){ Y[!a82MTzn
getHibernateTemplate().update(entity); =(ZGaZ}
} @I&"P:E0F;
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publicvoid delete(finalObject entity){ -)oBh
getHibernateTemplate().delete(entity); MjpJAV/84
} z+*Z<c5d
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publicObject load(finalClass entity, FT~^$)8=
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finalSerializable id){ G)&'8W F5o
return getHibernateTemplate().load {<kG{i/
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(entity, id); =@2V#X]M*
} K_QCYS.
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publicObject get(finalClass entity, !qlGt)G3
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finalSerializable id){ 9#<Og>t2y
return getHibernateTemplate().get yUO|3ONT
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(entity, id); F-^HN%
} BuTIJb+Q\
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publicList findAll(finalClass entity){ h
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return getHibernateTemplate().find("from hli10p$
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" + entity.getName()); {ah=i8$
} U*Qq5=dqD
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publicList findByNamedQuery(finalString N;'HR)
,:4DN&<
namedQuery){ pm]DxJ@
return getHibernateTemplate fm%RNAPvc
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().findByNamedQuery(namedQuery); 6
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} toqzS!&.v
^,lZ58
2
publicList findByNamedQuery(finalString query, _-]!;0EIV
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finalObject parameter){ q9Sz7_K
return getHibernateTemplate VONAw3k7!
O[)]dD&'
().findByNamedQuery(query, parameter); EWIc|b:
} =nx:GT3&[
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publicList findByNamedQuery(finalString query, zN+*R;Ds
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finalObject[] parameters){ oL'1Gm@X?
return getHibernateTemplate &4Con%YU[
pP* ~ =?
().findByNamedQuery(query, parameters); V.ji
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} IT`=\K/[4
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publicList find(finalString query){ &
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return getHibernateTemplate().find 6_<s=nTX
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(query); [z% ?MIT
} Y/,$Y]%g
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publicList find(finalString query, finalObject MJ*]fC3/
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parameter){ tB7K&ssi
return getHibernateTemplate().find ~sU?"V
%,,`N I{
(query, parameter); rjL?eTU"s
} a1G9wC:e
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public PaginationSupport findPageByCriteria =1*%>K
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(final DetachedCriteria detachedCriteria){ ?Z Rkn+;
return findPageByCriteria OyJsz]b} M
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); [Iw>|q<e
} ^r>f2 x
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public PaginationSupport findPageByCriteria N&fW9s}
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(final DetachedCriteria detachedCriteria, finalint N )zPxQ
U['JFLF
startIndex){ |
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return findPageByCriteria j?\$G.Y
gT(th9'+z
(detachedCriteria, PaginationSupport.PAGESIZE, JG@L5f
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startIndex); 9jO`gWxV8*
} &_9YLXtMi;
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public PaginationSupport findPageByCriteria [J)/Et
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(final DetachedCriteria detachedCriteria, finalint "H>r-cyh
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pageSize, E3S%s
finalint startIndex){ {gFAvMj#
return(PaginationSupport) d"B@c;dD
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getHibernateTemplate().execute(new HibernateCallback(){ j?:`-\w5
publicObject doInHibernate =U4f}W;
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(Session session)throws HibernateException { m$fQ `XzU
Criteria criteria = h@*lWi2K7
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detachedCriteria.getExecutableCriteria(session); {I0w`xe
int totalCount = 7hB#x]oQo
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((Integer) criteria.setProjection(Projections.rowCount (U|)xA]y!
U^%9
)4bj
()).uniqueResult()).intValue(); K;oV"KRK
criteria.setProjection j4;Du>obQ
wgY6D!Y
(null); ,~(|p`
List items = UT3bd,,
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criteria.setFirstResult(startIndex).setMaxResults A LXUaE.
