Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 D=Ia$O0.
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 gS{hfDpk,h
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 vF
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 Ilt!O^
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分页支持类: aC$-riP,?'
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java代码: M"XILNV-~
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package com.javaeye.common.util; o8<0#W@S
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import java.util.List; $y%X#:eLJ
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publicclass PaginationSupport { d_t>
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publicfinalstaticint PAGESIZE = 30; 8w,+Y]X<P[
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privateint pageSize = PAGESIZE; =f48[=
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privateList items; 7TDt2:;]
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privateint totalCount; qKt*<KGeY
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privateint[] indexes = newint[0]; {@1;kG
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privateint startIndex = 0; nK!yu?mS
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public PaginationSupport(List items, int @=i-*U
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totalCount){ R_DstpsT
setPageSize(PAGESIZE); B=ckRWq
setTotalCount(totalCount); cd&^ vQL8
setItems(items); z (1zth
setStartIndex(0); ;+-@AYl
} kdgU1T@y.
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public PaginationSupport(List items, int EWb'#+BP
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totalCount, int startIndex){ :.VI*X:aQh
setPageSize(PAGESIZE); |2L|Zp&
setTotalCount(totalCount); O c,E\~
setItems(items); !g`^<y!
setStartIndex(startIndex); l+ ,p=
} 61aU~w11a
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public PaginationSupport(List items, int mp'Z.4
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totalCount, int pageSize, int startIndex){ =00c1v
setPageSize(pageSize); KD<smwXjG
setTotalCount(totalCount); 9 HiH6f^5
setItems(items); cD%_+@GaU
setStartIndex(startIndex); ^cz4nW<
} CD!Aa
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publicList getItems(){ 5V $H?MW>
return items; |&oTxx$S
} >eC>sTPQ{
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publicvoid setItems(List items){ &E?TR
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this.items = items; WR.>?IG2E
} u\y$<
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publicint getPageSize(){ 3|0wD:Dy
return pageSize; QomihQnc
} c:[8ng 2v
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publicvoid setPageSize(int pageSize){ n1Wo<$#
this.pageSize = pageSize; /prR;'ks
} si,)!%b
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publicint getTotalCount(){ <r1/& RW,
return totalCount; `9Rj;^NJ
} hh[@q*C
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publicvoid setTotalCount(int totalCount){ %HD0N&
if(totalCount > 0){ r
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this.totalCount = totalCount; *}'3|e4w}
int count = totalCount / }Pm;xHnf&
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pageSize; _u9bZ'
if(totalCount % pageSize > 0) _B?Hw[cc
count++; =x@v{cP
indexes = newint[count]; GboZ T68
for(int i = 0; i < count; i++){ 0B]c`$"aD
indexes = pageSize * aT~=<rEDy
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i; ILIv43QKM(
} 0<)Ep~!
}else{ YM,UM>
this.totalCount = 0; n#S?fsQN
} !q1XyQX
} i.0d>G><@
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publicint[] getIndexes(){ zmhAeblA
return indexes; %x8vvcO^t
} pN{XGkX.
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publicvoid setIndexes(int[] indexes){ ]zz%gZz
this.indexes = indexes; }\QXPU{UVd
} tN;^{O-(V
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publicint getStartIndex(){ 0E7h+]bh|
return startIndex; @o6!
} w19OOD
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publicvoid setStartIndex(int startIndex){ gNC'kCx0c
if(totalCount <= 0) r_MP[]f|0
this.startIndex = 0; EX@Cf!GjN
elseif(startIndex >= totalCount) F$S/zh$)0
this.startIndex = indexes o QR?H
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[indexes.length - 1]; Rl'xEtaN
elseif(startIndex < 0) JyePI:B&)j
this.startIndex = 0; #n+sbx5~7
else{ lNMJcl3
this.startIndex = indexes p.5 *`, )
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[startIndex / pageSize]; *,
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} 3}B-n!|*
} AD>/#Ul
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publicint getNextIndex(){ Lr Kx
int nextIndex = getStartIndex() + orFB*{/Z
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pageSize; EcPvE=^c
if(nextIndex >= totalCount) GS*_m4.Ry6
return getStartIndex(); iZ0.rcQj'o
else _)~|Z~
return nextIndex; !lKDNQ8>["
} d>/4z#R}-
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publicint getPreviousIndex(){ 7'5/T]Z
int previousIndex = getStartIndex() - xM>dv5<E
2|`~3B)#
pageSize; M#yUdl7d
if(previousIndex < 0) NM1TFs2Y*
return0; ]@qD4:
else S;BMM8U
return previousIndex; 17VNw/Y
} {h;i x
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} K,*If Hi6[
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抽象业务类 ik0w\*
java代码: )' 2vUt`_7
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/** ^Cg@'R9
* Created on 2005-7-12 V{0 V/Nv
*/ * =O@D2g0
package com.javaeye.common.business; i{PX=
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import java.io.Serializable; bre6SP@
import java.util.List; [oH,FSuO!2
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import org.hibernate.Criteria; 98WJ"f_ #
import org.hibernate.HibernateException; b$FXRR\G
import org.hibernate.Session; ||?wRMV
import org.hibernate.criterion.DetachedCriteria; qxD<mZ@-R0
import org.hibernate.criterion.Projections; St1>J.k_
import xX])IZD
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org.springframework.orm.hibernate3.HibernateCallback; ix}*whW=U
import LZu_-I
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org.springframework.orm.hibernate3.support.HibernateDaoS yDw^xGws
#/pZ#ny
upport; /XW,H0pR
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import com.javaeye.common.util.PaginationSupport; &nZ.$UK<
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public abstract class AbstractManager extends 9$'Edi=6
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HibernateDaoSupport { FkT% -I
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privateboolean cacheQueries = false; ~
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privateString queryCacheRegion; }(XvI^K[^
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publicvoid setCacheQueries(boolean 8JAT2a61ur
) uyh
cacheQueries){ +NEP*mk
this.cacheQueries = cacheQueries; yQ8H-a.
