Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 F rd>+
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 &[b(Lx|i
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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 s7?d_+O
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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 T3bYj|rh=
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。 pN=>q<]L
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分页支持类: ROi_k4Fj
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java代码: \ v2-}jU(
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package com.javaeye.common.util; j6GR-WQ]t
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import java.util.List; Ve\.7s
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publicclass PaginationSupport { +?'a2pUS
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publicfinalstaticint PAGESIZE = 30; E>c*A40=.n
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privateint pageSize = PAGESIZE; R+# g_"1@p
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privateList items; wd*V,ZN7
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privateint totalCount; e'X"uH Xt.
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privateint[] indexes = newint[0]; {W'{A
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privateint startIndex = 0; h'B0rVQia>
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public PaginationSupport(List items, int ^tL]QE?|
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totalCount){ =zW`+++3
setPageSize(PAGESIZE); W~& QcSWqD
setTotalCount(totalCount); (V>/[Ev
setItems(items); 3Vk<hBw2
setStartIndex(0); TBmmC}PEd
} =>*9"k%m
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public PaginationSupport(List items, int _^h?JTU^
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totalCount, int startIndex){ %GigRA@no
setPageSize(PAGESIZE); #]2,1dJ
setTotalCount(totalCount); ]RuH6d2d|
setItems(items); |!cM_&
setStartIndex(startIndex); mr+8[0
} vv1W <X0e<
& &:ZY4`
public PaginationSupport(List items, int ,-V7~gM%}
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totalCount, int pageSize, int startIndex){ 5XZ\7Z|
setPageSize(pageSize); iza.' Mm~
setTotalCount(totalCount); `G2!{3UD
setItems(items); YR.f`-<Z
setStartIndex(startIndex); Mb+CtI_'
} uDMyO<\
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publicList getItems(){ 2 W Wr./q
return items; @rlL'|&X*
} \GCT3$
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publicvoid setItems(List items){ J%P{/ nR
this.items = items; X?SLYm@v
} J5zu}U?
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publicint getPageSize(){ O7xBMqMf
return pageSize; xL|4'8
} D n}TO*
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publicvoid setPageSize(int pageSize){ :Oc&{z?q
this.pageSize = pageSize; ?>iZ){0,
} R]y9>5 'U
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publicint getTotalCount(){ v]m#+E
return totalCount; QD^"cPC)mM
} t_iZ\_8
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publicvoid setTotalCount(int totalCount){ W4S]2P>T
if(totalCount > 0){ 9|2LuHQu+
this.totalCount = totalCount; U/:x<Y$ tj
int count = totalCount / A[ N>T\
F
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pageSize; m@y_Wt
if(totalCount % pageSize > 0) .KxE>lJbqM
count++; sX#7;,Ft7
indexes = newint[count]; % ^&D,
for(int i = 0; i < count; i++){ *Vp$#Rb
indexes = pageSize * P"k,[ZQ
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} qR8 BS4q_p
}else{ etL)T":XV
this.totalCount = 0; vA#?\j2
} b*o,re)Dj
} jAOD&@z1
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publicint[] getIndexes(){ (N$$N:ac[t
return indexes; G9jlpf5>
} -0:B2B
hionR)R4
publicvoid setIndexes(int[] indexes){ ,E8~^\HV
this.indexes = indexes; -1 _7z{.
} 9p9-tJfH.
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publicint getStartIndex(){ .E0*lem'hE
return startIndex; c$]NXKcA
} Zbjj>*2%^
f n'N^
publicvoid setStartIndex(int startIndex){ +ywd(Tuzm
if(totalCount <= 0) eE[/#5tK
this.startIndex = 0; ?mW;%d~]
elseif(startIndex >= totalCount) n`g:dz
this.startIndex = indexes RYKV?f#[H
eO=!(
[indexes.length - 1]; k<\]={|=
elseif(startIndex < 0) 7x:j4
this.startIndex = 0;
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else{ O7\)C]A
this.startIndex = indexes Z|a\rNv
parC~)b_
[startIndex / pageSize]; fY9/u =
} /'0,cJnm
} -}r(75C
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publicint getNextIndex(){ sYY=MD
int nextIndex = getStartIndex() + od~`q4p1(-
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pageSize; 7<c&)No;
if(nextIndex >= totalCount) P;!4 VK
return getStartIndex(); QprzlxB
else <jRs/?1R
return nextIndex; 05m/iQ
} {cBLm/C
Y4dTv<=K@i
publicint getPreviousIndex(){ cP MUu9du
int previousIndex = getStartIndex() - UT7".1H
&tw
pageSize; =rDIU&0Y
if(previousIndex < 0) u(|k/~\
return0; =.Q|gZ
else ;j/-ndd&&
return previousIndex; jZ>'q/
} )04lf*ti
';?b99
} /A) v$Bv=
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抽象业务类 JSQ*8wDcl
java代码: 84*Fal~Som
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/** D?_#6i;DJ
* Created on 2005-7-12 ^y"$k
*/ =7`0hS<@F
package com.javaeye.common.business; 7a:mZ[Vh
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import java.io.Serializable; __V6TDehJ$
import java.util.List; `-N&cc
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import org.hibernate.Criteria; hrRX=
import org.hibernate.HibernateException; S
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import org.hibernate.Session; V
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import org.hibernate.criterion.DetachedCriteria; hOx">yki
import org.hibernate.criterion.Projections; Lay+)S.ta[
import B1A5b=6G<
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org.springframework.orm.hibernate3.HibernateCallback; R`:NUGR
import ^50/.Z>
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org.springframework.orm.hibernate3.support.HibernateDaoS <`q|6XWL
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upport; a".uS4x
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import com.javaeye.common.util.PaginationSupport; Mr(~
*
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public abstract class AbstractManager extends |8"~ou:.
