Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 t@BhosR-
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 rPJbbV",+^
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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 M >s,I^
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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 M/8EaQs}
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。 ;5aAnvgW
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分页支持类: {gS7pY%_W
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java代码: G5zsId
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package com.javaeye.common.util; SA-r61
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import java.util.List; D{,
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publicclass PaginationSupport { zCpXF<_C
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publicfinalstaticint PAGESIZE = 30; OjY#xO+'
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privateint pageSize = PAGESIZE; /m*+N9)
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privateList items; Q-$EBNz
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privateint totalCount; !K_ ke h
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privateint[] indexes = newint[0]; EY.Z.gMZI(
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privateint startIndex = 0; |(UkI?V
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public PaginationSupport(List items, int fGDjX!3-S
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totalCount){ H=>;Mj
setPageSize(PAGESIZE); Xx=c'j<
setTotalCount(totalCount); :|E-Dx4F6H
setItems(items); P}$DCD<$U
setStartIndex(0); ZklZU,\!|v
} %0^taA
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public PaginationSupport(List items, int v.e~m2u_F
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totalCount, int startIndex){ x[eho,6)
setPageSize(PAGESIZE); 3h>56{P
setTotalCount(totalCount); :~dI2e\:
setItems(items); + |d[q?
setStartIndex(startIndex); p#fV|2'
} K6;
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public PaginationSupport(List items, int g{$F;qbkO
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totalCount, int pageSize, int startIndex){ <+${gu?^
setPageSize(pageSize); @m(ja@YC
setTotalCount(totalCount); ;kiL`K
setItems(items); 5oR/Q|^
setStartIndex(startIndex); hS 7o=G[
} KZt4 dr
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publicList getItems(){ [(4s\c
return items; '6W|,
} ,aQ{
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publicvoid setItems(List items){ vB T]a
this.items = items; w%Tjn^ d
} >z1q\cz
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publicint getPageSize(){ d(8X?k.S
return pageSize; Y1h)0_0
} x5)YZ~5
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publicvoid setPageSize(int pageSize){ h oL"K
this.pageSize = pageSize; CYWL@<p,
}
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publicint getTotalCount(){ >YW_}kd
return totalCount; y72=d?]W
} &^!vi2$5}
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publicvoid setTotalCount(int totalCount){ ZpTT9{PT=:
if(totalCount > 0){ F8%.-.l)
this.totalCount = totalCount; 2W 9N-t21
int count = totalCount / fu6Ir,
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pageSize; 5t&;>-A'?'
if(totalCount % pageSize > 0) l^*'W(%
count++; gx)!0n;
indexes = newint[count]; r @
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for(int i = 0; i < count; i++){ ^u[n!R\
indexes = pageSize * PQFr4EY?i
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i; o?l9$"\sqb
} Gh #$[5&`
}else{ )cd5iE:FO
this.totalCount = 0; JVgV,4 1
} BYBf`F)4
} Q-M"+ HO
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publicint[] getIndexes(){ W8R"X~!V
return indexes; #.kDin~!
} )$_b?
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publicvoid setIndexes(int[] indexes){ _9Zwg+oO[
this.indexes = indexes; +vh 4I
} :_y}8am;H~
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publicint getStartIndex(){ ySk'#\d
return startIndex; xmI!N0eta
} O0VbKW0h3
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publicvoid setStartIndex(int startIndex){ }JePEmj
if(totalCount <= 0) (s2ke
this.startIndex = 0; c0%.GcF0{
elseif(startIndex >= totalCount) W%bzA11l
this.startIndex = indexes ClvqI"Rd
L)`SNN\ipR
[indexes.length - 1]; wZ_k]{J
elseif(startIndex < 0) QC+K:jL
this.startIndex = 0; eJ3w}"?9s
else{ `x0GT\O2-
this.startIndex = indexes hH|moj]
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[startIndex / pageSize]; %3r`EIB6
} D[5Qd)PIL
} KDODUohC
a*4l!-7
publicint getNextIndex(){ 2MapB*
int nextIndex = getStartIndex() + n%J{Tcn6
bm+
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pageSize; E0Y>2HOuL
if(nextIndex >= totalCount) xy$agt>j>
return getStartIndex(); =83FCq"
else gISG<!+X^
return nextIndex; "DniDA
} <FfdOK_
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publicint getPreviousIndex(){ XAb!hc
int previousIndex = getStartIndex() - >)sB#<e
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pageSize; 9J0JSy
if(previousIndex < 0) dfss_}R
return0; 4._U
else pW>?%ft.