} ,@ Cru=
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publicvoid setQueryCacheRegion(String ^q$vyY
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queryCacheRegion){ (jYs_8;
this.queryCacheRegion = Dl/_jM
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queryCacheRegion; osX23T~-
} ikRIL2Y
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publicvoid save(finalObject entity){ 6YU2
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getHibernateTemplate().save(entity); [%nG_np
} ddHIP`wb
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publicvoid persist(finalObject entity){ MgMLfgt"V
getHibernateTemplate().save(entity); v981nJ>w,
} L}a3!33)C
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publicvoid update(finalObject entity){ -{b1&
getHibernateTemplate().update(entity); @7^#_772
} c[y=K)<Z
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publicvoid delete(finalObject entity){ X)f"`$
getHibernateTemplate().delete(entity); Z#MODf0H@
} g&E_|}u4
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publicObject load(finalClass entity, dju&Ku
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finalSerializable id){ o"1us75P
return getHibernateTemplate().load #=.h:_9
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(entity, id); ,m b3H
} "^D6%I#T
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publicObject get(finalClass entity, tl^[MLQa
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finalSerializable id){ [sk"2
return getHibernateTemplate().get _gGy(`
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(entity, id); L2h+[f
} 99:L#0!.W
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publicList findAll(finalClass entity){ ^c7L!F
return getHibernateTemplate().find("from ]Ojt3)fB
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" + entity.getName()); 0?h .X=G
} (_08?cN
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publicList findByNamedQuery(finalString }I`|*6Up
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namedQuery){ Q8~pIv
return getHibernateTemplate q%vUEQLBp
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().findByNamedQuery(namedQuery); H5I#/j
} zXC In
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publicList findByNamedQuery(finalString query, nz',Zm},
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finalObject parameter){ M#>GU<4"
return getHibernateTemplate } R/
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().findByNamedQuery(query, parameter); yN o8R[M
} UiEB?X]-l'
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publicList findByNamedQuery(finalString query, F3'X
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finalObject[] parameters){ *3K"Kc2
return getHibernateTemplate #?=cg]v_
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().findByNamedQuery(query, parameters); ]x G4T>S
} u~kwNN9t3
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publicList find(finalString query){ ~z}au"k
return getHibernateTemplate().find !T{g& f
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(query); <<1oc{i
} =KZ4:d5
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publicList find(finalString query, finalObject u@EM,o
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parameter){ !T~d5^l!
return getHibernateTemplate().find %ze1ZWO{
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(query, parameter); "p{'984r<
} >cNXB7]E>
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public PaginationSupport findPageByCriteria v^pP&
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(final DetachedCriteria detachedCriteria){ Q ?t
return findPageByCriteria PpRO7(<cD
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); "/?qT;<$)
} =R.9"7~2x
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public PaginationSupport findPageByCriteria <yPHdbF
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(final DetachedCriteria detachedCriteria, finalint af(JoX*U
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startIndex){ E3skC%}
return findPageByCriteria J#DcT@
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(detachedCriteria, PaginationSupport.PAGESIZE, Ekme62Q>u
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startIndex); CJixK>Y^
} ZD%_PgiT
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public PaginationSupport findPageByCriteria gj,J3x4TK/
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(final DetachedCriteria detachedCriteria, finalint Td1ba ^J
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pageSize, Z3>xpw G
finalint startIndex){ ~+egu89'TU
return(PaginationSupport) jYX9;C;J
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getHibernateTemplate().execute(new HibernateCallback(){ 5I1J)K;
publicObject doInHibernate je4&'vyU
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(Session session)throws HibernateException { A9Wqz"[
Criteria criteria = vfUfrk@D~
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detachedCriteria.getExecutableCriteria(session); s;7qNwYO
int totalCount = %*c|[7Z~V
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((Integer) criteria.setProjection(Projections.rowCount /^3oq]
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()).uniqueResult()).intValue(); (mIJI,[xn
criteria.setProjection LIC~Kehi
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(null); G5#}Ed4
List items = )?&kQ^@v
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criteria.setFirstResult(startIndex).setMaxResults qmeml_(W
,Kf8T9z`
(pageSize).list(); -wQ^oOJ
PaginationSupport ps = #S%Y;ilq
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new PaginationSupport(items, totalCount, pageSize, 4t
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startIndex); _G[I2]
return ps; *;e@t4
} ;c-
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}, true); pJIE@Q|hi
} ,&&M|,NQ&s
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public List findAllByCriteria(final V<2fPDZ
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DetachedCriteria detachedCriteria){ CQzjCRS
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return(List) getHibernateTemplate Wt9iL
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().execute(new HibernateCallback(){ qD;v/,?