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HibernateDaoSupport { VBssn]w
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privateboolean cacheQueries = false; <z|? C
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privateString queryCacheRegion; tH"SOGfSt
q'?:{k$%
publicvoid setCacheQueries(boolean #7U,kTj9
(K+TqJw
cacheQueries){ MNiu5-g5
this.cacheQueries = cacheQueries; sHrpBm&O4
} (;a
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publicvoid setQueryCacheRegion(String >M^
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queryCacheRegion){ DwZt.*
this.queryCacheRegion = ys;e2xekg
@"HR"@pX
queryCacheRegion; ?Y'S
/
} d/(=q
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publicvoid save(finalObject entity){ t{>66jm\R
getHibernateTemplate().save(entity); c+G: bb%p
} 7`tnoTUv
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publicvoid persist(finalObject entity){ XI\aZ\v
getHibernateTemplate().save(entity); "=<lPi
} UUY-EC7X
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publicvoid update(finalObject entity){ Ik1,?A
getHibernateTemplate().update(entity); h{sW$WA
} 2ezuP F
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publicvoid delete(finalObject entity){ *4qsM,t
getHibernateTemplate().delete(entity); tTyu,%/m
} .KT+,Y
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publicObject load(finalClass entity, .tN)H1.:B
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finalSerializable id){ ;.W0Aa
return getHibernateTemplate().load [`fq4Ky
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(entity, id); Whd4-pR8
} }C7tlA8,7
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publicObject get(finalClass entity, #s#z@F
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finalSerializable id){ 9zO3KT2
return getHibernateTemplate().get D-3/?"n
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(entity, id); 54J<ZXCs
} ].dTEzL9X
@mJN
publicList findAll(finalClass entity){ 9'toj%XQ
return getHibernateTemplate().find("from kFM'?L&
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" + entity.getName()); qW7"qw=
}
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publicList findByNamedQuery(finalString @LL&ggV?
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namedQuery){ `6mHt6"h
return getHibernateTemplate fe37T@
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().findByNamedQuery(namedQuery); Lf 0Hz")
} y-n\;d>[(
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publicList findByNamedQuery(finalString query, }7=a,1T
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finalObject parameter){ Xq>e]#gR
return getHibernateTemplate -;P<Q`{I
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().findByNamedQuery(query, parameter); Rc6
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} BE"nyTQ
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publicList findByNamedQuery(finalString query, Msd!4TrBJ
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finalObject[] parameters){ X^|oY]D
return getHibernateTemplate zK-hNDFL{
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().findByNamedQuery(query, parameters); 0= 'DDy
} : l>Ue&
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publicList find(finalString query){ rIb[gm)Rk
return getHibernateTemplate().find 5&X
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(query); [QZ~~(R
} z t,-O7I'1
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publicList find(finalString query, finalObject 9uS7G *
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parameter){ Ox~'w0c,f
return getHibernateTemplate().find Tc88U8Gc
_).'SU)>
(query, parameter); 99ha/t
} 'hekCZZ_I
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public PaginationSupport findPageByCriteria s3+O=5
d(@A
(final DetachedCriteria detachedCriteria){ m@O\Bi}=}
return findPageByCriteria 9wq%Fnt
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); Pm1
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} <Y#R]gf1
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public PaginationSupport findPageByCriteria HQ
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(final DetachedCriteria detachedCriteria, finalint __ mtZ{
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startIndex){ 9#iDrZW
return findPageByCriteria <{) 4gvH
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v
(detachedCriteria, PaginationSupport.PAGESIZE, dJLJh*=AG
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startIndex); .d"+M{I
} poe Xi\e!(
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public PaginationSupport findPageByCriteria zJnVO$A'
}=|ZEhtOp
(final DetachedCriteria detachedCriteria, finalint -1_Z*?=-
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pageSize, _#gsR"FZ$
finalint startIndex){ bY2Mw8e%
return(PaginationSupport) lXPn]iLJ
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getHibernateTemplate().execute(new HibernateCallback(){ b{I`$E<[
publicObject doInHibernate vLS9V/o
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(Session session)throws HibernateException { o(``7A@7a
Criteria criteria = \a6)t%u
9/$P_Q:3
detachedCriteria.getExecutableCriteria(session); zOE6;c81
int totalCount = Nb#7&_f=
WsV3>=@f
((Integer) criteria.setProjection(Projections.rowCount ) ,hj7
>1~`tP
()).uniqueResult()).intValue(); .]e6TFsrO
criteria.setProjection <!N;(nZ9}O
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(null); j?,*fp8
List items = A pjqSz"
7[H`;l
criteria.setFirstResult(startIndex).setMaxResults YxtkI:C?
