Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 Vqp3'=No
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 KvY1bMU!
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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 Ju"K"
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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 ')zf8>,
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。 RH~I/4e
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分页支持类: e+O502]
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java代码: J. $U_k
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package com.javaeye.common.util; 8fWk C<f}
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import java.util.List; m<I>NYfE
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publicclass PaginationSupport { [ XBVES8
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@
publicfinalstaticint PAGESIZE = 30; h[>Puoz
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privateint pageSize = PAGESIZE; <`")Zxf+
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privateList items; #u/5
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privateint totalCount; Btyp=wfN[
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privateint[] indexes = newint[0]; ?!a8'jfs
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privateint startIndex = 0; BI6]{ ZC"
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public PaginationSupport(List items, int 2g
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totalCount){ g27)$0&0
setPageSize(PAGESIZE); RYZM_@5$t
setTotalCount(totalCount); s_
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setItems(items); a_(T9pr
setStartIndex(0); iyTKy+3A
} 'cPE7uNT
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public PaginationSupport(List items, int JmF:8Q3H
]/[$3rPwZ
totalCount, int startIndex){ c"oJcp
setPageSize(PAGESIZE); c1ptN
setTotalCount(totalCount); L "5;<
setItems(items); M,dp;
setStartIndex(startIndex); g=e~YM85
} e'T|5I0K
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public PaginationSupport(List items, int s(pNg?R
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totalCount, int pageSize, int startIndex){ n+D93d9LP
setPageSize(pageSize); [!Zyp`:
setTotalCount(totalCount); Xk`' m[
setItems(items); {xRO.699
setStartIndex(startIndex); Q?V'3ZZF!
} tqXCj}mR
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publicList getItems(){ v~:'t\n
return items; j2s{rQQ
} eOZ"kw"uHu
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publicvoid setItems(List items){ JYrOE"!h
this.items = items; HQGH7<=Om
} TT^L)d
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publicint getPageSize(){ \[L|
return pageSize; ?fX`z(Z
} qnJs,"sn
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publicvoid setPageSize(int pageSize){ kE854Ej
this.pageSize = pageSize; 6vf<lmN
} P~h0Ul
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publicint getTotalCount(){ [z,6 K=
return totalCount; .TO#\!KBv
} -cgMf\YF
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publicvoid setTotalCount(int totalCount){ l0lvca=;
if(totalCount > 0){ q"VC#97`
this.totalCount = totalCount; l*b0uF
int count = totalCount / @me ( pnD
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pageSize; BHpj_LB-P
if(totalCount % pageSize > 0) Ww
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count++; ZY*_x)h+#7
indexes = newint[count]; (97&mhs3
for(int i = 0; i < count; i++){ tZygTvK/S
indexes = pageSize * ^K0oJg.E
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i; y*T@_on5
} 8qwPk4
}else{ wit
this.totalCount = 0; glZjo
} ld7B{ ?]
} kiu#THF
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publicint[] getIndexes(){ XGAR8=tic
return indexes; uQ3W =
} Ygc.0VKMR
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publicvoid setIndexes(int[] indexes){ x,Z:12H0
this.indexes = indexes; zO((FQ
} ZJV;&[$[
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publicint getStartIndex(){ ql7N\COoq
return startIndex; t;W'<.m_
} Cf.(/5X
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publicvoid setStartIndex(int startIndex){ :?:R5_Nd=
if(totalCount <= 0) I@ D<rjR
this.startIndex = 0; Qn \=P*j
elseif(startIndex >= totalCount) Z9zsvg
this.startIndex = indexes ~Gh9m]b
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[indexes.length - 1]; WD|pG;Gq
elseif(startIndex < 0) *~^M_wej
this.startIndex = 0; wp<f{^ et
else{ y<m}dW6[\
this.startIndex = indexes /J!~0~F
{4r } jH
[startIndex / pageSize]; OQ+kOE&
} lh-zE5;
} nQ;M@k&9eV
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publicint getNextIndex(){ bq z*90
int nextIndex = getStartIndex() + K
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pageSize; ]Uul~T
if(nextIndex >= totalCount) (S8hr,%n
return getStartIndex(); mV|Z5 =f
else ~Hvf"bvK|
return nextIndex; K QCF "
} &X)^G#
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publicint getPreviousIndex(){ BP=<TRp.
int previousIndex = getStartIndex() - .2SD)<}(9
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pageSize; sM@1Qyv&0
if(previousIndex < 0) c. uD%
return0; xd!GRJ<I
else 7o9[cq w
return previousIndex; m 3Do+!M[
} ese?;1r
1WAps#b.
} MZ_dI"J,
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抽象业务类 CPJ%<+4%b
java代码: jR"ACup(
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/** 90">l^HX=
* Created on 2005-7-12 \'+P5,
*/ r[3 2'E
package com.javaeye.common.business; Iy@6cd,)S
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import java.io.Serializable; 43Ua@KNi
import java.util.List; PDpDkcy|QM
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import org.hibernate.Criteria; dQI6.$?
import org.hibernate.HibernateException; moE!~IroG
import org.hibernate.Session; gCaxZ~o
import org.hibernate.criterion.DetachedCriteria; ~y1k2n
import org.hibernate.criterion.Projections; gqDSHFm:
import ZQ[ s/
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org.springframework.orm.hibernate3.HibernateCallback; ?'^yw C`
import U\6Ee-1#_
h-5] nL3
org.springframework.orm.hibernate3.support.HibernateDaoS `A$zLqz)Vm
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upport; 2Jqr"|sw
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import com.javaeye.common.util.PaginationSupport; u=ZZ;%Rvd
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public abstract class AbstractManager extends 8xYeaK
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HibernateDaoSupport { ]?s^{
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privateboolean cacheQueries = false; MG4(,"c!