pw@`}cM=
(pageSize).list(); gUl1CH&
PaginationSupport ps = 8
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new PaginationSupport(items, totalCount, pageSize, .iFViVZC
3 m6$YWO
startIndex); ?RHn @$g8M
return ps; M~uMY+>
} %/5 1o6a
}, true); P{?;T5ap6
} 7 0_}S*T
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public List findAllByCriteria(final w4UD/zO
Q| ?'(J+
DetachedCriteria detachedCriteria){ AcKU^T+
return(List) getHibernateTemplate >?z:2@Q)B
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().execute(new HibernateCallback(){ I?B,sl_w
publicObject doInHibernate ML=eL*}l
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(Session session)throws HibernateException { /hL\,x2
Criteria criteria = E, GN| l
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detachedCriteria.getExecutableCriteria(session); K4:
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return criteria.list(); =~&VdPZ
} 6ZcXS
}, true); 1RLym9JN
} u"`*DFjo*
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public int getCountByCriteria(final eeM?]J-
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DetachedCriteria detachedCriteria){ 5MR,UgT
Integer count = (Integer) V4|uas{0I:
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getHibernateTemplate().execute(new HibernateCallback(){ ^ *0'\/N&
publicObject doInHibernate )hBE11,PB
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(Session session)throws HibernateException { ?F_)-
Criteria criteria = f"dSr
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detachedCriteria.getExecutableCriteria(session); 0mTr-`s
return ]n;1x1'
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criteria.setProjection(Projections.rowCount Qs%B'9")
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()).uniqueResult(); rOcg+5
} Y]Vq\]m\
}, true); BRzfic:e
return count.intValue(); Z+4D.bA
} GSi>l,y'
} Ch19h8M
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用户在web层构造查询条件detachedCriteria,和可选的 pr&=n;_ n
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 *2e!M^K<
QI_4*
PaginationSupport的实例ps。 9t$]X>}
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ps.getItems()得到已分页好的结果集 H43MoC
ps.getIndexes()得到分页索引的数组 }Wh6zT)
ps.getTotalCount()得到总结果数 kXrlSaIc
ps.getStartIndex()当前分页索引 KOhA)
ps.getNextIndex()下一页索引 fuMJdAuY7d
ps.getPreviousIndex()上一页索引 /.1.MssQM
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 VIJ<``9[
8gy_Yj&{P
,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 [p;E~-S
(Pbg[AY
一下代码重构了。 p B;3bc
hA1-){aw3q
我把原本我的做法也提供出来供大家讨论吧: )"+2Z^1-
D5,P)[
首先,为了实现分页查询,我封装了一个Page类: EYX$pz(x;
java代码: bm% $86
jMNU ?m:
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/*Created on 2005-4-14*/ .iD*>M:W
package org.flyware.util.page; !\Xm!I8
T r0B[QF
/** 2L?!tBw?1
* @author Joa tptN6Isuh
* ({WyDu&=
*/ fw6UhG
publicclass Page { kOo~%kcQ'
\</b4iR)LT
/** imply if the page has previous page */ wV\gj~U;P
privateboolean hasPrePage; \p{5D`HY
]n."<qxeT
/** imply if the page has next page */ ?L&|Uw+
privateboolean hasNextPage; F#
T 07<
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/** the number of every page */ _j?e~w&0b
privateint everyPage; =L;] ;i
+l3=3
/** the total page number */ ~w8JH2O
privateint totalPage; OCZaQ33
YW u cvw&
/** the number of current page */ ,to+oSZE
privateint currentPage; M])dJ9&e
W@|6nPm
/** the begin index of the records by the current ^j-3av=
^WBuMCe
query */ ]BR,M4
privateint beginIndex; #Zrlp.M4
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y6]vl=^L
/** The default constructor */ Xp0F
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public Page(){ _uc
hU=
.{y
uo{u
} #9K-7je;j
C8z{XSo
/** construct the page by everyPage |2{wG4
* @param everyPage g=I8@m
* */ sc,Xw:YO
public Page(int everyPage){ W`c'=c
this.everyPage = everyPage; EkziAON
} pAT7)Ch
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/** The whole constructor */ r Tz$^a}/