? g{,MP5
(pageSize).list(); >Y+KL
PaginationSupport ps = D9C}Dys
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new PaginationSupport(items, totalCount, pageSize, ziycyf.d
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startIndex); Uu
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return ps; s4$m<"~
} 4sj%:
}, true); :(b3)K
} 8e@JvAaa$
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public List findAllByCriteria(final 0w['jh|,
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DetachedCriteria detachedCriteria){ +=h!?<*C8
return(List) getHibernateTemplate >Y'yM4e*
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().execute(new HibernateCallback(){ \Ep/'Tj&
publicObject doInHibernate
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(Session session)throws HibernateException { D&r8V;G[[
Criteria criteria = 8-5jr_*
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detachedCriteria.getExecutableCriteria(session); SU'1#$69F
return criteria.list(); m[{&xF|_
} nh=Us^xD
}, true); arLl8G[
} (<C%5xk
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public int getCountByCriteria(final 'Xl>,\'6
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DetachedCriteria detachedCriteria){ _~nex,;r
Integer count = (Integer) R{o*O_qX
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getHibernateTemplate().execute(new HibernateCallback(){ >1U@NK)HfY
publicObject doInHibernate D:ugP,
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(Session session)throws HibernateException { S.)7u6/_!
Criteria criteria = <M OL{jan
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detachedCriteria.getExecutableCriteria(session); \u_v7g
return 4<g72| y
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criteria.setProjection(Projections.rowCount un^IQMIh
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}N4u
()).uniqueResult(); fJw=7t-t
} ,*Z[P%<9
}, true); WJU NJN
return count.intValue(); OPY/XKyY,
} 'HWgvmw(
} bus=LAJt=
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z#J/*712
用户在web层构造查询条件detachedCriteria,和可选的 WQLL[{mhS
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 0*;9CH=BE
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PaginationSupport的实例ps。 f76|
6>BDA?
ps.getItems()得到已分页好的结果集 To8v#.i
ps.getIndexes()得到分页索引的数组 M}oj!xGB
ps.getTotalCount()得到总结果数 c^Gwri4
ps.getStartIndex()当前分页索引 ,q@(L
ps.getNextIndex()下一页索引 &/hr-5k
ps.getPreviousIndex()上一页索引 T{H#]BF<E
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 yFU2'pB
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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 /-K dCp~
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一下代码重构了。 0"<;You
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我把原本我的做法也提供出来供大家讨论吧: )|h;J4V
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首先,为了实现分页查询,我封装了一个Page类: uCP6;~Ns
java代码: YaVc9du7
1yaIV+_y/
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/*Created on 2005-4-14*/ Bx}0E
package org.flyware.util.page; LJNie*
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/** KYRm
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* @author Joa !:5`im;i
* K?Xo3W%K
*/ 1[/$ZYk:
publicclass Page { K]pKe"M
P$6f +{
/** imply if the page has previous page */ :YJ7J4
privateboolean hasPrePage; [%iUg\'7d
^Q)gsJY|I
/** imply if the page has next page */ -90ZI1O`
privateboolean hasNextPage; F%_,]^ n[
3n84YX{
/** the number of every page */ Vi?~0.Z%
privateint everyPage; gLxT6v5wk.
*L4]\wf
/** the total page number */ _czbUl
privateint totalPage; O^R:_vb3I
gKs/T'PW
/** the number of current page */ Q 9gFTLQ
privateint currentPage; (:y,CsR}4
}Uwkef.Q
/** the begin index of the records by the current ySuLt@X
zA'gb'MmW
query */ -0KbdHIKb'
privateint beginIndex; [zh4W*K_cq
"\zj][sL
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/** The default constructor */ L VU)W^
public Page(){ n<%=~1iY+
*t?~)o7
} 6N%L8Q
SZK)q
/** construct the page by everyPage 4gv.E 0Fo
* @param everyPage yYG3/Z3u5
* */ A1|7(Sow
public Page(int everyPage){ A^4kYOe
this.everyPage = everyPage; EBIa%,
} vNK`Y|u@
fNAo$O4cm
/** The whole constructor */ 0[2BY]`Z.
public Page(boolean hasPrePage, boolean hasNextPage, (ifqwl62
FD
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E*r
int everyPage, int totalPage, @tE&<[e
int currentPage, int beginIndex){ Rg8m4x w
this.hasPrePage = hasPrePage; s}[A4`EWH
this.hasNextPage = hasNextPage; 38w.sceaT
this.everyPage = everyPage; C)J_lI{^
this.totalPage = totalPage; s0\f9D
this.currentPage = currentPage; n{.*El>{
this.beginIndex = beginIndex; W?"2;](
} Msv*}^>
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/** yUD_w
* @return ~}7$uW0ol
* Returns the beginIndex. }DDVGs[
*/ 2xL!PR-
publicint getBeginIndex(){ :_o] F
return beginIndex; _uO!N(k.
} B8cBQ v
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/** LXh@o1
* @param beginIndex f%Z;05
* The beginIndex to set. 5#TrCPi6A
*/ xZ.~:V03\t
publicvoid setBeginIndex(int beginIndex){ H-/; l54E
this.beginIndex = beginIndex; 7]/dg*A )C
} S+) l[0
4T-,'P{?
/** 6?1s`{yy
* @return W"b&M%y|
* Returns the currentPage. h*;g0QBkl
*/ `G=ztL!gq
publicint getCurrentPage(){ u(V
return currentPage; ;Pol#0_(
} YVQ_tCC_!