return previousIndex; cR0OJ'w
} ph;ds+b
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} ).BZPyV<
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抽象业务类 kDz!v?Z2+B
java代码: xElHYh(\
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/** (")IU{>c6
* Created on 2005-7-12 9mEt**s
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*/ ^s_BY+#
package com.javaeye.common.business; ?%RN? O(
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import java.io.Serializable; NR*s7>
import java.util.List; .D~ZE94@
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import org.hibernate.Criteria; aWe?n;
import org.hibernate.HibernateException; EPE9HvN
import org.hibernate.Session; [-*1M4D9
import org.hibernate.criterion.DetachedCriteria; ?'@tx4#v\2
import org.hibernate.criterion.Projections; d1"%sI
import 3j]P\T
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org.springframework.orm.hibernate3.HibernateCallback; l20fA-T
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import Y]ZNAR
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org.springframework.orm.hibernate3.support.HibernateDaoS ac-R q.GQY
%SHjJCS3
upport; yt+"\d
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import com.javaeye.common.util.PaginationSupport; <d$L}uQwg
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public abstract class AbstractManager extends ?-y!FD}m&
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HibernateDaoSupport { OqaVp/,
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privateboolean cacheQueries = false; 1Rrl59}5
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privateString queryCacheRegion; o]#M8)=
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publicvoid setCacheQueries(boolean E7_)P>aS5
: " ([i"
cacheQueries){ Vz"Ja
this.cacheQueries = cacheQueries; K,VN?t<h
}
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publicvoid setQueryCacheRegion(String AS}
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queryCacheRegion){ 1qR[&=/
this.queryCacheRegion = )<.BN
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queryCacheRegion; ~F</s.
} 'pJ46"D@m
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publicvoid save(finalObject entity){ `qNhB\
getHibernateTemplate().save(entity); lcv&/ A
} RY>BP[h
@+9x8*~S'
publicvoid persist(finalObject entity){ yEaim~
getHibernateTemplate().save(entity); E!~Ok
} "1<>c/h
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publicvoid update(finalObject entity){ E5#Dn.!~
getHibernateTemplate().update(entity); %[x oA)0!
} d:U2b"k=/u
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publicvoid delete(finalObject entity){ C&&*6E5
getHibernateTemplate().delete(entity); "kE$2Kg
} 3Ishe"
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publicObject load(finalClass entity, Ddf7wszW
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finalSerializable id){ vS! TnmF
return getHibernateTemplate().load :V(+]<
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(entity, id); 4QK~qAi
} w3l+BUn:X
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publicObject get(finalClass entity, 3$.R=MQ7
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finalSerializable id){ P,$|.pd'
return getHibernateTemplate().get k *a?Ey$
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(entity, id); N W/RQ(
} PRs[!EB6
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publicList findAll(finalClass entity){ ,?OV39h
return getHibernateTemplate().find("from k/"^W.B aj
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" + entity.getName()); .pP{;:Avpn
} mSw$?