public Page(boolean hasPrePage, boolean hasNextPage, 6{txm+U
)"pF R4
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int everyPage, int totalPage, l+V>]?j
int currentPage, int beginIndex){ ,G)r=$XU
this.hasPrePage = hasPrePage; YpqrZWvh
this.hasNextPage = hasNextPage; G;YrF)\
this.everyPage = everyPage; 8YbE`32
this.totalPage = totalPage; P-9<YN
this.currentPage = currentPage; MG.`
r{5
this.beginIndex = beginIndex; 55z]&5N
} Mxv;k%l|E|
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/** >rf'-X4n
* @return 5k.oW=
* Returns the beginIndex. HPZ}*m'
*/ %\:[ o
publicint getBeginIndex(){ i*Z"Me
return beginIndex; #?S^kM-0
} *=V~YF:Qb
5?]hd*8
/** pu2tY7Ja
* @param beginIndex kH
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* The beginIndex to set. ,Y/ g2
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*/ Hl{S]]z
publicvoid setBeginIndex(int beginIndex){ ~?K ~L~f5
this.beginIndex = beginIndex; &E.^jR~*
} YoBDvV":@
VHIOwzC
/** u>2
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* @return @$[?z9ck"
* Returns the currentPage. v|dBSX9k0
*/ ^")Q YE
publicint getCurrentPage(){ 2N: ,Q8~
return currentPage; 1H6<[iHW
} l`#4KCL(
um!J]N^
/** *Q?tl\E
* @param currentPage ]>=}*=
* The currentPage to set. 3G}x;Cp\D
*/ 5Co
publicvoid setCurrentPage(int currentPage){ /5(Yy}
this.currentPage = currentPage; ;f#v0W`5
} pNepC<rY
&"&Z
#llb
/** gG<~-8uQ
* @return a&/#X9/
* Returns the everyPage. <
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*/ <m)$K
publicint getEveryPage(){ "{@A5A
return everyPage; J:CXW%\ <q
} u0|8Tgf
?!A7rb/tj
/** z> Rsi
* @param everyPage w$zu~/qV2
* The everyPage to set. Dfg2`l
*/ Wh+{mvu#
publicvoid setEveryPage(int everyPage){ We$:&K0
this.everyPage = everyPage; ]zE;Tw.S
} $q6BP'7
.}t~'*D
/** EMwS1~3dD
* @return rI= v
* Returns the hasNextPage. _<k\FU
r
*/ D!{Y$;
publicboolean getHasNextPage(){ [ey:e6,T9
return hasNextPage; nKPYOY8^
} +giyX7BPJ
b LlKe50
/** U
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* @param hasNextPage 6t>.[Y"v
* The hasNextPage to set. Gw>^[dmt!
*/ EYtL_hNp}I
publicvoid setHasNextPage(boolean hasNextPage){ HG^B#yX
this.hasNextPage = hasNextPage; Wvbf"hq
} LPZF)@|`
0Vlk;fIh
/** R<\F:9
* @return G,?hp>lj
* Returns the hasPrePage. $Z.7zH
*/ H5DC[bZMb%
publicboolean getHasPrePage(){ ^T*? >%`
return hasPrePage; l)G^cSHF.3
} 7E!IF>`
S|SV$_
(
/** ?u{~>
* @param hasPrePage |v \_@09=
* The hasPrePage to set. AJh w
*/ 1n=lqn/
publicvoid setHasPrePage(boolean hasPrePage){ &~8oQC-eF
this.hasPrePage = hasPrePage; n!YKz"$
} hBS.a6u1'd
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/** =d".|k
* @return Returns the totalPage.
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* }Ga\wV
*/ oC<.=2]
publicint getTotalPage(){ 4lr(,nPRD
return totalPage; ^A!Qc=#z}
} aoTM
/ :
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/** 2;zb\d
* @param totalPage Z'4./
* The totalPage to set. 5*+!+V^?X
*/ C>-aIz!y
publicvoid setTotalPage(int totalPage){ k`So -e-
this.totalPage = totalPage; FKIw!m ~
} f-bVKHt
h}*/Ge]aM
} kO,zZF&
".W8)
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8cU}I4|
m+b):
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 y`\@N"Cf
B|R@5mjm
个PageUtil,负责对Page对象进行构造: s"0Y3x3
java代码: W?qmp|YD
0O9Ni='Tn
eIz<)-7:
/*Created on 2005-4-14*/ $K]m{
package org.flyware.util.page; :K-~fA%kt?
vK9E
import org.apache.commons.logging.Log; ePr&!Tz#
import org.apache.commons.logging.LogFactory; qT%FmX
&^#VN%{
/** ba[1wFmcL
* @author Joa 8.XoVW#
* zbk q
*/ UaWl6 Y&Vu
publicclass PageUtil { Km(n7Ah"
ht2\ y&si
privatestaticfinal Log logger = LogFactory.getLog ?)kG A$m#
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(PageUtil.class); f|B=_p80
d Vj_8>
/** kS_(wpA
* Use the origin page to create a new page Oy%''+g
* @param page h-G)o[MA
* @param totalRecords *1v[kWa?