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privateString queryCacheRegion; Z"E2ZSa0
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publicvoid setCacheQueries(boolean \+)AQ!E
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cacheQueries){ S=3 H.D!f
this.cacheQueries = cacheQueries; <Gz* 2i
} }PzHtA,V
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publicvoid setQueryCacheRegion(String DhT8Kh{
-{Fy@$!
queryCacheRegion){ #z9@x}p5g
this.queryCacheRegion = 1V;,ZGI*
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queryCacheRegion;
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} %RXFgm!{f
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publicvoid save(finalObject entity){ J pKCux
getHibernateTemplate().save(entity); L[lS
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} ?]0bR]}y
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publicvoid persist(finalObject entity){ b#:!b
getHibernateTemplate().save(entity); /y-8dgv0a
} / a$B8,
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publicvoid update(finalObject entity){ Y{
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getHibernateTemplate().update(entity); XVYj
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} @O)1Hnm
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publicvoid delete(finalObject entity){ R^Y_i
getHibernateTemplate().delete(entity); |4F'Zu}g>
} |/;X-+f8
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publicObject load(finalClass entity, k9iB-=X?4s
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finalSerializable id){ &Tk@2<5=
return getHibernateTemplate().load @!%HEs!# #
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(entity, id); A'T: \Wl
} en29<#8TO
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publicObject get(finalClass entity, |. LE`
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finalSerializable id){ xU'% 6/G
return getHibernateTemplate().get V)cL=4G
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(entity, id); U46Z~B
} ]/od p/jm
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publicList findAll(finalClass entity){ h2vD*W
return getHibernateTemplate().find("from SaA-Krn
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" + entity.getName()); SHN'$f0Mb
} }&LLo
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publicList findByNamedQuery(finalString myDcr|j-a
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namedQuery){
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return getHibernateTemplate 8Xz \,}$O
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().findByNamedQuery(namedQuery); 1D)=q^\I
} ?Z"<&tsZ
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publicList findByNamedQuery(finalString query, p-B
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{
finalObject parameter){ .a
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return getHibernateTemplate >jpkR
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().findByNamedQuery(query, parameter); _rvO#h
} kTm>`.kKJ=
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publicList findByNamedQuery(finalString query, 3/4r\%1b+
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finalObject[] parameters){ *."50o=T
return getHibernateTemplate Ogp@!
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().findByNamedQuery(query, parameters); 1ika'
} g)^g_4
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publicList find(finalString query){ YCo qe,5
return getHibernateTemplate().find }Z8DVTpX}
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(query); 0R}F(tjw
} nBGcf(BE.$
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publicList find(finalString query, finalObject d2O x:| <)
Q ;$NDYV1
parameter){ NnqAr ,
return getHibernateTemplate().find &v<Am%!N
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(query, parameter); ?m dGMf)
} 5ii:93Hlj
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public PaginationSupport findPageByCriteria )jed@?
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(final DetachedCriteria detachedCriteria){ T:!Re*=JJ
return findPageByCriteria (GbZt{.
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); *&~wl(+O=
} </9@RO
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public PaginationSupport findPageByCriteria {Zrf>ST
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(final DetachedCriteria detachedCriteria, finalint e\'=#Hw
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startIndex){ lW3wmSWn%
return findPageByCriteria d @>1m:p
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(detachedCriteria, PaginationSupport.PAGESIZE, K)9+3(?
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startIndex); P2sM3C
} 's 'H&sa
: 5<u!-}
public PaginationSupport findPageByCriteria Q'Vejz/
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(final DetachedCriteria detachedCriteria, finalint AMc`qh
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pageSize, +/DT#}JE
finalint startIndex){
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return(PaginationSupport) HR$;QHl~F
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getHibernateTemplate().execute(new HibernateCallback(){ *e
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publicObject doInHibernate n
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(Session session)throws HibernateException { V25u_R`{
Criteria criteria = oO][X
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detachedCriteria.getExecutableCriteria(session); ]j57Gk%z
int totalCount = "D?:8!\!
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((Integer) criteria.setProjection(Projections.rowCount fm&pxQjg
-VkPy<)
()).uniqueResult()).intValue(); v `7` '
criteria.setProjection N_| '`]D
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(null); rxQ&N[r2
List items = ]]8^j='P'
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criteria.setFirstResult(startIndex).setMaxResults &~#y-o"
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(pageSize).list(); iBaz1pDc
PaginationSupport ps = &20}64eW%
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new PaginationSupport(items, totalCount, pageSize, &M*f4PeXb
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startIndex); y sFp`
return ps; [WW ~SOJe
} .ly K
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}, true); ZOY zCc(d
}
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public List findAllByCriteria(final b?nORWjC
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DetachedCriteria detachedCriteria){ j/uu&\e
return(List) getHibernateTemplate 2^4OaHY88
)l[bu6bM
().execute(new HibernateCallback(){ g0>Q* x
publicObject doInHibernate i;mA|
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(Session session)throws HibernateException { l{4rKqtX
Criteria criteria = H/N4tWk"
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detachedCriteria.getExecutableCriteria(session); :FX|9h
return criteria.list(); O7lFg;9c`
} a+PVi
}, true); K | '`w.