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publicList findByNamedQuery(finalString Fq]ht*
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namedQuery){ Cr!}qZq
return getHibernateTemplate FC' v= *
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().findByNamedQuery(namedQuery); nLA8Hy"8z
} %n^jho5
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publicList findByNamedQuery(finalString query, %0>DjzYt
$ BEIG@qG
finalObject parameter){ {,Y?+F
return getHibernateTemplate 2:31J4t-<
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().findByNamedQuery(query, parameter); sH//*y
} &rTOJ1)V}
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publicList findByNamedQuery(finalString query, To x{Sk3L
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finalObject[] parameters){ QKj-"y[
return getHibernateTemplate `zr%+
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().findByNamedQuery(query, parameters); mkA1Sh{hX>
} RXMzwk
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publicList find(finalString query){ eXHk6[%[
return getHibernateTemplate().find +=XDNSw
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(query); xQ4'$rL1d
} ^)r^k8y'
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publicList find(finalString query, finalObject [fN?=,8
"pb$[*_@$
parameter){ YbMeSU/sX
return getHibernateTemplate().find _\HMF
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(query, parameter); $=7'Cm?
} 4LO U[D
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public PaginationSupport findPageByCriteria Pj4WWK X
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(final DetachedCriteria detachedCriteria){ *z2G(Uac
return findPageByCriteria bCM&Fe0GM
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); bITc9Hqc
} N5 BC<pu
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public PaginationSupport findPageByCriteria
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*
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(final DetachedCriteria detachedCriteria, finalint f0uzoeL<%
R)>/P{A-P
startIndex){ o80"ZU|=
return findPageByCriteria MYQZqlV
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(detachedCriteria, PaginationSupport.PAGESIZE, 41c]o<!=)j
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startIndex); I~LN)hqd o
} P@gVzx)M
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public PaginationSupport findPageByCriteria XIM!]
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(final DetachedCriteria detachedCriteria, finalint L* k[Vc
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pageSize, ]0`*gKA
finalint startIndex){ R{s&6
return(PaginationSupport) "62vwWrwO
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getHibernateTemplate().execute(new HibernateCallback(){ AlW0GK=N-p
publicObject doInHibernate V SJGp`
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(Session session)throws HibernateException { Nm{\?
Criteria criteria = . ZuRH_pI
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detachedCriteria.getExecutableCriteria(session); Ls8@@b,t2
int totalCount = )ZxDfRjL
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((Integer) criteria.setProjection(Projections.rowCount 72hN%l
d|GQZAEJEt
()).uniqueResult()).intValue(); (w31W[V'#
criteria.setProjection Gp0H[-oF
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(null); <eU1E}BDQ
List items = \Tf$i(0q
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criteria.setFirstResult(startIndex).setMaxResults i$~2pr
N=1zhI:VaQ
(pageSize).list(); AJk0jh\.j%
PaginationSupport ps = P5u
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ql
new PaginationSupport(items, totalCount, pageSize, )tH.P:
1~,
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startIndex); +_.k\CRms
return ps; %4F
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} 4CO"> :
}, true); _lWC)bv`
} [E9V#J89
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public List findAllByCriteria(final m5!~PG:_
^/nj2"
DetachedCriteria detachedCriteria){ ^*CvKCS
return(List) getHibernateTemplate DuESLMhz
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().execute(new HibernateCallback(){ }6;K+INT
publicObject doInHibernate
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(Session session)throws HibernateException { N?xZ]?T
Criteria criteria = 9g*O;0 uz
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detachedCriteria.getExecutableCriteria(session); $]V,H"
return criteria.list(); PUt\^ke
} C$"N)6%q
}, true); Y(aEp_kV
} !+sC'/
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public int getCountByCriteria(final "r!>p\.0O
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DetachedCriteria detachedCriteria){ nkI+"$Rz0
Integer count = (Integer) _n6ge*,E
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getHibernateTemplate().execute(new HibernateCallback(){
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publicObject doInHibernate o!R.QI^2VT
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(Session session)throws HibernateException { r[doN{%
Criteria criteria = 75@!j[QL<
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detachedCriteria.getExecutableCriteria(session); #'poDX?
return z\S#P|;
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criteria.setProjection(Projections.rowCount /_WAF90R?