* @return vgsJeV`}I
*/ 8zRP(+&W
publicstatic Page createPage(Page page, int }|g\ 8jq
zG ^$"f2
totalRecords){ \HKxh:F'
return createPage(page.getEveryPage(), .!f$
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U%<koD[,
page.getCurrentPage(), totalRecords); LcUh;=r}&
} E%rk[wI
)XvilCk1
/** r [4tPk
* the basic page utils not including exception Hea;?4Vg
_H j!2 '
handler Tk5W'p|6f
* @param everyPage aX5
z&r:{
* @param currentPage ~GL]wF2#
* @param totalRecords ,n3a
gkPO>
* @return page :I+Gu*0WD
*/ IOqwCD[
publicstatic Page createPage(int everyPage, int `< xn8h9p
b:tob0TB
currentPage, int totalRecords){ B56L1^7
everyPage = getEveryPage(everyPage); YVHm{A1b0
currentPage = getCurrentPage(currentPage); &e#~<Wm82
int beginIndex = getBeginIndex(everyPage, DXJ`oh
|}(`kW
currentPage); LUM@#3&
int totalPage = getTotalPage(everyPage, ^(f"v
e#7v
" @v <Bk
totalRecords); D-5VC9{
boolean hasNextPage = hasNextPage(currentPage, Gn ~6X-l
l'/R&`-n
totalPage); g*03{l#P
boolean hasPrePage = hasPrePage(currentPage); Z0Vl+
VGpWg rmHk
returnnew Page(hasPrePage, hasNextPage, 0n;<
ge&~R
everyPage, totalPage, #xX5,r0
currentPage, $a
]_w.@
0K`#>}W#X
beginIndex); KK iE@_z
} SYCEQ5
-
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privatestaticint getEveryPage(int everyPage){ /OLFcxEWh
return everyPage == 0 ? 10 : everyPage; lku[dQdk
} 6{n!Cb[e
VF?<{F
privatestaticint getCurrentPage(int currentPage){ ow_W%I=6
return currentPage == 0 ? 1 : currentPage; WST8SEzJ
} bdC8zDD
IsZHelg
privatestaticint getBeginIndex(int everyPage, int Xejo_SV&?
:.Jf0
currentPage){ NG "C&v
return(currentPage - 1) * everyPage; ="Ho%*@6
} i;/5Y'KZ
wO'TBP
privatestaticint getTotalPage(int everyPage, int oU056
3Z5D)zuc
totalRecords){ W+UfGk}A
int totalPage = 0; ^(vs.U^U<
Nl^;A><u
if(totalRecords % everyPage == 0) bCo7*<I4
totalPage = totalRecords / everyPage; t&H?\)!4
else e+~\+:[?
totalPage = totalRecords / everyPage + 1 ; GFeQ%l`7F
oW ::hB
return totalPage; 7
n8"/0kc:
} AK'[c+2[
uJzG|$;
privatestaticboolean hasPrePage(int currentPage){ l`oZ)?ur
return currentPage == 1 ? false : true; kD=WO4}
} ZA0mz 65
&J[:awQX
privatestaticboolean hasNextPage(int currentPage, fmU {
F*IzQ(#HW
int totalPage){
gbF+WE
return currentPage == totalPage || totalPage == #M9~L[nFS
U{2BVqM
0 ? false : true; 't:;irLW.
} 3{'Ne}5%I
A P)L:7w'e
NjVYLn<.r
} q!.byrod
zr-*$1eu
Cn,d?H
Gr*r=s
e>6y%v;
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 @$ne{2J3
'GNK "XA^
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 f.D?sH An
dq(uVW^&ae
做法如下: 0(eBZdRO
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 )(bW#-
\hTm)-FP
的信息,和一个结果集List: `7c~mypx
java代码: 7?#J~.d5
}tRm] w
LhA*F[6$M
/*Created on 2005-6-13*/ 3
}duG/
package com.adt.bo; {#ZlM
VLOO8N[o
import java.util.List; &Y!-%{e
|?!~{-o
import org.flyware.util.page.Page; F0GxH?
?^7t'`zk
/** ND'E8Ke pq
* @author Joa yQU{zY
*/ /NLui@|R
publicclass Result { G? ])o5
C].iCxn
private Page page; O8+7g+J=!
B;M?,<%FRU
private List content; VU#`oJ:{
B}n,b#,*
/** Hkk/xNP
* The default constructor lG9bLiFY
*/ 2a-w%
(K
public Result(){ qz+dmef
super(); };mA^xO]j
} t#V!8EpBg
ojafy}
/** h:W;^\J:-
* The constructor using fields )SaGH3~*C
* Q!o'}nA
* @param page O@tU.5*$5
* @param content O[\iE5+$
*/ D60aH!ft
public Result(Page page, List content){ FTX=Wyr
this.page = page; v]'ztFA
this.content = content; :yL] ;J
} l>2E (Y|
6o!!=}'E[
/** -Y1e8H ='
* @return Returns the content. `EEL1[:BR
*/ S{Kiy#ltWc
publicList getContent(){ -j+UMlkB
return content; e|NG"<
} #9B)Xx!g
yd^{tQi
/** ")_|69 VX
* @return Returns the page. J &o|QG
*/ zE336
public Page getPage(){ T] R|qlZ
return page; -0d0t!