} ?yy,3:
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public int getCountByCriteria(final p^*A&7d:P
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DetachedCriteria detachedCriteria){ 1AAOg+Y@U"
Integer count = (Integer) v]X*(e
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate h"t\x}8qq
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(Session session)throws HibernateException { VQl(5\6O
Criteria criteria = ,'&H`h54
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detachedCriteria.getExecutableCriteria(session); y87oW_"h
return /nB|Fo_&Q
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criteria.setProjection(Projections.rowCount 'e:(61_
e]-%P(}Z
()).uniqueResult(); FP>.@ Y
} xA SH-9
}, true); ]3]=RuQK2
return count.intValue(); 3H,?ZFFGz
} J/B`c(
} jchq\q)_z
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用户在web层构造查询条件detachedCriteria,和可选的 VCQo3k5
{
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 v:?l C<,
oMHTB!A=2
PaginationSupport的实例ps。 6QAhVg: A
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ps.getItems()得到已分页好的结果集
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ps.getIndexes()得到分页索引的数组 6|Xe ],u
ps.getTotalCount()得到总结果数 s"B2Whe
ps.getStartIndex()当前分页索引 D`3`5.b
ps.getNextIndex()下一页索引 FA!!S`{\
ps.getPreviousIndex()上一页索引
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 Eo>EK>
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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 Fs&r^ [/b
t ^~Qv
一下代码重构了。 FaQc@4%o
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我把原本我的做法也提供出来供大家讨论吧: nYE%@Up
OXI>`$we
首先,为了实现分页查询,我封装了一个Page类: n50WHlMtt
java代码: :B:6ezDF6
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/*Created on 2005-4-14*/ %S/?Ci
package org.flyware.util.page; 1P?|.W_^1
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/** H{hzw&dZ<P
* @author Joa YO9;NA{sH
* S? #6{rx
*/ v1z
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publicclass Page { %rJ'DPs
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/** imply if the page has previous page */ 7=gcdfW,;x
privateboolean hasPrePage; UCJx{7
!cW!zP-B*p
/** imply if the page has next page */ Up5 |tx7
privateboolean hasNextPage; E8BIb 'b;
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/** the number of every page */ |#yH,f
privateint everyPage; .FG%QF F~
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/** the total page number */ JJK-+a6cX
privateint totalPage; Rqr>B(|
rFaG-R
/** the number of current page */ ty'/i!/\
privateint currentPage; 2'u%
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/** the begin index of the records by the current LGK@taw^
_!,Ees=b
query */ L~AU4Q0o
privateint beginIndex; .wB'"z8L
gloJ;dEB
d/!\iLF
/** The default constructor */ mM:%-I\$
public Page(){ -e"A)Bpl(
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} ;GIA`=a%
w[C*w\A\M
/** construct the page by everyPage E+lr{~
* @param everyPage Jv} &8D
* */ 51Vqbtj^
public Page(int everyPage){ f-p$4%(
this.everyPage = everyPage; -iKoQkHt
} _s*p$/V\
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/** The whole constructor */ -Aojk8tc
public Page(boolean hasPrePage, boolean hasNextPage, Y&H<8ez
+lb&_eD
nW}jTBu_K+
int everyPage, int totalPage, i%[+C
int currentPage, int beginIndex){ [+Fajo;0
this.hasPrePage = hasPrePage; a~ dgf:e`
this.hasNextPage = hasNextPage; !o1IpTN
this.everyPage = everyPage; '$), i>6gJ
this.totalPage = totalPage; TD%&9$F
this.currentPage = currentPage; )Xa_ry7
this.beginIndex = beginIndex; 05g %5vHF
}
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/** fv k(eWB
* @return 7Mk>`4D'c
* Returns the beginIndex. #ID
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*/ ) J.xQ}g
publicint getBeginIndex(){ "=1gA~T
return beginIndex; VXW*LEk
} `!$6F:d_l
(;&}\OX6nm
/** KIp^|
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* @param beginIndex '~
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* The beginIndex to set. 3dlY_z=0
*/ D Q30\b"gU
publicvoid setBeginIndex(int beginIndex){ Q6D>(H#"0
this.beginIndex = beginIndex; ,H%[R+)
} {2YqEX-I*
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/** }0tHzw=#%e
* @return 4.^T~n G
* Returns the currentPage. #:By/9}-
*/ xy
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publicint getCurrentPage(){ mP Hto-=fB
return currentPage; c@Br_-
} qYJ<I'Ux O
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/** ~_Fx2T:X
* @param currentPage ?dbSm3
* The currentPage to set. J/Lf(;C_
*/ L]8z6]j*
publicvoid setCurrentPage(int currentPage){ L""ZI5J{F9
this.currentPage = currentPage; J]#rh5um
} FzcXSKHV%
cc3B}^@p=
/** ^2);*X>
* @return GcDA0%i
* Returns the everyPage. L9N}lH
*/ 9cHo~F|ur
publicint getEveryPage(){ Rk7F;2
return everyPage; .{\eco
} qdn_ZE
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/** lg8@^Pm$r;
* @param everyPage /]^Y\U ^
* The everyPage to set. ^C1LQZ
*/ KE ?NQMU
publicvoid setEveryPage(int everyPage){ G%FZTA6a
this.everyPage = everyPage; jU~ x^Y
} e5 L_<V^Jo
WG3!M/4r H
/** \pfa\,rW
* @return w;yzgj:n&f
* Returns the hasNextPage. 3]GMQA{L)
*/ FR[I~unqD
publicboolean getHasNextPage(){ vi
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return hasNextPage; <g%A2lI
} Ln2FG4{
jLM([t
/** l)*(UZ"
* @param hasNextPage |Q%P4S"B?