publicObject doInHibernate ,r 2VP\hLh
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(Session session)throws HibernateException { )s<WG}
Criteria criteria = $7n#\h
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detachedCriteria.getExecutableCriteria(session); 20l_ay
return criteria.list(); CLY6 YB' R
} "Z 2Tc)
}, true); Cld<D5\|f+
} Bf:tal6 -M
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public int getCountByCriteria(final Wda\a.bXT
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DetachedCriteria detachedCriteria){ vDW&pF_eI>
Integer count = (Integer) 4l
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getHibernateTemplate().execute(new HibernateCallback(){ H*{k4
publicObject doInHibernate
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(Session session)throws HibernateException { Q6.*"`
Criteria criteria = qTTn51
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detachedCriteria.getExecutableCriteria(session); PG6L]o^
return 7mn,{2
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criteria.setProjection(Projections.rowCount +t>*l>[
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()).uniqueResult(); n4WSV
} YO(:32S
}, true); p584)"[*t
return count.intValue(); P#[IUXtT
} 4Hml.|$
} OgKWgvy
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用户在web层构造查询条件detachedCriteria,和可选的 z [qdmx^
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 (F,(]71Z+
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PaginationSupport的实例ps。 p;qRm}
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ps.getItems()得到已分页好的结果集 m3xz=9Ve
ps.getIndexes()得到分页索引的数组 66~e~F}z
ps.getTotalCount()得到总结果数 AZxrJ2G
ps.getStartIndex()当前分页索引 H_?;h-Y]
ps.getNextIndex()下一页索引 1UW s_|X!
ps.getPreviousIndex()上一页索引 W>Mse[6`c
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 m\6SG' X
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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 m x3}m?WQ
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一下代码重构了。 oMh~5
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我把原本我的做法也提供出来供大家讨论吧: g|ql 5jW
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首先,为了实现分页查询,我封装了一个Page类: YO@hE>
java代码: n 5~=qQK2
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/*Created on 2005-4-14*/ gf0PMc3l
package org.flyware.util.page; x1Nme%%&
,^.S0;D,Z
/** s8t f@H4r
* @author Joa 5R,la\!bQ
* h`?y2?O
*/ Hs[}l_gYn
publicclass Page { GhqgRzX
*-9# /Cp
/** imply if the page has previous page */ T$H2'tK|
privateboolean hasPrePage; tgO+*q5B
PSW#^o
/** imply if the page has next page */ R'G'&H{N
privateboolean hasNextPage; `aO.=:O_
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/** the number of every page */ X$BXT
privateint everyPage; `Uzs+k-]
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/** the total page number */ Ab*]dn`z
privateint totalPage; UG6M9
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/** the number of current page */ oz%h)#;
privateint currentPage; n<{aPLQ
dav vI$TA
/** the begin index of the records by the current -&trk
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query */ z8b
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privateint beginIndex; +``>,O6
q z=yMIy=
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/** The default constructor */ U8YO0}_z
public Page(){ Nt HbwU,
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} Qqp)@uM^
PT mf
/** construct the page by everyPage > P(eW7RL
* @param everyPage :OHSxb>[
* */ - dl}_
public Page(int everyPage){ 0[lS(K
this.everyPage = everyPage; ?^U c=
} BApa^j\?
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/** The whole constructor */ #xlZU
public Page(boolean hasPrePage, boolean hasNextPage, /[0F6
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int everyPage, int totalPage, O-Dc[t%
int currentPage, int beginIndex){ #De(*&y2
this.hasPrePage = hasPrePage; K~USK?Q%
this.hasNextPage = hasNextPage; 77``8,
this.everyPage = everyPage; {&uT3*V1
this.totalPage = totalPage; %Hh3u$Y,
this.currentPage = currentPage; o5>/}wIf
this.beginIndex = beginIndex; /n(9&'H<
} -=}b;Kf-
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/** Bgf=\7;5
* @return mLJDxh'B
* Returns the beginIndex. @Eo4U]-
*/ $;y1Qiel
publicint getBeginIndex(){ ~fBex_.o*
return beginIndex; j13riI3A
} Ex6o=D2
@2u#93Y
/** D{>\-]\
* @param beginIndex N50fL
* The beginIndex to set. L+73aN
*/ &T7cH>E'K^
publicvoid setBeginIndex(int beginIndex){ {ZG:M}ieN
this.beginIndex = beginIndex; iNXFk4
} (X*9w##x(
E&'#=K[
/** F% }7cm2
* @return \Y9I~8\gB
* Returns the currentPage. goB;EWz
*/ gd
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publicint getCurrentPage(){
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return currentPage; _1P`]+K\D$
} PzLJ/QER
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/** C*a,<`
* @param currentPage G&jZ\IV
* The currentPage to set. a/34WFC
*/ 5.dl>,
publicvoid setCurrentPage(int currentPage){ KhrFg1|
this.currentPage = currentPage; cg{Gc]'1#
} TQ?#PRB
\ p3v#0R{
/** h<)yJh
* @return )&Mq,@
* Returns the everyPage. ]9s\_A9
*/ [-Cu4mff
publicint getEveryPage(){ :b5XKv^
return everyPage; W]zwghxH
} @*SA$9/l
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/** z#RuwB+
* @param everyPage 2qlIy
* The everyPage to set. {a.