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/** *3A3>Rwu
* @param currentPage XKz;o^1a^
* The currentPage to set. 54
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*/ EX`"z(L
publicvoid setCurrentPage(int currentPage){ ~`*1*;Q<H|
this.currentPage = currentPage; d] b~)!VW
} I! h(`
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/** Zdv.PGn
* @return xoqiRtlY:
* Returns the everyPage. p{iG{
*/ @k=cN>ZMc
publicint getEveryPage(){ D+@-XU<Lp<
return everyPage; 5kGxhD
} W4)kkJ
F^ I\X
/** $q Zc!Qc
* @param everyPage ^=eq .(>
* The everyPage to set. LYd}w(}
*/ xN#bzma
publicvoid setEveryPage(int everyPage){ vOos*&
this.everyPage = everyPage; RL?u n}Qa
} G{@C"H[$<
:7 qqjs
/** Jt##rVN
* @return zq,iLoY[R
* Returns the hasNextPage. ayV6m
*/ >;&Gz-lm
publicboolean getHasNextPage(){ |HrM_h<X
return hasNextPage; ;EgzC^2e
} 6OfdD.y
t9G}Yd[T
/** kP7a:(P_g
* @param hasNextPage HG2N-<$
* The hasNextPage to set. -'I _*fu
*/ k4S} #!
publicvoid setHasNextPage(boolean hasNextPage){ l%rx#;=u
this.hasNextPage = hasNextPage; cqeR<len
} /SnynZ.q
mgy"|\]
/** {F'Az1^I=
* @return T#\p%w9d
* Returns the hasPrePage. J__;.rnk
*/ ykxbX
publicboolean getHasPrePage(){ q^Z~IZ8IT
return hasPrePage; 'Pf_5q
} LYp'vZ!
Nc{]zWL9
/** Uh>.v |P6
* @param hasPrePage wb]*u7G
t/
* The hasPrePage to set. aGpCNc{+
*/ Hl4\M]]/&
publicvoid setHasPrePage(boolean hasPrePage){ ddoST``G
this.hasPrePage = hasPrePage; HV ;;
} D,MyI#
GtF2@\
/** Z`rK\Bc
* @return Returns the totalPage. >4,{6<|
* %PzQ\c
*/ 'nMApPl
publicint getTotalPage(){ A^pu
return totalPage; =g@R%NDNV
} zu52 p4
CE{z-_{^
/** D,k(~
* @param totalPage WElrk:b
* The totalPage to set. mKV'jm0
*/ [_h%F,_ A
publicvoid setTotalPage(int totalPage){ fCB:733H
this.totalPage = totalPage; "ml?7Xl,n
} sYI~dU2H
QjLji+L
} p"KU7-BfvC
O:1DOUYXs
u,fA!
prZ55MS.
#Rc5c+/(
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 eK9TAW
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个PageUtil,负责对Page对象进行构造: CD} Ns
java代码: Yb}w;F8(
3wZ(+<4i
T j`y J!0
/*Created on 2005-4-14*/ ^\:yf.k
package org.flyware.util.page; a'uU,Eb}#w
6)ycmu;!$
import org.apache.commons.logging.Log; N0Gf0i>
import org.apache.commons.logging.LogFactory; Uan,H1a
M`~!u/D7
/** Te;gVG *
* @author Joa :lK4
db
* p'&*r2_ram
*/ ob'n{T+lZ
publicclass PageUtil { h4Ia>^@
B20_ig:
privatestaticfinal Log logger = LogFactory.getLog \OcMiuw
H>?F8R_iq
(PageUtil.class); _S"f_W
71O3O7
/** l)Zs-V!M^\
* Use the origin page to create a new page NY@"&p'Q
* @param page a}>Dz 1R
* @param totalRecords j5\$[-';
* @return \X&
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*/ u?kD)5Nk
publicstatic Page createPage(Page page, int !qA8Zky_
a=+T95ulDy
totalRecords){ khAqYu")
return createPage(page.getEveryPage(), NhA#bn9y?
noC?k }M
page.getCurrentPage(), totalRecords); ^YKy9zkTl
} gLIT;BK
w>qCg XU3
/** (S oo<.9~
* the basic page utils not including exception H0a-(
=Y9\DeIZ
handler pcH<gF(k
* @param everyPage 'S?;J ,/
* @param currentPage J{Tq%\a3
* @param totalRecords Zhzy.u/>
* @return page ,- '4L9
*/ 6e .v&f7(
publicstatic Page createPage(int everyPage, int `U{mbw,
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currentPage, int totalRecords){ #dc1pfL!y{
everyPage = getEveryPage(everyPage); )p8I@E
currentPage = getCurrentPage(currentPage); B,_`btJh
int beginIndex = getBeginIndex(everyPage, ''S&e
\&a.}t
currentPage); .