* The hasNextPage to set. V:'F_/&X?
*/ ZnRT$ l O
publicvoid setHasNextPage(boolean hasNextPage){ 5{oc
this.hasNextPage = hasNextPage; v@tEHRadz
} J@2wPKh?Yp
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/** )~)l^0X
* @return nH&z4-1Y?
* Returns the hasPrePage. NLY=o@<
*/ $8rnf
publicboolean getHasPrePage(){ '(FC
return hasPrePage; IycZ\^5 *-
} A5J41yH
v}N\z2A
/** |(Mxbprz
* @param hasPrePage {'tfU
* The hasPrePage to set. $BMXjXd}
*/ mjWU0.
publicvoid setHasPrePage(boolean hasPrePage){ Y|Q(JX
this.hasPrePage = hasPrePage; E`I(x&_
} n)"JMzjQ<
-f&vH_eK
/** !5(DU~S*@S
* @return Returns the totalPage. l[c '%M |N
* 0t%]z!
*/ e}1Q+h\
publicint getTotalPage(){ m9A%Z bQ^
return totalPage; " Q?~LB
} Mq)]2>"v
(87| :{
/** RW+u5Y
* @param totalPage qvSYrnpn
* The totalPage to set. :Q> e54]'&
*/ p$9Aadi]
publicvoid setTotalPage(int totalPage){ / Qd` ?
this.totalPage = totalPage; U,#x\[3!Jt
} lQ`=PFh
'0+~]4&}q
} pQBn8H|Y
#| _VN %!
m..ajYSQ
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nH?6o#]N
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 \hgd&H0UU
P0}{xq'k9v
个PageUtil,负责对Page对象进行构造: =yZq]g6Q
java代码: 3\@2!:>
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88v8lt;R
/*Created on 2005-4-14*/ 0>Snps3*Z
package org.flyware.util.page; .)b<cH~%
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import org.apache.commons.logging.Log; [oVM9Q
import org.apache.commons.logging.LogFactory;
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zp;!HP;/=
/** 1*u]v{JJ(
* @author Joa >-I <`y-H
* 4T(d9y
*/ O*l,&5
publicclass PageUtil { }x`Cnn
@@H_3!B%4v
privatestaticfinal Log logger = LogFactory.getLog GNMOHqg4
[w'Q9\,p
(PageUtil.class); |-}.Y(y
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/** H%@f ^
* Use the origin page to create a new page 5OI.Ka
* @param page B1)Eo2i#
* @param totalRecords Fb(@i
* @return bPxL+
+
*/ g77M5(ME
publicstatic Page createPage(Page page, int sQ#e 2
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totalRecords){ n8<?<-2
return createPage(page.getEveryPage(), 9)1Ye
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page.getCurrentPage(), totalRecords); =|z:wlOs
} ;zJb("n
hU""YP~y
/** 9KU&M"Yq&i
* the basic page utils not including exception /ovVS6Ai
d-_V*rYU
handler 4n1g4c-
* @param everyPage _M`ZF*o=c
* @param currentPage :,0(aB
* @param totalRecords ~r.R|f]IQ
* @return page (L*GU 7m;
*/ ~gd#cL%
publicstatic Page createPage(int everyPage, int Y 3ApW vS
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currentPage, int totalRecords){ BS##nS-[
everyPage = getEveryPage(everyPage); \~hrS/$[$
currentPage = getCurrentPage(currentPage); T"z<D+pN
int beginIndex = getBeginIndex(everyPage, Jr!BDg
tdH[e0x B
currentPage); gPKf8{#%e
int totalPage = getTotalPage(everyPage, r&
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totalRecords); wu.l-VmGp)
boolean hasNextPage = hasNextPage(currentPage, [j0[c9.p[
+=8wZ]
totalPage); mF;mJq<d
boolean hasPrePage = hasPrePage(currentPage); h+1|.d
skcyLIb
returnnew Page(hasPrePage, hasNextPage, 58s-RO6
everyPage, totalPage, M4C8K{}
currentPage, @vlP)"
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beginIndex); WY!\^| ,
} n>ui'}L
Dds-;9
privatestaticint getEveryPage(int everyPage){ ,-e}Xw9
return everyPage == 0 ? 10 : everyPage; 0A)0Zw
} Z0L($
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privatestaticint getCurrentPage(int currentPage){ f#!+l1GV
return currentPage == 0 ? 1 : currentPage; z^QrIl/<c2
} n?@zp<
Rs<q^w]
privatestaticint getBeginIndex(int everyPage, int Qfn:5B]tI
#<*.{"T
currentPage){ s?EQ
return(currentPage - 1) * everyPage; -O *_+8f
} 6j|Ncv
e3 v^j$
privatestaticint getTotalPage(int everyPage, int 72sqt5C]
rC-E+%y
totalRecords){ oPmz$]_Z
int totalPage = 0; u8zL[]>
;l*%IMB
if(totalRecords % everyPage == 0) $ZI]
totalPage = totalRecords / everyPage; o`S``?`^)^
else PeIx41. +s
totalPage = totalRecords / everyPage + 1 ; r
W`7<3
5b}w
return totalPage; S&!(h
{O
} zo ?RFn
Y#9W]78He
privatestaticboolean hasPrePage(int currentPage){ <_xG)vwh.