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*/ {gw[%[ZM
publicvoid setEveryPage(int everyPage){ pD[pTMG@$
this.everyPage = everyPage; QhsVIta
} # v+;:
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/** -qfnUh
* @return $,@JYLC2
* Returns the hasNextPage. y`6\L$c
*/ Gp8psH
publicboolean getHasNextPage(){ fQO
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return hasNextPage; Tv1]v.
} ;5N41_hG
^;4YZwW5w
/** a5)JkC
* @param hasNextPage 1U'ZVJ5bpK
* The hasNextPage to set. fq=:h\\G
*/ e+{BJN
vz
publicvoid setHasNextPage(boolean hasNextPage){ 0X#+#[W
this.hasNextPage = hasNextPage; 6m@0;Ht
} ]q&tQJ/Fa
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/** SwX@I6huM
* @return n7S;
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* Returns the hasPrePage. djfU:$!j&
*/ >9MS"t
publicboolean getHasPrePage(){ I3PQdAs~&h
return hasPrePage; *x!LKIpv
} ?^. Pt
8 ip^]
/** x%pRDytA
* @param hasPrePage ,WGc7NN`
* The hasPrePage to set. %0zS
*/ 'gCZ'edM
publicvoid setHasPrePage(boolean hasPrePage){ Wt:~S/l
this.hasPrePage = hasPrePage; +<{m45
} %i595Ij-]
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/** ; [FLT:$
* @return Returns the totalPage. 03Ukw/D&
* h\FwgkJP
*/ ~?d>fR:X
publicint getTotalPage(){ ;Yv14{T!
return totalPage; hJLT!33:
} Qh8C,"a
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/**
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* @param totalPage ,Y-S(
* The totalPage to set. [4: Yi{>
*/ Wj tft%
publicvoid setTotalPage(int totalPage){ 4kh8W~i;/
this.totalPage = totalPage; =+\$e1Mb*
} O+b6lg)q
AOAO8%|I
} j_V/GnEQ
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]=Pu\eE
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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 @k9Pz<ub
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个PageUtil,负责对Page对象进行构造: -K^41W71
java代码: tgB=vIw?3
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/*Created on 2005-4-14*/ =Epq%,4nG
package org.flyware.util.page; hkF^?AJ
D J_DonO]
import org.apache.commons.logging.Log; a'A s
import org.apache.commons.logging.LogFactory; JnHNkCaU
c=aO5(i0
/** xl,ryc3J
* @author Joa lQ$+JX;n(y
* 1$(
*/ yquAr$L!
publicclass PageUtil { 0
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privatestaticfinal Log logger = LogFactory.getLog }lO
}x
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(PageUtil.class); |]tZ hI"3<
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/** ,J&9kYz
* Use the origin page to create a new page x`L+7,&n
* @param page zR/IqW.`9
* @param totalRecords R\y'_S=#a
* @return O5OXw]
*/ }hq^+fC?
publicstatic Page createPage(Page page, int #g{Mne
v2=/[E@
totalRecords){ ;W6-i2?
return createPage(page.getEveryPage(), Vd<K4Tk
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page.getCurrentPage(), totalRecords); 9rS,?
} z<h|#@\
y!hi"!
/** LuL$v+`
* the basic page utils not including exception DJ|BM+
*m&%vj.Kc
handler > Y]_K
* @param everyPage
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* @param currentPage X Ny
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* @param totalRecords 1a*6ZGk.
* @return page kC31$jMC3!
*/ H:{?3gk.P3
publicstatic Page createPage(int everyPage, int 0R4akLW0
&~ y{'zoL
currentPage, int totalRecords){ N6q5`Ry
everyPage = getEveryPage(everyPage); {#9,j]<
currentPage = getCurrentPage(currentPage); qy&\Xgn;GA
int beginIndex = getBeginIndex(everyPage, J'Gm7h{
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currentPage); xU:4Y0y8
int totalPage = getTotalPage(everyPage, `0z/BCNB
B.RRdK+:
totalRecords); y;r"+bS8
boolean hasNextPage = hasNextPage(currentPage, 9t0Cj/w}
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totalPage); :cdQ(O.m
boolean hasPrePage = hasPrePage(currentPage); ~b#OFnyG
PT05DH
returnnew Page(hasPrePage, hasNextPage, B\/7^{i5
everyPage, totalPage, 1OP"5f
currentPage, yf?W^{^|
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beginIndex); ]!J<,f7W
} ki3 HcV
LyV#j>gD
privatestaticint getEveryPage(int everyPage){ *F|+2?a:$
return everyPage == 0 ? 10 : everyPage; RAwk7F3qn
} nzWQQra|?
sjb-Me?
privatestaticint getCurrentPage(int currentPage){ VfRs[3Q
return currentPage == 0 ? 1 : currentPage; 3A d*,>!