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()).uniqueResult(); %bu$t,
} C%2BDj
}, true); _?]0b7X
return count.intValue(); %7w=; ]ym
} w=NM==cLj
} " ^v/Y
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用户在web层构造查询条件detachedCriteria,和可选的 ;rgg O0Y
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 |j 9d.M
<z'Pj7c[
PaginationSupport的实例ps。 sj9j47y
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ps.getItems()得到已分页好的结果集 ^T?zR7r
ps.getIndexes()得到分页索引的数组 f ZEyXb
ps.getTotalCount()得到总结果数 A-n@:` n~
ps.getStartIndex()当前分页索引 7+N0$0w%r
ps.getNextIndex()下一页索引 lu_kir~
ps.getPreviousIndex()上一页索引 gxKL
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 /)%$xi
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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 gGaA;YW1
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一下代码重构了。 ZVelKI8>
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我把原本我的做法也提供出来供大家讨论吧: lfJvN
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首先,为了实现分页查询,我封装了一个Page类: 8+*
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java代码: v}cTS@0
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/*Created on 2005-4-14*/ !W\za0p
package org.flyware.util.page; o+],L_Ab
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/** |o@xWs@m
* @author Joa Ub,5~I+`
* ,`pUz[wl
*/ n 3eLIA{
publicclass Page { ~=P#7l\o1
<r>1W~bp.q
/** imply if the page has previous page */ \CU-a`n
privateboolean hasPrePage;
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/** imply if the page has next page */ &Z3u(Eb
privateboolean hasNextPage; =x
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/** the number of every page */ HZawB25{
privateint everyPage; Y5ZBP?P
3wYhDxY1
/** the total page number */ g[c_rty
privateint totalPage; |j2$G~B6
7DZZdH$Fm
/** the number of current page */ YHp]O+c
privateint currentPage; XLgp.w;
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/** the begin index of the records by the current .A Dik}o
*^3&Y@
query */ JBI> D1`"
privateint beginIndex; ^XgBkC~
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/** The default constructor */ Fv} Uq\v[
public Page(){ @$7'{*
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} r}\m%(i
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{
/** construct the page by everyPage ]as+gZ8
* @param everyPage C JYpgSr
* */ WHy
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public Page(int everyPage){ shZEE2Dr
this.everyPage = everyPage; gWIb"l
} Im!fZ g
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/** The whole constructor */ J1u&Ga
public Page(boolean hasPrePage, boolean hasNextPage, 1YtbV3
l9Av@|
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int everyPage, int totalPage, ?:Sqh1-z
int currentPage, int beginIndex){ [BTOs4f
this.hasPrePage = hasPrePage; "Ng%"Nz
this.hasNextPage = hasNextPage; oFi_
op
this.everyPage = everyPage; D~zk2
this.totalPage = totalPage; gQYs,
this.currentPage = currentPage; /tG[pg{[
this.beginIndex = beginIndex; x+bC\,q
} @@3%lr71
w }=LC#le
/** pf`vH`r
* @return XS(Q)\"
* Returns the beginIndex. .)c+gyaQ
*/ M^&^g
publicint getBeginIndex(){ 2{xf{)hO?