return currentPage == 1 ? false : true; i=xh;yb|
} :01d9|#
;mU;+~YE
privatestaticboolean hasNextPage(int currentPage, MR1I"gqE}I
|E1U$,s~u
int totalPage){ DJ"PP5d
return currentPage == totalPage || totalPage == ,m#
ni ?k' \\
0 ? false : true; Lm4`O%
} J>A9]%M
01?+j%k=m/
D0\>E}Y E
} <,)R`90_X6
bh.&vp.kP
K+}0:W=P
V~dhTdQ5}
[q?RJmB]
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。 c* ueI5i
* 1;4&/93o
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)-n2Bi
./F:]/Mt
做法如下: =5\*Zh1
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 %'iJVFF
1#=9DD$4
的信息,和一个结果集List: h <4`|Bg+
java代码: /i,n75/y?
X}Oe 'y
"QnYT3[l"
/*Created on 2005-6-13*/ c~vhkRA
package com.adt.bo; %hSQ\T<8[o
j,j|'7J%
import java.util.List; "TA0--6
LaQ7A,]
import org.flyware.util.page.Page; h+W$\T)
'f6H#V*C
/** (mIjG)4t
* @author Joa A08kwYxiW
*/ X84T F~2Y
publicclass Result { =cEsv&i
3mHzOs\jU
private Page page; lOt7ij(,L
e-rlk5k%f
private List content; MZV$YD^S
x4*
bhiu
/** INA3^p'w
* The default constructor F^.A~{&L
*/ fbh,V%t7
public Result(){ NT+.E[J6
super(); =^KgNQ
} |6Q5bV
H{Ewj_L
/** X)KCk2Ax
* The constructor using fields /JS_gr@DK
* S9Sgd&a9
* @param page .P1WY
* @param content Yj@Sy
*/ Xfk
DMh
public Result(Page page, List content){ xh2r?K@k>
this.page = page; ,m{R
m0
this.content = content; i% 1UUI(W
} {32m&a
7+P;s,mi7
/** Wq4<9D
* @return Returns the content. ?y?9;;
*/ I!L J&>
publicList getContent(){ ["D!IqI:
return content; /9pxEidVAS
} v.|#^A?Qx
8%K{l g"
/** $U_(e:m}f
* @return Returns the page. r-y;"h'
*/ _Ay^v#a
public Page getPage(){ q SNCBn '
return page; UQDAql
} MKfK9>a
f8;?WSGyD2
/** }<^mUG
* @param content OInl?_,,T#
* The content to set. (p5q MP]L
*/ "K(cDV Q
public void setContent(List content){ vxZ'-&;t
this.content = content; _RaE:)
} 32z4G =l
u
]"fwkL
/** 67(s\
* @param page ^.6yzlY
* The page to set. )g'J'_Sl
*/ V*@aE
publicvoid setPage(Page page){ 5REFz
this.page = page; j,.M!q]
} M=raKb?F
} -zFJ)!/?
(vG*)a
Dz0D ^(;V
_8.TPB]no
\8xSfe
2. 编写业务逻辑接口,并实现它(UserManager, -yf8
_
dAyw
UserManagerImpl) Q'n+K5&p
java代码: 23tX"e
_z#"BN
~3.*b%,
/*Created on 2005-7-15*/ qKD
package com.adt.service; 0''p29
P\MDD@
import net.sf.hibernate.HibernateException; Q` u#
"kP,v&n
import org.flyware.util.page.Page; a>OYJe
4v`/~a
import com.adt.bo.Result; 1O`V_d)
Po)U!5Tm
/** ;0Z-
* @author Joa j1;[6XG
*/ qHub+"2
publicinterface UserManager { -*k2:i`
Ca'BE#q
public Result listUser(Page page)throws 44u)F@)
`-{l$Hn9|~
HibernateException; *,z/q6
s>/Xb2\
} {g.YGO
YIRe__7-NU
n}UJ-\$
q=W.82.U
K? o p3}f?
java代码: S=,czs3N
l6bY!I>
1gV?}'jq
/*Created on 2005-7-15*/ 3*<@PXpK&
package com.adt.service.impl; \1Y|$:T/
kf'(u..G
import java.util.List; ESB^"|9
$U?]^
import net.sf.hibernate.HibernateException; svmb~n &x6
Ef`'r))
import org.flyware.util.page.Page; B{)#A?Rh.