} D$$3fN.iEL
PLdf_/]-
privatestaticint getBeginIndex(int everyPage, int zuMO1s
@.1Qs`pt
currentPage){ :Fnzi0b
return(currentPage - 1) * everyPage; BvQUn@ XE
} *w|iu^G
P8IRH#ED
privatestaticint getTotalPage(int everyPage, int F^]aC98]1
-F1P28<?
totalRecords){ 0$l&i=L
int totalPage = 0; i(P>Y2s
M/l95fp
if(totalRecords % everyPage == 0) hg4J2m
totalPage = totalRecords / everyPage; V_lGj
else jceHKl
totalPage = totalRecords / everyPage + 1 ; L\YZT|
K(
%UBPoq
return totalPage; PF`:1;PU
} m|mG;8}pI
hwp/jO:7\
privatestaticboolean hasPrePage(int currentPage){ "h$D7 mL
return currentPage == 1 ? false : true; xY+A]Up|w
} _Qg{ ;
aoK4Du{
privatestaticboolean hasNextPage(int currentPage, Txu>/1N,
`BpCRKTG
int totalPage){ RW)k_#%=
return currentPage == totalPage || totalPage == [?|5oaK
C`pan /t
0 ? false : true; =O,e97
} 9!cW
.jCk#@+
e_^KI
} t9]r
sZT VM9<)
il7!}
z30= ay1
f!(cD80
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。 ?o@E1:aA
5uzpTNAMM1
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 <9T
[yg
h ;jsH!
做法如下: oR7 7`
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 u$\Tg3du2
~O8]3+U
的信息,和一个结果集List: y^3,X_0
java代码: eZ[#+0J
iKY-;YK
jD<9=B(g
/*Created on 2005-6-13*/ :ECw
\_"0$
package com.adt.bo; C>M6&=
6mX: =Q
import java.util.List; 8XgVY9]Qm
c'SM>7L
import org.flyware.util.page.Page; \/pVcR
N0=b[%g;n
/** ?fm2qrV@fp
* @author Joa \#HL`R"
*/ N#mK7|\c?:
publicclass Result { dfnX!C~6 \
f7K8m|
private Page page; omr:C8T>
-B",&yTV
private List content; XPrY`,kN
Fv<]mu
/** Gl=@>Dc%
* The default constructor &MBOAHhze
*/ f.sPE8#3=
public Result(){ 0GF%~6
super(); s8C:QC
} ^BQ>vI'.4
N <ja6Ac
/** iFY]0@yt
* The constructor using fields H)-L%l|9
* (gFQK[
* @param page ;H`=):U
* @param content TZ)(ZKX*R
*/ l@(t^68OD
public Result(Page page, List content){ 1i ?gvzrq
this.page = page; zaQ$ Ht
this.content = content; 3~#Z E;>#
} 6="M0%
"~B~{ _<j
/** ^Jc$BMaVg
* @return Returns the content. &?&'"c{;m
*/ MAl{66
publicList getContent(){ g4?Q.'dZr
return content; mOABZ#+Fk
} "87O4
#$
a>#d=.
/** (v9!g#
* @return Returns the page. 0q-0zXlSL
*/ ZK W@pW]U
public Page getPage(){ }//8$Z<(
return page; H!Fr("6}
} u66TrYS tG
56/.*qa
/** N^)<)?
* @param content 7/$nA<qM
* The content to set. ot&j HS'
*/ ;))[P_$zB
public void setContent(List content){ :T8u?@.
this.content = content; hlYS=cgY=
} Ih9O Rp7
rcD.P?"
/** eA;j/&qH
* @param page iPR!JX
_
* The page to set. :Q0?ub]
*/ (Q*2dd>
publicvoid setPage(Page page){ p7?CeyZ-V
this.page = page; k:&?$
} NXC~#oG
} ^Y1AeJ$L
eP-R""uPw
r? 6Z1
R]V~IDs
RBMMXJj
2. 编写业务逻辑接口,并实现它(UserManager, -;W\f<q]
G~Q*:m
UserManagerImpl) 8Iqk%n~(
java代码: w>1l@%Uo
+?J_6Mo@X
, 4h!"c
/*Created on 2005-7-15*/ 8VBkI Ygb
package com.adt.service; v)v{QNQp^
a!SR"3 k
import net.sf.hibernate.HibernateException; KBUAdpU8
83p$!8]u
import org.flyware.util.page.Page; s~IA},F,\
-Ihn<<uE?
import com.adt.bo.Result; ~7)rKHau
mYsuNTx!.
/** {!:|.!-u
* @author Joa P %U9S
*/ 6w:g77SH)%
publicinterface UserManager { wnZ*k(
Xm0&U?dZB
public Result listUser(Page page)throws oK(W)[u
N'Z_6A*-
HibernateException; XQ+-+CD
\!' {-J
} O #uaGziFf
OmoplJ+
pE YrmC
lL(}dbT~N
lhW#IiX
java代码: R+@sHsZ@
:*w:eKk
`,8R~-GPD
/*Created on 2005-7-15*/ p0:&7,+a,
package com.adt.service.impl; 4u{E D(
eF gb6dSh
import java.util.List; 0YsN82IDD
Xoa<r9
import net.sf.hibernate.HibernateException; qNuv?.7
$O8EiC!f6
import org.flyware.util.page.Page; h\: tUEg#J
import org.flyware.util.page.PageUtil; /hA}9+/
=c5 /cpZ^
import com.adt.bo.Result; Hi4@!]