uR M{Bs
int totalPage = getTotalPage(everyPage, m=TJDr-
g_w&"=.jBq
totalRecords); aI(>]sWJ
boolean hasNextPage = hasNextPage(currentPage, ,+._;[k
z856 nl
totalPage); >|3a
9S
boolean hasPrePage = hasPrePage(currentPage); 0@)%h&mD
frN3S
returnnew Page(hasPrePage, hasNextPage, Km3&N
everyPage, totalPage, NP/>H9Q2%
currentPage, zoP%u,XL
@Z;1 g
beginIndex); F
Z!J
} Y-p<qL|_
\k@Z7+&7
privatestaticint getEveryPage(int everyPage){ dB;3.<S=
return everyPage == 0 ? 10 : everyPage; H9`
f0(H
} xd8
*<,Wj
)ofm_R'q*
privatestaticint getCurrentPage(int currentPage){ #tjmWGo,
return currentPage == 0 ? 1 : currentPage; t`G)b&3_O
} :eOR-}p'
nrpI5t.b
privatestaticint getBeginIndex(int everyPage, int M3pjXc<O
*7" L]6
currentPage){ 4_LQ?U>$
return(currentPage - 1) * everyPage; 6;oe=Q:Q
} jtKn3m7 +p
:gI.l1
privatestaticint getTotalPage(int everyPage, int 8LJ{i%
!@g)10u
totalRecords){ 1f4bt6[
int totalPage = 0; ;/LD)$_
u+D[_yd^
if(totalRecords % everyPage == 0) x*}bo))hb
totalPage = totalRecords / everyPage; }!)F9r@\
else 8]< f$3.
totalPage = totalRecords / everyPage + 1 ; 0{) $SY
4vdNMV~
return totalPage; 'iUg[{'+
} &uM^0eM
GXX+}=b7qO
privatestaticboolean hasPrePage(int currentPage){ SwH2$:f
return currentPage == 1 ? false : true; &ZJgQ-Pc(m
} ^#e~g/
Veji^-0E
privatestaticboolean hasNextPage(int currentPage, rt4Z;
Zb''mf\
int totalPage){ g4&jo_3:p
return currentPage == totalPage || totalPage ==
xh0 xSqDM
T_#,
A0 G
0 ? false : true; -<N&0F4|*
} K`k'}(vj
nWWM2v
4MW ]EQ-
} uQeu4$k!
bAF )Bli
i0pU!`0
onte&Ed\
UQT'6* !
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 .q;ED`G
Hl7:*]l7b
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 ijUzC>O+q
:&VcB$
做法如下: z4M1D9iPY
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 ftZj}|R!
@Doyt{|T
的信息,和一个结果集List: .T.5TMiOSq
java代码: $.K?N@(W
IFuZ]CBz
H:S,\D?%2x
/*Created on 2005-6-13*/ <@,$hso7:
package com.adt.bo; HGDVOJq
>SCGK_Cr2
import java.util.List; ?tYpc_p#
UAYd?r
import org.flyware.util.page.Page; rwqv V^
/ 8gL.i$
/** sR_xe}-
* @author Joa {'bip`U.
*/ 7*+TP~WI
publicclass Result { j"7
JLe*
\4bWWy
private Page page; ;Zut@z4\
JlZ0n;
private List content; jO'|mGUM
]tt} #
/** ?m"|QS!!K
* The default constructor svhrf;3:
*/ rPiNv
30L
public Result(){ \7Cg,Xn
super(); `l]j#qshTm
} ~&VN_;j_
v}uJtBG(
/** F $yO
* The constructor using fields IazkdJX~
* Vk}49O<K/
* @param page Z(Q2Ue;}&
* @param content \t.}-u<7{
*/ TEVI'%F
public Result(Page page, List content){ XutF"9u
this.page = page; w|Aqqe
this.content = content; uJow7-FD
} m],Ud\
%XRN]tsu
/** YD[H
* @return Returns the content. pSAR/':eg
*/ HW_& !ye
publicList getContent(){ R>)MiHcCg
return content; 3 <SqoJSp
} y]
V1b{9p
'K@0Wp
/** _sMs}?^
* @return Returns the page. "Pc$\zJm;
*/ [ygF0-3ND
public Page getPage(){ +m$5a
YX
return page; #V_GOy1-
} mJ
clDHTj=~
/** :nGMtF
* @param content lrEj/"M
* The content to set. \8b6\qF/\
*/ >-cfZ9 {!
public void setContent(List content){ f~M8A.
this.content = content;
'3,\@4
} Ex(3D[WmMW
\M+L3*W
/** 'fW#7W
* @param page Ka-p& Uv1<
* The page to set. `~F5wh~
*/ Plo ,XU
publicvoid setPage(Page page){
$aP(|!g
this.page = page; 4\2V9F{s
} |!*Xl)
]
} ^PqF<d6
+V8b
{]/8skov5]
f} K`Jm_}?
l I-p_K
2. 编写业务逻辑接口,并实现它(UserManager, =xl~][
=nxKttmU0
UserManagerImpl) tJD]
(F
java代码: *i%quMv
Jh@_9/?
tS?lB05TOR
/*Created on 2005-7-15*/ 5vOC CW
package com.adt.service; }STYG`
l[Z)@bC1
import net.sf.hibernate.HibernateException; $&{IKP)u
80hme+e
import org.flyware.util.page.Page; tL(B pL'
H%i>L?J2 /
import com.adt.bo.Result; yI8tH!
Oh!(@
/** PpOlt.yui
* @author Joa P%>?[9!Nt
*/ v,1F--v
publicinterface UserManager { $|<m9CW
>S#ul?
public Result listUser(Page page)throws tFh|V
pB
f`P9ku#j}
HibernateException; Qi=*1QAkr
i$Z#9M9
} M?@pN<|
D<):ZfUbI
shFc[A,r}
<d7xt*4
=!0I_L/
java代码: ;#QhQx
&O1v,$}'
(FVX57
/*Created on 2005-7-15*/ * gqSWQ
package com.adt.service.impl; Pv){sYUh
q)I|2~Q c^
import java.util.List; hnxc`VX>g
ARB7>"
import net.sf.hibernate.HibernateException; v 81rfB5
'gTmH [be
import org.flyware.util.page.Page; ?J&)W,~
import org.flyware.util.page.PageUtil; t_c?Wp~tH
;e{5)@h$
import com.adt.bo.Result; K{DAOQ.z
import com.adt.dao.UserDAO; 7_)|I?