return beginIndex; sh/4ui{
} !BjJ5m
B'-n
^';
/** 8\S$iGd
* @param beginIndex s^"*]9B"
* The beginIndex to set. zXW)v/
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*/ &a'mh
publicvoid setBeginIndex(int beginIndex){ j"
5 +"j
this.beginIndex = beginIndex; 0TqIRUz "C
} em9nuXG
@M*oq2U;
/** f;%=S:3
* @return 3z0%uY[e
* Returns the currentPage. nC}Y+_wo0
*/ G.:QA}FE'
publicint getCurrentPage(){ +F92_a4
return currentPage; n
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} ROJ=ZYof
cKB1o0JsYJ
/** ckkm}|&m
* @param currentPage ID~}pEQ
* The currentPage to set. )@],0yL
*/ f<;eNN
publicvoid setCurrentPage(int currentPage){ Oh3A?!y#
this.currentPage = currentPage; x3l~k Z(
} qm6 X5T
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/** iBk1QRdn
* @return #'5{
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* Returns the everyPage. 629ogJo8
*/ &3|l4R\
publicint getEveryPage(){ (z:qj/|
return everyPage; wln"g,ct
} /], 9N
+yxL}=4s
/** +W"DN5UV
* @param everyPage BUUc9&f3o
* The everyPage to set. =@P]eK/
*/ I&f!>y?,Z
publicvoid setEveryPage(int everyPage){ Eih6?Lpu
this.everyPage = everyPage; PU-L,]K
} '3=@UBs
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/** zym6b@+jN
* @return g'NR\<6A
* Returns the hasNextPage. l\37/Z
*/ MxqIB(5k
publicboolean getHasNextPage(){ y9~:[ jB
return hasNextPage; @!*I
mNMI
} 0.&-1pw
;!B,P-Z"g
/** bb}Fu/S
* @param hasNextPage _2WW0
* The hasNextPage to set. A$n:
*/ <m> m"|G
publicvoid setHasNextPage(boolean hasNextPage){ !
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this.hasNextPage = hasNextPage; ;( (|0Xa
} \s6VOR/
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/** L]E.TvM1*
* @return oxug
* Returns the hasPrePage. L|p+;ex
*/ EUbyQL
publicboolean getHasPrePage(){ P1&Irwb`
return hasPrePage; O f]/tdPp
} sZ0)f!aH:_
47)\\n_\z
/** A&V'WahC@I
* @param hasPrePage _FCg5F2U
* The hasPrePage to set. ~En]sj
*/ ~ E n'X4
publicvoid setHasPrePage(boolean hasPrePage){ U2
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this.hasPrePage = hasPrePage; QTU$mC]
} 8{ )N%r
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/** -YS9u[
* @return Returns the totalPage. :464~tHI[`
* [*g'Y;W
*/ _e "
publicint getTotalPage(){ '26
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return totalPage; !1#=j;N`
} \eXuNv_
q!WiX|P
/** kR<\iT0j
* @param totalPage jP.dQj^j&
* The totalPage to set. G[]h1f!
*/ v)~!HCG
publicvoid setTotalPage(int totalPage){ 2BO"mc<#$
this.totalPage = totalPage; #Eqx Eo;
} 6M[OEI5
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} s14ot80)
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X$=/H 6R5Z
]+Z,HY@;-
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 >6|Xvtf
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个PageUtil,负责对Page对象进行构造: ZQyX zERp
java代码: zor
6%MM)Vj+u
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/*Created on 2005-4-14*/ n`D-?]*
package org.flyware.util.page; m,Mg
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import org.apache.commons.logging.Log; _Nf%x1m5s
import org.apache.commons.logging.LogFactory; =(Y+u
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/** 0y%s\,PsT
* @author Joa S~B{G T\M
* Zbf~E {
*/ ,Y@4d79
publicclass PageUtil { IO"q4(&;P4
yY!@FGsA
privatestaticfinal Log logger = LogFactory.getLog o4,9jk$
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(PageUtil.class); 'JJ :
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/** A`V:r2hnb
* Use the origin page to create a new page ~n%]u! 6
* @param page Q
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* @param totalRecords 4{%-r[C9k
* @return $Zj3#l:rK
*/ @eP(j@(^
publicstatic Page createPage(Page page, int " t,ZO
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totalRecords){ @DlN;r?Cv
return createPage(page.getEveryPage(), rEjEz+wu
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page.getCurrentPage(), totalRecords); JTTI`b2l_
} e09QaY
"sed{?