import com.adt.dao.UserDAO; ADwwiq#E
import com.adt.exception.ObjectNotFoundException; p1`'1`.3
import com.adt.service.UserManager; g en3"\Og{
7p"~:1hU
/** 6m;wO r
* @author Joa
m%[2x#
*/ DlQ[}5STF
publicclass UserManagerImpl implements UserManager { C>(M+qXL+
*Tlws
private UserDAO userDAO; /n<Ncf
9O0
/** j{Qbzczy,
* @param userDAO The userDAO to set. &&QDEDszp
*/ hnfrnYH
publicvoid setUserDAO(UserDAO userDAO){ QeOt;{_|
this.userDAO = userDAO; ah&plaVzC
} "351s3ff
]aMa*fF
/* (non-Javadoc) ~]t2?SqNm
* @see com.adt.service.UserManager#listUser yI)RGOV
'=G<)z@k
(org.flyware.util.page.Page) ~)\1g0
*/ *7D$;?"
public Result listUser(Page page)throws uvK%d\d
]P ?#lO6
HibernateException, ObjectNotFoundException { {u[K
^G
int totalRecords = userDAO.getUserCount(); _R!!4Hp<Q
if(totalRecords == 0) .AQ3zpy5B
throw new ObjectNotFoundException uhN(`E@
l.W 1$g
("userNotExist"); x.4)p6
page = PageUtil.createPage(page, totalRecords); `
a<|CcUGU
List users = userDAO.getUserByPage(page); @0@'6J04
returnnew Result(page, users); URzE+8m^
} fN? Lz%z3
v.8S
V]
} ]\b1~ki!F
vEee/+1?
A"T. nqB^y
#}]il0d
3E2.v5*
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fB ,!|u
Tk@g9\6O9
询,接下来编写UserDAO的代码: sCf(h
3. UserDAO 和 UserDAOImpl: 8@C|exAD`
java代码: gt~2Br4
`LHfAXKN
4sD:J-c
/*Created on 2005-7-15*/ +M%2m3.Jo
package com.adt.dao; !v;_@iW3e
+H^V},dBp!
import java.util.List; qFsg&<
7J_f/st
import org.flyware.util.page.Page; YNQ6(HA
vYm&AD
import net.sf.hibernate.HibernateException; LkbvA
^DCv-R+p
/** Oj|p`Dzh
* @author Joa lL+^n~g
*/ kp>Z /kt
publicinterface UserDAO extends BaseDAO { 36Y[7m=
I z=w2\r
publicList getUserByName(String name)throws Xs,PT
F>-@LOqHy
HibernateException; s\1_-D5]Z
.nY6[2am
publicint getUserCount()throws HibernateException; g4qdm{BL
xwp?2,<
publicList getUserByPage(Page page)throws 7;-i_&vws
qN,FX#DP
HibernateException; vgp%;-p(
CH+&
} "9T`3cM0
U4I` xw'
Oqe.t;E 0}
>u#VHaB
r%mTOLef
java代码: \B ^sJ[n
tNf" X!
A
=#-u&l
/*Created on 2005-7-15*/ ?{P6AF-xcf
package com.adt.dao.impl; KcF+!;:
Q3{&'|}^2
import java.util.List; e(% Solkm?
!OVEA^6
import org.flyware.util.page.Page; s^@Cq=
H 1X]tw.
import net.sf.hibernate.HibernateException; f0bV]<_9
import net.sf.hibernate.Query; M{RZ-)IC
+7OT`e
%q
import com.adt.dao.UserDAO; x#VUEu]8
nL20}"$E
/** 17 iq
* @author Joa _%%"Y}
*/ t"vO&+x
public class UserDAOImpl extends BaseDAOHibernateImpl .TS=[WGMS
GQBN-Qv
implements UserDAO { fzG1<Gem
!T(Omve)
/* (non-Javadoc) C}EDl2
* @see com.adt.dao.UserDAO#getUserByName
xTJ5VgG
qyfxT Q5
(java.lang.String) s""8V_,;
*/ JLn<,Gn)<\
publicList getUserByName(String name)throws 5FKd{V'
[
[CXMbD`*
HibernateException { x}j41E}
String querySentence = "FROM user in class x^skoz
_\;#a
com.adt.po.User WHERE user.name=:name"; +Z]%@"S?
Query query = getSession().createQuery vBnHG-5;P
i_ T dI
(querySentence); N\&;R$[9:
query.setParameter("name", name); dF]8>jBOL
return query.list(); 7E)7sd
} 2MeavTr
.w)t<7 y
/* (non-Javadoc) 1R9/AP
* @see com.adt.dao.UserDAO#getUserCount() W RaO.3Q@.