import org.flyware.util.page.PageUtil; >UCg3uFj
TnN
ythwZ
import com.adt.bo.Result; 7dY_b
import com.adt.dao.UserDAO; i(|ug_^
import com.adt.exception.ObjectNotFoundException; 4*}&nmW
import com.adt.service.UserManager; 2A\b-;4EP
]jD\4\M}
/** /O:4u_
* @author Joa @ ;!IPiU
*/ HX2u{2$
publicclass UserManagerImpl implements UserManager { Z5'^81m$o
~
L4NK#
private UserDAO userDAO; yzK<yvN
%Lh%bqGz
/** ijOp{
* @param userDAO The userDAO to set. lNxP
*/ .6`r`|=
publicvoid setUserDAO(UserDAO userDAO){ [
iTP:8
this.userDAO = userDAO; <OEIG0
} inU5eronuj
x\Q}fk?{t
/* (non-Javadoc) =p4n@C
* @see com.adt.service.UserManager#listUser ]t)N3n6Bc
9>4 #I3
(org.flyware.util.page.Page) lC#wh2B6
*/ 9HJYrzf{%
public Result listUser(Page page)throws oH w!~c7
y>=Y MD
HibernateException, ObjectNotFoundException { uMDd Zj&
int totalRecords = userDAO.getUserCount(); `+n0a@BVB
if(totalRecords == 0) &j:e<{@
throw new ObjectNotFoundException :O413#8
Pp }Z"
("userNotExist"); 9;LjM ~Ct
page = PageUtil.createPage(page, totalRecords); _fS\p|W(E
List users = userDAO.getUserByPage(page); =W7-;&
returnnew Result(page, users); gfK_g)'2U
} +\Vw:~e
~+1mH
} h"ZIh= j@
`R2Iw
I&
?+EAp"{j
=J1V?x=l@
pK-tj
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 }ex4dhx2M
x[lIib1s
询,接下来编写UserDAO的代码: _6fy'%J=U
3. UserDAO 和 UserDAOImpl: ?w(hPUd!2
java代码: D\5+2 G
\'Ca1[y@B
sAc1t`
/*Created on 2005-7-15*/ R*pPUw\yn
package com.adt.dao; kFE9}0-
i@+m<YS:2>
import java.util.List; )tBz=hy#
_p8u
&TZ
import org.flyware.util.page.Page; 0s-K oz
.T7CMkYt
import net.sf.hibernate.HibernateException; zd%f5L('
iYB c4'X
/** FQ0&{ulb
* @author Joa QD0x^v8
*/ KWo Ps%G
publicinterface UserDAO extends BaseDAO { R{c~jjd
5,,'hAq_
publicList getUserByName(String name)throws !@lx|=#
a!bW^?PcK
HibernateException; 6MM\nIU)/
BR|0uJ.M
publicint getUserCount()throws HibernateException; ].rKfv:
5 <k)tF%
publicList getUserByPage(Page page)throws w\i]z1
C')KZ|JIC
HibernateException; iT&4;W=72~
GcN}I=4|
} iA{q$>{8
O>~@>/#
Q>4NUq
2&*#k
%ud-3u52M8
java代码: W#U|;@"
9]+zZP_#
lwfS$7^P
/*Created on 2005-7-15*/ 4*Hzys[{
package com.adt.dao.impl; +JYb)rn$^
tRI<K
import java.util.List; "y~*1kBu
q`mxN!1[
import org.flyware.util.page.Page; 2'=)ese
eV!(a8
import net.sf.hibernate.HibernateException; MH)V=xU|)
import net.sf.hibernate.Query; Fy\q>(v.
n@tt.n!{l
import com.adt.dao.UserDAO; xGyl7$J
*bo| F%NAz
/** +pgHCzwJE
* @author Joa ^[SW07o~
*/ aPlEM_escS
public class UserDAOImpl extends BaseDAOHibernateImpl }O+xs3Uv
iPl,KjGk
implements UserDAO { <xSh13<
&-FG}|*4M
/* (non-Javadoc) =c\(]xX
* @see com.adt.dao.UserDAO#getUserByName f|(9+~K/7&
kntY2FM
(java.lang.String) J>#hu3&UOQ
*/ ~x(|'`
publicList getUserByName(String name)throws iLv
-*%%
3r#['UmT
HibernateException { :%9R&p:'ar
String querySentence = "FROM user in class P7W|e~]Yq
?,7!kTRH
com.adt.po.User WHERE user.name=:name"; Es#:0KH].v
Query query = getSession().createQuery ]v}W9{sY
vfn[&WN]
(querySentence); FVkl#Qy~
query.setParameter("name", name); 5uG^`H@X
return query.list(); NsYEBT7f
} P9m
a$?d_BX
/* (non-Javadoc) z\<,}x}V
* @see com.adt.dao.UserDAO#getUserCount() ma-GvWD2
*/ Lk]|;F-2i
publicint getUserCount()throws HibernateException { 9h+Hd&=
int count = 0; ,j>FCj>
String querySentence = "SELECT count(*) FROM @7"n X
9=$pV==
user in class com.adt.po.User"; JAKs [@:
Query query = getSession().createQuery l?"^2in.