}
H_B4
5<iV2Hx
/** [8.c8-lZ^
* @param content Qn^'
* The content to set. 6 +Sxr
*/ *]. 7dec/
public void setContent(List content){ G[B=>Cy
this.content = content; 8/DS:uM
}
jPC[_g
8&;UO{
/** @+;$jRwq
* @param page \@-@Y
* The page to set. ]O Z5fd
*/ G
!<Z.]
publicvoid setPage(Page page){ PUz*!9HC
this.page = page; /Y*WBTV'
} +cWLjPD/}
} `0rd26Qro
SIe="YG]<
zuP B6W ^
{.n"Z
> pgX^
2. 编写业务逻辑接口,并实现它(UserManager, B*qi_{Gp
'z
);
UserManagerImpl) 7t3X)Ah
java代码: h,QKd>4:CF
gwNq
x"
hrmut*<|
/*Created on 2005-7-15*/ -T!f,g3vW
package com.adt.service; "-y-iJ
UT>s5C
import net.sf.hibernate.HibernateException; zFfoqb#*g
t4{rb,
}W
import org.flyware.util.page.Page; ?xK8#
?m![Pg%
import com.adt.bo.Result; z,|r*\dw
YpQ7)_s?
/** z|fmrwkN'$
* @author Joa X(!Cfb8+5
*/ <wZQc
publicinterface UserManager { ~7Y+2FZ
J5*tJoCYS
public Result listUser(Page page)throws "rTQG6`
QFfK0X8cC
HibernateException; @*>@AFnf\Z
"b?v?V0%C
} c/Qt Ot
b`L%t:u{d
`(T,+T4C5k
n 9\
C2r
@95FN)TXZY
java代码: L}GC<D:
u?>B)PW
~+bv6qxg]\
/*Created on 2005-7-15*/ 1[kMOp
package com.adt.service.impl; Tskq)NU
0 - ><q
import java.util.List; ur*T%b9&
Zkx[[gzL
import net.sf.hibernate.HibernateException; g wz7krUTe
x2@U.r"zo
import org.flyware.util.page.Page; &P.4(1sC
import org.flyware.util.page.PageUtil; 79nG|Yj|\
np%\&CVhN
import com.adt.bo.Result; lJ+0P2@h*
import com.adt.dao.UserDAO; p7);uF^O%
import com.adt.exception.ObjectNotFoundException; BQBeo&n6
import com.adt.service.UserManager; .udv"?!z
>:zK?(qu,N
/** h\7fp.
* @author Joa @)-sTgn
*/ [v$0[IuY,
publicclass UserManagerImpl implements UserManager { !E,A7s
?gJOgsHJP
private UserDAO userDAO; bfA=3S"0
4VHqBQ4
/** !1n8vzs"c
* @param userDAO The userDAO to set. )>b.;
*/ OS4q5;1#
publicvoid setUserDAO(UserDAO userDAO){ \=+b}mKV
m
this.userDAO = userDAO; ZeUvyIG
} Au{<hQ =
DVah
/* (non-Javadoc) zS\E/.X2
* @see com.adt.service.UserManager#listUser 61/.K_%I.
U7doU' V/
(org.flyware.util.page.Page) |fxA|/s[<
*/ @o#!EfZyE
public Result listUser(Page page)throws S{FROC~1R
w^L ta
HibernateException, ObjectNotFoundException { @Ys!DScY,
int totalRecords = userDAO.getUserCount(); tniDF>Rb
if(totalRecords == 0) pWPIJ>2G:
throw new ObjectNotFoundException cC o`~7rE
JoRT&rkd
("userNotExist"); lY~4'8^
page = PageUtil.createPage(page, totalRecords); JT "B>y>
List users = userDAO.getUserByPage(page); -RO7
'm0
returnnew Result(page, users); nL$x|}XAcj
} K`/`|1
>H(i^z/c
} |+35y_i6
K=C!b?