*/ ZfikNQU9r
publicint getUserCount()throws HibernateException { ]~ UkD*Ct
int count = 0; ob
#XKL
String querySentence = "SELECT count(*) FROM rM |RGe
l/NK.Jr
user in class com.adt.po.User"; HpAZ{P7
Query query = getSession().createQuery _,~zy9{,
D*,H%xA
(querySentence); 0MPDD%TP
count = ((Integer)query.iterate().next AFED YRX
cf!R
()).intValue(); itvdzPO
return count; [L^#<@S
} a-y5 \x
c*Nbz,:
/* (non-Javadoc) w[-Bsf
* @see com.adt.dao.UserDAO#getUserByPage 9Z
4R!Q
mNKa~E
(org.flyware.util.page.Page) ZeZwzH)BD
*/ hNy S
publicList getUserByPage(Page page)throws k#n=mm'N9
%-CC_R|0$
HibernateException { pnU
g:R@
String querySentence = "FROM user in class Y~xZ{am
jFfki.H
com.adt.po.User"; i|mA/
e3b
Query query = getSession().createQuery Q<pM
tW
-C+vmY*@
(querySentence); 6wgOmyJx
query.setFirstResult(page.getBeginIndex()) %*nZ,r
.setMaxResults(page.getEveryPage()); _#:1Axx1
return query.list(); ]u ';zJ.
} ,+&j/0U
rpmDr7G
} 8^lXM-G-
Xc^~|%+
8h97~$7)
Jk*MxlA.b
9':$!Eoq
至此,一个完整的分页程序完成。前台的只需要调用 T2{+fRvN
KX`,7-
userManager.listUser(page)即可得到一个Page对象和结果集对象 %Y TIS*+0
wah`
的综合体,而传入的参数page对象则可以由前台传入,如果用 "6i9 f$N
4SYN$?.Mp
webwork,甚至可以直接在配置文件中指定。 b}:Z(L,\
(L1`]cp
下面给出一个webwork调用示例: W#!\.m`5
java代码: \2jY)UrQs
kXWx )v
$u :=lA:N
/*Created on 2005-6-17*/ Gf?KpU
package com.adt.action.user; z0sB*5VH
FQyiIT6
import java.util.List; 1yu!:8=ee
&%lhov
import org.apache.commons.logging.Log; i*<,@*
import org.apache.commons.logging.LogFactory; $$@Tgkg?o
import org.flyware.util.page.Page; ? &O$ayG77
|};~YMH
import com.adt.bo.Result; !NCT) #G`
import com.adt.service.UserService; C6n4OU
import com.opensymphony.xwork.Action; Li2)~4p><
hk
I$ow (
/** J:5n/m^A
* @author Joa c nzPq\
*/ llzl-2`/
publicclass ListUser implementsAction{ pqe**`z@y
D1f=f88/}
privatestaticfinal Log logger = LogFactory.getLog /y 0 )r.R
1f=L8Dr
(ListUser.class); Vr*t~M>
M Pt7 /
private UserService userService; ",}VB8K
+3C
S3fTq
private Page page; N ]duv~JS
Z9U*SS5s,
privateList users; [Ue>KG62=
Ur`v*LT}~
/* H)S3/%.|
* (non-Javadoc) (/Ubw4unI
* Cn,jLy
* @see com.opensymphony.xwork.Action#execute() AKpux,@xB
*/ a-3~HH
publicString execute()throwsException{ 1$^{Uma
Result result = userService.listUser(page); )"1D-Bc\Q
page = result.getPage(); nXN0~,+
users = result.getContent(); I$Z"o9"
return SUCCESS; 3!,%;Vz=
} x!< C0N>?z
/eI38>v
/** WFkXz*7B
* @return Returns the page. 9$ _}E`
*/ ~ e"^-x
public Page getPage(){ 6+It>mnR
return page; 5`+*({
} 3] !(^N>V
&EQov9P7
/** dlWw=^
* @return Returns the users. wy^>i$TC
*/ j'7FTVmJ
publicList getUsers(){ 6wF?FtT
return users; 8\yH7H
} #*9*[Xbi
oCduY2
/** !{4p+peqJV
* @param page snyx$Qx(
* The page to set. t*DM^.@
*/ F/!C=nS
publicvoid setPage(Page page){ v7ae^iU
this.page = page; #&@&BlIe
} 5'o.v^l
OxD\e5r
/** !PO(Bfd
* @param users S"Efp/-
* The users to set. hP7nt
*/ rGN-jb)T+
publicvoid setUsers(List users){ ^=t yf&"
this.users = users; l/TH"z(
} H
fRxgA@
@p!["v&
/** %o?fE4o'
* @param userService p@!"x({@l
* The userService to set. 0S' EnmG
*/ wo*/{KFvh
publicvoid setUserService(UserService userService){ ]03!KE
this.userService = userService; eo@:@O+bm
} E&97;VH
} X=DJOepH'
.M_;mhRI
fxc~5~$>
MHgS5b2
5B(|!Xq;I
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 1s*I
Oy H:
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 02S Uyv(Mt
>s1HQSe66
么只需要: n%ld*EgY
java代码: Uqkh@-6-
)Dv"seH.