=0d
import com.adt.exception.ObjectNotFoundException; ZF{~ih*^u
import com.adt.service.UserManager; K0fv( !r{
;VzMU ;j
/** *xH\)|3,
* @author Joa 8vD3=yK%^
*/ |4>:M\h
publicclass UserManagerImpl implements UserManager { Mq\~`8V
'044Vm;/
private UserDAO userDAO; ]PS\#I}
z+VV}:Q
/** G[yI*/E;
* @param userDAO The userDAO to set. Zf:]Gq1
*/ >Y&KTSD"
publicvoid setUserDAO(UserDAO userDAO){ P_Uutn~
this.userDAO = userDAO; Mg? L-C
} xFb3O|TC
Rlw3!]5+2
/* (non-Javadoc) Z^_>A)<s<
* @see com.adt.service.UserManager#listUser Ft-6m%
ElR)Gd_ 8
(org.flyware.util.page.Page) km 5E)_]
*/ Ci\? ^
public Result listUser(Page page)throws ~j&?/{7I
+{-]P\oc
HibernateException, ObjectNotFoundException { F)ci9- b@
int totalRecords = userDAO.getUserCount(); fluGf
if(totalRecords == 0) S+T|a:]\7
throw new ObjectNotFoundException X"/~4\tJ"
=/Juh7[C
("userNotExist"); uqZ3Hyb
page = PageUtil.createPage(page, totalRecords); ^gg!Me
List users = userDAO.getUserByPage(page); E(Gr0#8
returnnew Result(page, users); 3|eUy_d3
} 9g@NcJ]
-Ktwo_V*
} 0m=(W^c
dY'Y5Th~
JvJ;bFXD
Q[_Ni15
J/kH%_ >Ir
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 w}k B6o]
?r3e*qJGn
询,接下来编写UserDAO的代码: "c
Pz|~
3. UserDAO 和 UserDAOImpl: 14l; *
java代码: yT:!%\F9
Pj!%ym3A
RVF F6N^
/*Created on 2005-7-15*/ R^tcr)(
package com.adt.dao; fVUKvZ}P*
L@A9{,9Pl
import java.util.List; s]x2DH+_
j|4tiv>
import org.flyware.util.page.Page; |- OHve4A
Xj,j0
import net.sf.hibernate.HibernateException; h48 bb.p2
E .;io*0
/** F#1kZ@nq
* @author Joa {B^pnLc
*/ kI+b <$:D
publicinterface UserDAO extends BaseDAO { Qp+lJAY
q/'MS[C
publicList getUserByName(String name)throws Au=kSSB
yJ J8"s~i
HibernateException; X_?%A54z?
az
bUc4M
publicint getUserCount()throws HibernateException; SLh~_ 5
e"_"vbk
publicList getUserByPage(Page page)throws 9 z*(8d
zJ_My&~
HibernateException; =t.F2'<[Z
L>:FGNf^H
} m X:bA5db
S7#0*2#[o
bZ1 0v;
`~E<Sf<M
5f3!NeI
java代码: *a4
b
:SeLkQC
Y_lCcu#OA
/*Created on 2005-7-15*/ Wa/geQE1<
package com.adt.dao.impl; mxhW|}_-j
0 r3N^_}
import java.util.List; 8;.` {'r
P:a*t[+
import org.flyware.util.page.Page; *NjMb{[ZQ
hDbHSZ
import net.sf.hibernate.HibernateException; k>-'AWH^v
import net.sf.hibernate.Query; \S5V}!_
buc*rtHfA
import com.adt.dao.UserDAO; d<?X3&J
6#-Z@fz%
/** 1eF@_Y^a!
* @author Joa LOt#1Qv
*/ U]mO7 HK
public class UserDAOImpl extends BaseDAOHibernateImpl #VR`?n?,
]E..43
implements UserDAO { ~,+[M-
't ;/,+:V
/* (non-Javadoc) g4T3?"xMB_
* @see com.adt.dao.UserDAO#getUserByName FJlsWh4,6=
Xr)g
(java.lang.String) !g/_w
*/ +}Auk|>Dc
publicList getUserByName(String name)throws '%$-]~
1W7
iip,
HibernateException { 6(sfpK'
String querySentence = "FROM user in class ugRV5bUk
7t+]z)
com.adt.po.User WHERE user.name=:name"; lDH_ Y]bM
Query query = getSession().createQuery E =
^-Z
n('VQ0b
(querySentence); A1 b6Zt
query.setParameter("name", name); P^n{Y~P=Q
return query.list(); |:/ @t
} 9XY|V<}
.Btv}b
/* (non-Javadoc) B~e7w 4
* @see com.adt.dao.UserDAO#getUserCount() Y~x`6
*/ Ic_t c
publicint getUserCount()throws HibernateException {
*X0K2|
int count = 0; )/
n29]
String querySentence = "SELECT count(*) FROM 2/UI>@By
P[6dTZ!\s
user in class com.adt.po.User"; J$<:/^t
Query query = getSession().createQuery %PSz o8.l
5auL<Pq
(querySentence); 5Bzuj`
count = ((Integer)query.iterate().next Ho:}Bn
g
<w%Yq?^
()).intValue(); >n#g9v K
return count; FC~|&
} 18J.vcP
JJ*0M(GG
/* (non-Javadoc) XC57];-
* @see com.adt.dao.UserDAO#getUserByPage 1h&)I%`?