>w-;Z>3Q@
[,K.*ZQi
QCH}-q)
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fLSXPvm
ZDD..j
询,接下来编写UserDAO的代码: pl5P2&k
3. UserDAO 和 UserDAOImpl:
B3H|+
java代码: Y4cYZS47
"6R
5+
yz-,)GB6
/*Created on 2005-7-15*/ a 4=N9X
package com.adt.dao; uKz,SqX
:N<.?%Kf
import java.util.List; &?uz`pv2
ot`%*
import org.flyware.util.page.Page; /0W9g
R*oXmuOsYA
import net.sf.hibernate.HibernateException; 21ppSN>
\S*$UE]uG
/** |y h\
* @author Joa P7 ]z
*/ i.xXb[M+
publicinterface UserDAO extends BaseDAO { I.Y['%8,5~
U9&k;`
publicList getUserByName(String name)throws kM'"4[,nz
zF@o2<cD@
HibernateException; 9U {y1}
/wxE1][.
publicint getUserCount()throws HibernateException; yMZHUd
nLwiCfe
publicList getUserByPage(Page page)throws Bd^"=+c4
X*g(q0N<S
HibernateException; W(25TbQ
Zes+/.sA}]
} ^9_UUzf\
l{:a1^[>y
(=16PYs
/w8"=6Vv~
D?~8za`5
java代码: uK("<u|
9'DtaTmGW
T#
lP!c
/*Created on 2005-7-15*/ R*zO
dxY
package com.adt.dao.impl; ExSO|g]%
R8-^RvG
import java.util.List; @ct+7v~
X 6lH|R
import org.flyware.util.page.Page; YB)3X[R+0
DY{cQb
import net.sf.hibernate.HibernateException; 2 $ !D* <
import net.sf.hibernate.Query; Sf/q2/r?6[
Jz:r7w{4eB
import com.adt.dao.UserDAO; `_5GG3@Ff
1|ZhPsD.}g
/** 659v\51*
* @author Joa LF?P>
1%-
*/ b@t5`Y-+K
public class UserDAOImpl extends BaseDAOHibernateImpl H@l}[hkP
dQgk.k
implements UserDAO { SQWafD
NQ|xM"MqD
/* (non-Javadoc) j2M+]Zp.
* @see com.adt.dao.UserDAO#getUserByName 1ndJ+H0H
}wwe}E-e
(java.lang.String) I\Glc=T*
*/ U>S`k6
publicList getUserByName(String name)throws I,ci >/+b
XM|%^ry
HibernateException { }:z5t,u6
String querySentence = "FROM user in class +m,!e*g
6+dn*_[Z6
com.adt.po.User WHERE user.name=:name"; !EF(*~r!9L
Query query = getSession().createQuery d"~(T:=r
{13!vS%5
(querySentence); IeF keE
query.setParameter("name", name); ] c}91
return query.list(); uXQ >WI@eF
} Di Or{)a
XTqm]
/* (non-Javadoc) F6S~$<
* @see com.adt.dao.UserDAO#getUserCount() U3#dT2U
*/ >O]s&34
publicint getUserCount()throws HibernateException { {.k)2{
int count = 0; $E(XjuS
String querySentence = "SELECT count(*) FROM MZ#T^Y
t7F.[uWD
user in class com.adt.po.User"; ,
fb(
WY
Query query = getSession().createQuery %*)2s,8
x:5dCI
(querySentence); |$hgT K[L
count = ((Integer)query.iterate().next 3gfimD$ _E
Sl~x$9`
()).intValue(); _MYx%Z
return count; QLbMPS
} 8&}~'4[b[$
qeaA&(|5
/* (non-Javadoc) 0H=9@
* @see com.adt.dao.UserDAO#getUserByPage [@{0o+.]'H
Q
e1oT)
(org.flyware.util.page.Page) +T_ p8W+j
*/ 'M'w,sID
publicList getUserByPage(Page page)throws +lp{#1q0
s3lJu/Xe{
HibernateException { f =_^>>.
String querySentence = "FROM user in class 17py).\
dc^Vc{26Z
com.adt.po.User"; D6=HYqdj
Query query = getSession().createQuery JmWR{du
{-*\w-~G
(querySentence); 5RA<Z.
query.setFirstResult(page.getBeginIndex()) ;9rTE|n
.setMaxResults(page.getEveryPage()); ~Q!~ eTw
return query.list(); 1
Nk1MGV
} O@`J_9
7,_-XV2
} ag]*DsBt
sC6r.@[u8t
ec?1c&E
z<QIuq
$y6rvQ
2>S
至此,一个完整的分页程序完成。前台的只需要调用 u&3EPu
j6X LyeG7
userManager.listUser(page)即可得到一个Page对象和结果集对象 y''0PSfb#
S1C^+Sla]
的综合体,而传入的参数page对象则可以由前台传入,如果用 U(A4v0T
~|=rwDBZ8l
webwork,甚至可以直接在配置文件中指定。 CveWl$T12
a#R%8)
下面给出一个webwork调用示例: (6#M9XL
java代码: E8;TLk4\
ho|8U
fB[\("+
/*Created on 2005-6-17*/ ! [q}BU4
package com.adt.action.user; .q0AoM
3#<'[TF00t
import java.util.List; ._K$0U!