'2%hc\P6P
<?xml version="1.0"?> Z3S\@_/;
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork <1hwXo
ZI5UQH/
1.0//EN" "http://www.opensymphony.com/xwork/xwork- {B[i|(xQx
6H3_qx
1.0.dtd"> 3 \kT#nr
H-I*;
<xwork> [V1gj9t=,
f(9w FT
<package name="user" extends="webwork- &*0!${B
#BM *40tch
interceptors"> FCI38?`%
>;HXH^q
<!-- The default interceptor stack name ^%\p; yhL
NMOTWA}2
--> ;7qk9rz4
<default-interceptor-ref Q>X ;7nt0
F.O2;M|x
name="myDefaultWebStack"/> jP+4'O!s[
Wqy8ZgSC
<action name="listUser" jkfI,T
bcOX/
class="com.adt.action.user.ListUser"> z.{yVQE
<param ]ImS@!Ajjx
xv1$,|^ts
name="page.everyPage">10</param> `5x,N%9{
<result m
81\cg
c5U1N&k5&
name="success">/user/user_list.jsp</result> +K+
== mO&
</action> p-ry{"XA
c-gaK\u}j}
</package> HLk/C[`u,
QI!:+8
</xwork> L9G=+T9
,$CZ(GQ
!n
!~Bw
Ot v{#bB$
+y -:(aP
D4`7,JC}<
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 d'DS7F(c{
tMupX-V
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。 ]jM D'vg^b
'zRd?Z>%
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 Ndx='j0
t-/%|@?D
RCoz;|c`P
F[~qgS*;
#U!J2240
我写的一个用于分页的类,用了泛型了,hoho ~lQ]PKJ"
[D/q%
java代码: 3`-[95w
t$s)S>
Rk`c'WP0*
package com.intokr.util; GfVMj7{
<y!6HJ"
import java.util.List; hj9bMj
x~KS;hA
/** I /RvU,
* 用于分页的类<br> b/<4\f
* 可以用于传递查询的结果也可以用于传送查询的参数<br> :Rq@ %rL
* f61~%@fE
* @version 0.01 b/E1v,/<
* @author cheng 1=#`&f5f&
*/ gSC8qip
public class Paginator<E> { mAXTO7
privateint count = 0; // 总记录数 a!wPBJJ
privateint p = 1; // 页编号 Be?mIwc_g
privateint num = 20; // 每页的记录数 #Etz}:%W
privateList<E> results = null; // 结果 >Utn[']~
? p\'S
w:
/** \#~~,k
6f
* 结果总数 w)3LY F
*/ >oLM2VJ
publicint getCount(){ 4|x5-m+T
return count; vE{QN<6T
} 4oCnF+(
I]TL#ywF
publicvoid setCount(int count){ CYG'W FvZZ
this.count = count; ?c(f6p?%
} ZH/|L?Q1U
qAkx52v6
/** ZH.l^'(W
* 本结果所在的页码,从1开始 /V:%}Z
* C\EZ8
* @return Returns the pageNo. iZ)7%R?5
*/ #& Rx(
publicint getP(){ XWk/S $-d
return p; ?T?%x(]I
}
k|a{|2p
u{exQ[,E
/** 6lsU/`.
* if(p<=0) p=1 "RZ)pav?
* -N*g|1rpa
* @param p %k1*&2"1#
*/ (\#j3Y)r
publicvoid setP(int p){ <S TwylL
if(p <= 0) V/J[~mN9
p = 1; dYk)RX`}7!
this.p = p;
PDM>6U
} Mx0c
#d.
R4pbi=
/** TkmN.@w_C
* 每页记录数量 N f1) 5
*/ aD24)?db-
publicint getNum(){ }+ I
8l'
return num; Cg8{NNeD
} +oe
~j\=
X!nI{PE
/** bAt!9uFn
* if(num<1) num=1 tE<L4;t
*/ c$@,*c
0n
publicvoid setNum(int num){ )Q FT$rmX
if(num < 1) ~"+[VE5
num = 1; (|h<{ -L
this.num = num; Q
Gn4AW_
} oKzV!~{0M;
3l<)|!f]g
/** st/Tb/
* 获得总页数 f}nGWV%,
*/ (;C_>EL&u
publicint getPageNum(){ \MK)dj5uUJ
return(count - 1) / num + 1; =:o)+NE
} uh`~K6&*\w
TJLz^%t
/** ]-L/Of6F)|
* 获得本页的开始编号,为 (p-1)*num+1 B~yD4^
*/ Qh?q0VKU^
publicint getStart(){ s13Iu#
return(p - 1) * num + 1; $?ke "
} +~8/7V22
YWd:Ok0
/** D;d'ss;
* @return Returns the results. f5mk\^
*/ gd#
publicList<E> getResults(){ g)u2
return results; FSc730rM
} 1[u{3lQ
zVkHDT[
public void setResults(List<E> results){ r$G;^
this.results = results; Hagj^8
} 9bqfZ"6nXY
q\d'}:kfu
public String toString(){ }5zH3MPQH
StringBuilder buff = new StringBuilder BU]9eF!>h
ctH`71Y
(); w4RP*Da?:
buff.append("{"); gHYYxhW$
buff.append("count:").append(count); C0KP,JS&
buff.append(",p:").append(p); ^9qncvV
buff.append(",nump:").append(num); B@.U\.
buff.append(",results:").append A -c3B+
k3^S^Bv\
(results); sL+/Eeb` c
buff.append("}"); j31
Sc3vG
return buff.toString(); &eK8v]|"W
} <Pg.N
]*I&104{
} V..m2nQj
Q9FY.KUM
{IqbO>|"O_