P=}H1#
(org.flyware.util.page.Page) zl,bMtQ
*/ rZb_1E<
publicList getUserByPage(Page page)throws l6yB_M
`W
D*Q-&n
HibernateException { 8rnb
String querySentence = "FROM user in class lS>=y#i3Xv
*yL|}
com.adt.po.User"; $Cut
Query query = getSession().createQuery ]5aux
>.n
hVROzGZk
(querySentence); }u38:(^`ai
query.setFirstResult(page.getBeginIndex())
alWx=+d
.setMaxResults(page.getEveryPage()); !Q<8c =f
return query.list(); Fwg#d[:u
} !tm|A`<g#<
ZY~zpC_
} _D!M
nTK
(mu{~@Hw
2M!+gk=+
zlC^
la!1[VeL
至此,一个完整的分页程序完成。前台的只需要调用 0W!VV=j<}
VGkW3Nt0
userManager.listUser(page)即可得到一个Page对象和结果集对象 Xd90n>4S
>Lo6='G
的综合体,而传入的参数page对象则可以由前台传入,如果用 7r:nMPX
6C@0[Q\ER
webwork,甚至可以直接在配置文件中指定。 }UJdE#4
}7f 1(#{7
下面给出一个webwork调用示例: S"I#>^
java代码: H@ 1[SKBl
xP<H,og&x=
KE&InTM/j
/*Created on 2005-6-17*/ tr#)iZ\
package com.adt.action.user; ?Xy w<fMQ
oxxE'cx{g
import java.util.List; ;7B2~zL
l{B<"+8
import org.apache.commons.logging.Log; )dUd `g
import org.apache.commons.logging.LogFactory; ;+aDjO2(
import org.flyware.util.page.Page; \xa36~hh40
/zDSlj<c
import com.adt.bo.Result; YA1{-7'Q
import com.adt.service.UserService; ]JhDRJ\
import com.opensymphony.xwork.Action; 7%~VOB
Bh.6:9{
/** '_Hb}'sFI
* @author Joa
b{9HooQ{
*/ $j$\ccG
publicclass ListUser implementsAction{ vQ9xG))
f@,hO5h(_|
privatestaticfinal Log logger = LogFactory.getLog >TH-Q[
c +"O\j'
(ListUser.class); {VrAh*#h
Vj9`[1}1Z
private UserService userService; #b<lt'gC
T-<> )N5y
private Page page; uv_P{%TK
;mM\,
{Z
privateList users; 6+{ nw}e8
={wjeRp
/* O(:u( U7e
* (non-Javadoc) tZ*f~yW
* &~D.")Dz
* @see com.opensymphony.xwork.Action#execute() Nys'4kx7
*/ gFH;bZU
publicString execute()throwsException{ iZVT% A+q
Result result = userService.listUser(page); ;]8p:ME
page = result.getPage(); H/ B^N,oi
users = result.getContent(); XO8 H]
return SUCCESS; "pKGUM
} "' i [~
UJyiRP:#]>
/** yA`]%U((
* @return Returns the page. [1[[$ Dr
*/ <_FF~lj
public Page getPage(){ JsoWaD
return page; f;qKrw
} P(W\aLp
V< 9em7
/** ix_$Ok
* @return Returns the users. LRLhS<9
*/ ?!Th-Cc&m
publicList getUsers(){ B'[3kJ '
return users; &_Xv:?
} "KQ\F0/
3GuMiht5
/** ~[bMfkc3
* @param page G~mB=]
* The page to set. El8.D3
*/ 85d7IB{28
publicvoid setPage(Page page){ FKvO7? K
this.page = page; Q Kuc21
} eyl) uR
[^"(%{H
/** 3M>FU4Ug2
* @param users pdXgr)Uv
* The users to set. !WVabdt
*/ J*W;{Vty
publicvoid setUsers(List users){ ;7hX0AK
this.users = users; E&Zx]?~
} bI6V &Dd
2L{:H
/** C#u)$Ds
* @param userService @kgpq
* The userService to set. JOoLHZQ1v
*/ .L5T4)
publicvoid setUserService(UserService userService){ 5eZg+ O
this.userService = userService; +'6ea+$
} nR|uAw
} (>@syF%PB
e]y=]}A3{
8G^B%h]
36Fa9P FCc
T_|fb)G+{
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, <45dy5!Tz
2K7:gd8Ru
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 Ok.DSOT
9.w3VF_C
么只需要: vpr@
java代码: m{=~|I
K=^_Ndz
= ,E(!Sp
<?xml version="1.0"?> QH?2v
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork eNk!pI7g
J$=b&$I(
1.0//EN" "http://www.opensymphony.com/xwork/xwork- Nv$gKC6 ,G
mjr{L{H=?+
1.0.dtd"> ."@a1_F|
kjYO0!C
<xwork> ]KV8u1H>
#Ew
eG^!#
<package name="user" extends="webwork- HW%bx"r+4f
NBR'^6
interceptors"> ~}9H<K3V
KV&_^xSoh|
<!-- The default interceptor stack name v lnUN
$;j6*,H
--> ,i((;/O6
<default-interceptor-ref j*lWi0Z-
0$dNrq
name="myDefaultWebStack"/> a\j\eMC
V?=zuB?'