(l;C%O7*
import org.apache.commons.logging.Log; z qO$
import org.apache.commons.logging.LogFactory; Z_jn27AC
import org.flyware.util.page.Page; :D^Y?
6o9sR)c
?
import com.adt.bo.Result; >EeAPO4
import com.adt.service.UserService; /\TlO.B=
import com.opensymphony.xwork.Action; X#Ak'%J
[M<{P5q
/** Yg|l?d"
* @author Joa afV
P-m4L
*/ v?%0~!
publicclass ListUser implementsAction{ 6BR\iZ
"?`JA7~g
privatestaticfinal Log logger = LogFactory.getLog `L+~&M
+0dQORo
(ListUser.class); j&
<tdORT
U"/yB8!W
private UserService userService; *+NZQjl'
g8rp|MOH
private Page page; % Mw' e/?
3a/[."W
u
privateList users; 4*YOFU}l
5_PWGaQa
/* ?L8&(&1@VD
* (non-Javadoc) K:Mujx:
* IsWcz+1n
* @see com.opensymphony.xwork.Action#execute() D8q3TyCj%
*/ V>1D1
publicString execute()throwsException{ Bmi:2} j
Result result = userService.listUser(page); DBLA% {05
page = result.getPage(); ze*&*csO
users = result.getContent(); d?Ia#K93G
return SUCCESS; |R[v@c`pn
} NW}>pb9
uDpf2(>s
/** Bm65W
* @return Returns the page. ]u\ `
*/ k,
$I59
public Page getPage(){ L`<T'3G
return page; 8=lHUn9l
} N8Rm})
4.,KEt'H
/** EX+={U|ua$
* @return Returns the users. 2r PcNh9
*/ s_S<gR
publicList getUsers(){ {bAWc.
return users; v9j4|w
} cq'}2pob
lM@<_=2
/** `<l/GwtAJ
* @param page n"^/UQ|#j
* The page to set. ]Ssw32yn
*/ el2*\(XT
publicvoid setPage(Page page){ t
1Ir4
this.page = page; U}A|]vi@
} u7<qaOzs?
Sleu#]-
/** *G2)@0
{
* @param users (>!]A6^L~
* The users to set. l|R<F;|
*/ N$=(1`zM=
publicvoid setUsers(List users){ ;~'cITL
this.users = users; 7G<KrKal
} I]uOMWZs
(<d&BV- "
/** 'S%} ?#J
* @param userService 7/p J6>
* The userService to set. 6b#:H~ <
*/ lRa
3v Ng
publicvoid setUserService(UserService userService){ RTPq8S"
this.userService = userService; Dr8WV\4@
} d'lr:=GQ
} 7\\~xSXh
ex@,F,u>o
6)uPM"cO
&6,Yjs:T m
xzMeKC`
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, \GbHS*\+
Q}=W>|aE.
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 s{1Deek=
,E/Y@sajn+
么只需要: |%2/I>o
java代码: ABq {<2iYN
qmue!Fv#g
; mo\ yW1
<?xml version="1.0"?> 5Sm 5jRr
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork [d^:
%0~wtZH_!