sg-^ oy*^
(querySentence); /-!Fr:Ox>
count = ((Integer)query.iterate().next O)V;na
&8f/ 6dq
()).intValue(); ~Y
f8,m
return count; l"[.Q>d
} VF11eZ"
:0(^^6Q\
/* (non-Javadoc) 7L/LlO/
* @see com.adt.dao.UserDAO#getUserByPage 3pML+Y|ij
p=UW ^95
(org.flyware.util.page.Page) @TW:6v`
*/ v&G9HiH
publicList getUserByPage(Page page)throws ,&3+w~Ua
Y(`Bc8h
HibernateException { Zs t)S(
String querySentence = "FROM user in class l'[;q '
cQLPgE0
com.adt.po.User"; ~pp<
T
Query query = getSession().createQuery k(tB+k!vH\
3/usgw1
(querySentence); `+(n+QS _
query.setFirstResult(page.getBeginIndex()) ea @
H
.setMaxResults(page.getEveryPage()); 7;@YR
return query.list(); j<)$ [v6
} !nL94:8U
?uc]Wgw"s
} NG3:=
>A]l|#Rz
Uu+ibVM$
a!6r&<s=E
SJ22
至此,一个完整的分页程序完成。前台的只需要调用 cM9>V2:P
<,p$eQ)T%
userManager.listUser(page)即可得到一个Page对象和结果集对象 KXx;~HtO
xcl;~"c*
的综合体,而传入的参数page对象则可以由前台传入,如果用 6(?@B^S>2
g qORE/[
webwork,甚至可以直接在配置文件中指定。 dHOH]x
C$q-WoTM(
下面给出一个webwork调用示例: a}` M[%d7
java代码: 4e\w C
fA?Wf[`x
(&)uWjq
`
/*Created on 2005-6-17*/ p cUccQ
package com.adt.action.user; / QL<>g
cahlYv'
import java.util.List; 'bZw-t!M@
m,hqq%qz
import org.apache.commons.logging.Log; (W"0c?i|]
import org.apache.commons.logging.LogFactory; `_/1zL[
import org.flyware.util.page.Page; o6 NmDv5
N1g;e?T':
import com.adt.bo.Result; k}kwr[
import com.adt.service.UserService; hx%UZ <a
import com.opensymphony.xwork.Action; 0)PZS>
(?uK
/** aH%tD!%,o
* @author Joa Dz.kJ_"Ro
*/ 8KP
publicclass ListUser implementsAction{ uCW}q.@4
0V8G9Gj
privatestaticfinal Log logger = LogFactory.getLog Q$'\_zV
?vD<_5K;I
(ListUser.class); d_:tiHw$
4E!Pxjl 3a
private UserService userService; >~_>.R+{
/;Cx|\
private Page page; N{RHbSa(
nWYfe-zQxg
privateList users; cbou1Ei
uVZm9Sp
/* JKp@fQT *
* (non-Javadoc) ?JRfhJ:j
* j;Lp@~M
* @see com.opensymphony.xwork.Action#execute() biV|W@JM
*/ #Sg/
publicString execute()throwsException{ FDFVhcr
Result result = userService.listUser(page); M>RLS/r>d
page = result.getPage(); 23;\l
users = result.getContent(); Nt<Ac&6
s
return SUCCESS; kz#x6NXj
} m^0*k|9+G
9p02K@wkD
/** A1zV5-E/
* @return Returns the page. o'P[uB/
*/ *"/BD=INv}
public Page getPage(){ w+%p4VkA<r
return page; Y\1& Uk
} r 3T #Nv
fB; o3!y
/** ONcS,oHW
* @return Returns the users. 2qj0iRH#N<
*/ 0j#$Swa
publicList getUsers(){ xr)m8H
return users; 'HvW&~i(
} HwMe^e;
|])Ko08*tE
/** 7V\M)r{q7
* @param page mp]UUpt
* The page to set. #eI`l`}
*/ +(q
r {G?
publicvoid setPage(Page page){ ,qgR+]?({
this.page = page; 6l>016 x
} aJNsJIY+
).C>>1ZC
/** E&W4`{6K4
* @param users .W-=V zWX
* The users to set. OHF:E44k
*/ 79lG~BGE
publicvoid setUsers(List users){ Me,AE^pgL'
this.users = users; /8(t:
} IP1{gMG
Ce3
/** !.{{QwZ
* @param userService i6h0_q8
>
* The userService to set. CBx5:}t
*/ |-AR)Smt
publicvoid setUserService(UserService userService){ ~Oj-W6-+&,
this.userService = userService; +qF,XJ2
} 3o__tU)B
} n-lDE}K9%B
$J:~jY/J
w\.z-6G
CH h6Mnw
vr>Rd{dm
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, dNs<`2m
Cd'SPaR
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 >\!>CuU
}xzbg
么只需要: p7)b@,
java代码: :}w^-I"
QNm.8c$
\?.M1a[
<?xml version="1.0"?> Uefw
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork obIYC
!}uev
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ;,_c1x/F
?jBh=X\]:
1.0.dtd"> ! XNTk]!
9o5_QnGE
<xwork> y {1p#
nxYp9,c"
<package name="user" extends="webwork- $3n@2 N`
<wt9K2,
interceptors"> ~rU{Q>c
(svd~h e2
<!-- The default interceptor stack name Os7 3u#!'