<action name="listUser" z&/
o
-<^Q2]PE;
class="com.adt.action.user.ListUser"> ve/6-J!5Y.
<param )(
jNd&H
lSsFI30
name="page.everyPage">10</param> lNnbd?D8
<result .Im+()b&&
u KdX4
name="success">/user/user_list.jsp</result> T{J`t*Ym
</action> )RKhEm%Vr2
6!L*q
</package> )o(F*v
|N3CoB
</xwork> g,]5&C T3v
~w}[
._'#M
d:WhP_rK9
+o70:UF %
*:\9T#h
;;J98G|1
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 YY>Uf1}*9
#a>!U'1|
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。 G6ES]
p:n^c5
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 TVh7h`Eg
:s985sEv
[
:(M<u`y>
F[giq1#
X#C7r@H
我写的一个用于分页的类,用了泛型了,hoho X{5 DPhB,
$GKm`I"
java代码: e<wj5:M|
YU"\Wd[
%l P
package com.intokr.util; @Sd:]h:f-
4 sgwQ$m)
import java.util.List; u:kY4T+Z
6_
0w>
/** v-aq".XQ
* 用于分页的类<br>
2Ab#uPBn
* 可以用于传递查询的结果也可以用于传送查询的参数<br> E|#R0n*
* q`K-T_<
* @version 0.01 ?{Z0g+B1
* @author cheng I%WK*AORM
*/ l\y*wr`
public class Paginator<E> { H ?:#Ui(p
privateint count = 0; // 总记录数 @*{BX~f
privateint p = 1; // 页编号 Hjkgy%N
privateint num = 20; // 每页的记录数 u1Yp5jp^K
privateList<E> results = null; // 结果 IYC#H}
6df&B
.gg
/** f__WnW5h
* 结果总数 h\ek2K
*/ ,H1~_|)<
publicint getCount(){ dNt|"9~&
return count; S.4YC>E
} oeKc-[r
&Rt]K
publicvoid setCount(int count){ 6)YNjh.{*
this.count = count; <plR<iI.
} &;3z 1s/
U2?gODh'
/** wLSYzz
* 本结果所在的页码,从1开始 -$ft `Ih
* [\F,\
* @return Returns the pageNo. Ox'.sq4
*/ P!ICno6[e
publicint getP(){ . +?lID
return p; ;z=C]kI6M
} \Y 4Z Q"0Q
X'4
Yofs
/** ]V("^.~$+C
* if(p<=0) p=1 ;a)\5Uy
* @zq{#7%z
* @param p 8{<cqYCR
*/ 1uQf}
publicvoid setP(int p){ H)+kN'J
if(p <= 0) Br!&Y9
p = 1; JOq<lb=
this.p = p; Q^Z}Y~.
} [SvwJIJJ
]}l!L;
/** .e+UgCwi
* 每页记录数量 `roSOX1f
*/ Oei2,3l,?
publicint getNum(){ (%!R
return num; m(P)oqwM
} c!T{|'?
s~w+bwr
/** L,/i%-J3c
* if(num<1) num=1 #|i{#~gxM
*/ 4BtdN-T}b
publicvoid setNum(int num){ l
d9#4D[#
if(num < 1) pwC/&bu
num = 1; #^V"=RbD
this.num = num; v a;wQ~&
} qZ}XjL
Y'h'8
\
/** 0/]vmDr
* 获得总页数 ".ZiR7Z:$Y
*/ uoHhp 4>^
publicint getPageNum(){ vsR ^aVwVZ
return(count - 1) / num + 1; LeCU"~
} U:e9Vq'N m
b2%[9)"I.
/** h`j gF
* 获得本页的开始编号,为 (p-1)*num+1 /XB1U[b
*/ 0xcqX!(
publicint getStart(){ uy{KV"%"^g
return(p - 1) * num + 1; 1hG O*cq!
} BI]t}7
G#v7-&Yl6
/** d`/{0 :F
* @return Returns the results. 9@B+$~:}7
*/ 2[hl^f^%,
publicList<E> getResults(){ OpE+e4~IF
return results; (?[cDw/{J:
} m`"s$\fah
KA#-X2U/
public void setResults(List<E> results){ Hkt'~L*
this.results = results; ]0le=Ee^%
} +s}28U!
E>D@#I>
public String toString(){ ZZ5yu* &
StringBuilder buff = new StringBuilder 78-:hk
quYZD6IH
(); s#[Ej&2[=
buff.append("{"); STI3|}G*P
buff.append("count:").append(count); ~s_$a8
buff.append(",p:").append(p); ^B9wmxe
buff.append(",nump:").append(num); 3!L)7Z/
buff.append(",results:").append 'c D"ZVm1
8<xy*=%
(results); ffVYlNQ7L
buff.append("}"); 3R><AFMY?
return buff.toString(); r%9Sx:F
} !
N p
oH0\6:S
} )%7A. UO)
jp]JFh;3
AtOB'=ph*