1.0//EN" "http://www.opensymphony.com/xwork/xwork- D_
Bx>G9
v0hfY
1.0.dtd"> :9!0Rm
\AtwO
<xwork> U Qi^udGFD
z|DA
_dG
<package name="user" extends="webwork- Y|0-m#1F#
q563,s
interceptors"> {xBjEhQm
'4^V4i
<!-- The default interceptor stack name OFQi&/
u7Y'3x,`
--> e`Zg7CaDd
<default-interceptor-ref Y)4Nydq
rlO%%Qn`
name="myDefaultWebStack"/> (/x@W`
Hdq/E>u
<action name="listUser" 5%Fn^u:
P8,{k
class="com.adt.action.user.ListUser"> 1$!RKqT
<param 0w[0%:R^
YqY6\mo
name="page.everyPage">10</param> U:P3Z3Y%
<result Tm:#"h\F
I_6` Z 0
name="success">/user/user_list.jsp</result> pv m'pu78
</action> 6U>jU[/
o4[2`mT
</package> #HnyE+tD
SJ[@fUxO)
</xwork> n 8OdRv
6pn@`UK
WGG)
mh&-
^? {kj{v
>ya-
vs0H^L
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 ma-Y'
pTX'5
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。 HlL@{<
BL5
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 x&fCe{5
33KPo0g7
?jn6Op
wCTR-pL^
HToN+z%w3H
我写的一个用于分页的类,用了泛型了,hoho /qq&'}TZP
ihBl",l&Hq
java代码: pnA]@FW
ty< tv|p
S5
nw
package com.intokr.util; &'yV:g3H
p vR& ~g
import java.util.List; Mjvso0zj
-Lf6]5$2'
/** v|RaB
* 用于分页的类<br> hic$13KuP
* 可以用于传递查询的结果也可以用于传送查询的参数<br> rnhf(K.{3
* \\G6c4fC
* @version 0.01 c3!|h1h/v
* @author cheng l/UG+7
*/ x0;}b-f
public class Paginator<E> { fG$.DvJuK
privateint count = 0; // 总记录数 {uM{5GSL
privateint p = 1; // 页编号 R"t$N@ZFb
privateint num = 20; // 每页的记录数 !>@V#I
privateList<E> results = null; // 结果 u
R%R]X
Lpbn@y26<
/** 7%}3Ghc%
* 结果总数 &q}@[
)V4
*/ 2y7q
x1$C
publicint getCount(){ [}>6n72gNh
return count; :::f,aCAu
} j<P%Uy+
:RO:k|g
publicvoid setCount(int count){ >,Bu^] C
this.count = count; <T/L.>p4
} L"IHyUW
QIV~)`;
/** '^(v8lCu
* 本结果所在的页码,从1开始 ye7&y4v+
* n4&j<zAV{
* @return Returns the pageNo. 1p<?S}zg@
*/ 9k^=m)yS'
publicint getP(){ 64>[pZF8
return p; 4H?Ma|,
} y"-{6{3
3}1+"? s
/** SfFR
* if(p<=0) p=1 ~ A|*]0,
* j77}{5@p
* @param p ^ED>{UiNI
*/ ^Jc0c)*
publicvoid setP(int p){ 3'e 4{
if(p <= 0) #}yFHM?i
p = 1; eSBf;lr=
this.p = p; ]~Qk g+>'&
} be#"517
@}!$NI8
/** :{Z^ _;Tf
* 每页记录数量 {/!Gh\i
*/ !I/kz }N@
publicint getNum(){ N|vJrye
return num; Jz0S2&
} o:\a
B[X6AQj}d
/** +[[gU;U"v
* if(num<1) num=1
H,~In2Z
*/ Sd6^%YB
publicvoid setNum(int num){ rep"xV&|>o
if(num < 1) AR3=G>hO,
num = 1; r= aQS5
this.num = num; 7Z3qaXPH
} dD<kNa}2
}!Lr!eALr
/** \c}r6xOr
* 获得总页数 59 Y=VS
*/ .&.CbE8K[
publicint getPageNum(){ x=N;>
return(count - 1) / num + 1; cA2]VL.r>C
} EtGr&\,
X5[sw;rk
/** B ;$8<
* 获得本页的开始编号,为 (p-1)*num+1 \YS\*'F
*/ `<~P>
publicint getStart(){ ,u2<()`8D
return(p - 1) * num + 1; 1Tr=*b %f
} L 3@wdC~0
>,vuC4v-
/** 6si-IJ
* @return Returns the results. C\D4C]/8
*/ V485Yn!$(
publicList<E> getResults(){ 0in6z
return results; u*`GIRfWT
} DlI|~
$@;[K\
public void setResults(List<E> results){ B,T.bgp\
this.results = results; %C<eR_
} bmpB$@
Cj9Tj'0@I+
public String toString(){ {o`5&EoM
StringBuilder buff = new StringBuilder HfPeR8I%i
7F\g3^z9`
(); $h9!"f[|j
buff.append("{"); w"|c;E1;_
buff.append("count:").append(count); +
aFjtb
buff.append(",p:").append(p); _P:P5H8
buff.append(",nump:").append(num); Xy+|D#b
buff.append(",results:").append WAbhBA
ntejFy9_
(results); u 36;;z
buff.append("}"); 0
CS_-
return buff.toString(); j;.&+.
} <0m;|Ai'W
IYPLitT
} sJWwkR
76/%Py|
FCPbp!q6