Mj@ 0F
2hy
--> J$<g"z3
<default-interceptor-ref _\xd]~ELj
K_~SJbl
name="myDefaultWebStack"/> [R[Suf
F{aM6I
<action name="listUser" vV9q5Bj:
YVLaO*(f
class="com.adt.action.user.ListUser"> ?_c*(2i&^
<param t[L'}ig!q
wq&TU'O
name="page.everyPage">10</param> KEj-y+
<result Z)zmT%t
[HhdeLOX
name="success">/user/user_list.jsp</result> U~8 oE_+
</action> 7[ra#>e8'
X[c8P7
</package> mI~k@ !3
)TcW.d6
</xwork> $r=Ud >
`5Qo*qx
Q:B :
@v,qfT*k7
MoP0qNk
sj @'C@oK
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 V<!E9/4rS
/\9X0a2h|E
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。 l;g8_uyjv7
aTy&"
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 f&ym'S
!>+Na~eN
V+l>wMeo
=r:-CRq(
cy6P=k*
我写的一个用于分页的类,用了泛型了,hoho ou@ P#:<B
z_J"Qk
java代码: d98ZC+q
\/9uS.Kw
DjjG?(1
package com.intokr.util; s],+]<qX
k w!1]N
import java.util.List; 0: (@Y
Q
pY: L
/** $fY4amX6Z
* 用于分页的类<br> rX#}2
* 可以用于传递查询的结果也可以用于传送查询的参数<br> 5sq#bvfJ o
* LPk85E
* @version 0.01 @`ttyI^1f
* @author cheng *5#Y[c
*/ B/Lx,
public class Paginator<E> { _6
~/`_(KP
privateint count = 0; // 总记录数 vxo iPqo
privateint p = 1; // 页编号 /*lSpsBn
privateint num = 20; // 每页的记录数 h^5'i}@u
privateList<E> results = null; // 结果 Ui46p
"rr,P0lgX
/** |!)3[<.
* 结果总数 g9;}?h
*/ NTVdSK7z~H
publicint getCount(){ *r+i=i8{
return count; zKWcDbj
} |T9p#) ec2
}IGr%C(3%
publicvoid setCount(int count){ f[!QR
this.count = count; a-,BBM 8|
} C/+8lA6NV
?K/z`E!xhN
/**
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* 本结果所在的页码,从1开始 fO.gfHI
* s]r"-^eS3
* @return Returns the pageNo. % ;2x.
*/ qf9.S)H1Z
publicint getP(){ #]|9aVrr
return p; ge[+/$(1
} 9 frS!AQ
d*T;RBk
/** CBTa9|57
* if(p<=0) p=1 q7wd9 6G:
* d]k>7.
* @param p |YQ:4'^"
*/ F[c;iM(^
publicvoid setP(int p){ n}yqpW!%n
if(p <= 0) q"A( l
p = 1; ;#!`cgAh
this.p = p; lFD$Mc
} ~'HwNzDQc
^m{kn8
/** !+T+BFw.
* 每页记录数量 %?C{0(Z{
*/ xUzSS@ot^
publicint getNum(){ kO\(6f2|x
return num; JF_\A)<ki
} 5HioxHL
t_WNEZW7f
/** oG5JJpLT
* if(num<1) num=1 PZRpH
*/ 3Cwqy#X#8
publicvoid setNum(int num){ VWmZ|9Ri
if(num < 1) o;\0xuM@
num = 1;
2HMlh.R(C
this.num = num; Srz.-,2 PF
} rBkf @
Q4Q*5>
/** 'j!7
O+7y
* 获得总页数 6pQ#Zg()vp
*/ ^[8e|,U
publicint getPageNum(){ (9$/r/-a
return(count - 1) / num + 1; 8sg8gBt
} .dV o[m;
QKbX^C
/** r%$-F2.p
* 获得本页的开始编号,为 (p-1)*num+1 >)U 7$<&b
*/ v/Z}|dT"
publicint getStart(){ NwuME/C7#
return(p - 1) * num + 1; $d!Sl
a
} 7Z"mVh}
![:S~x1
/** +?(2-RBd
* @return Returns the results. n4ce)N@
*/ <<w $Ur
publicList<E> getResults(){ t[F tIj6
return results; vBQ5-00YY=
} >3X!c"#l
+*d,non6v
public void setResults(List<E> results){ p H?VM&x
this.results = results; RWXj)H)w
} F1)Q#ThF\
,$sq]_t
public String toString(){ Sy'/%[+goJ
StringBuilder buff = new StringBuilder l8%x(N4
iH(
K[F /
(); WUdKj
buff.append("{"); *6q8kQsz^1
buff.append("count:").append(count); \y:
0+s/
buff.append(",p:").append(p); QO7> XHn
buff.append(",nump:").append(num); Yq#I#
2RD
buff.append(",results:").append y^hpmTB3"
lVXgp'!#j
(results); J~DP*}~XK
buff.append("}"); 7~eo^/PbS
return buff.toString(); -^$CGRE6A
} bP Er+?fu
]<4Yor}t{;
} /[GOs*{zB
usR19 _E-
z>&Py(