/** X\5EF7:S
* the basic page utils not including exception 0ej*0"Mq
=-!B4G$
handler 8<
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* @param everyPage >[g.8'hI
* @param currentPage nX<yB9bXDg
* @param totalRecords Ll`nO;h
* @return page \F<C$cys\
*/ Wv30;7~
publicstatic Page createPage(int everyPage, int nbBox,zW
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currentPage, int totalRecords){ +u3vKzD
everyPage = getEveryPage(everyPage); +XAM2uN5_.
currentPage = getCurrentPage(currentPage); ~/!jKH7`j
int beginIndex = getBeginIndex(everyPage, k"+/DK,:
B
\.05<
currentPage); $SU<KNMZ
int totalPage = getTotalPage(everyPage, :!fU+2$`^(
3*e )D/lm
totalRecords); wdRk+
boolean hasNextPage = hasNextPage(currentPage, >viLvDng
G4"n`89LK
totalPage); Se[>z(
boolean hasPrePage = hasPrePage(currentPage); SA~oGgk=P
L/,M@1@R
returnnew Page(hasPrePage, hasNextPage, Kk>va->R
everyPage, totalPage, #^w8Y'{?
currentPage, =!=DISPo
D;Y2yc[v
beginIndex); =9A!5
} BWzo|isv
GX N:=
privatestaticint getEveryPage(int everyPage){ Z
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return everyPage == 0 ? 10 : everyPage; >n5Kz]]%
} l'?(4N
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privatestaticint getCurrentPage(int currentPage){ )Hqn
return currentPage == 0 ? 1 : currentPage; P]4@|u;=6[
} YGZa##i
!uhh_3RH
privatestaticint getBeginIndex(int everyPage, int &izk$~
8zpTCae^=7
currentPage){ nu6v@<<F>
return(currentPage - 1) * everyPage; $
3R5p
} ]F4|@+\9
Y~UWUF%aK
privatestaticint getTotalPage(int everyPage, int nW ]T-!
8CRwHDB
totalRecords){ FZfhiIf
int totalPage = 0; dEfP272M
[UB]vPXm$
if(totalRecords % everyPage == 0) M"8?XD%
totalPage = totalRecords / everyPage; / 16 r_l
else cFoeyI# v
totalPage = totalRecords / everyPage + 1 ; bJL ,pe+u
/%P,y+<}iG
return totalPage; ,772$7x
} %D[6;PT
w=ZK=@
privatestaticboolean hasPrePage(int currentPage){ 5-"aK~@+
return currentPage == 1 ? false : true; Bacmrf
} n;r
W
HG)h,&nc-
privatestaticboolean hasNextPage(int currentPage, 8b $e)
1Pd2%
int totalPage){ l6T5]$
return currentPage == totalPage || totalPage == ?8$h%Ov-
@eRv`O"
0 ? false : true; |@dY[VK>
} (E \lLlN
S~{}jvc
/?:q9Wy
} sB<y(}u
5I0j>{U&
<#e!kWGR?
U
zMIm
*YWk.
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 eX o@3/
ksQw|>K
面对一个具体的业务逻辑:分页查询出User,每页10个结果。具体 SoB6F9
34qfP{9!N
做法如下: !p3vnOX6
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 fUB+9G(Bx
Kk/cI6`W
的信息,和一个结果集List: 't3nh
java代码: <s5s<q2
h\*I*I8C
}z_7?dn/
/*Created on 2005-6-13*/ KOD%>+vG$
package com.adt.bo; Wq*W+7=.
FMAt6HfU
import java.util.List; n#)kvr
jn>RE
import org.flyware.util.page.Page; 0zXF{5Up
ljjnqQ%
/** >>0c)uC|W
* @author Joa ,kE"M1W
*/ CDWchY
publicclass Result { 3mXRLx=0>
oY7 eVu z
private Page page; 3!u:*ibt
+JY]J89
private List content; xBAASy
e",0Er FT
/** x$24Nc1a'
* The default constructor vkW]?::Cfd
*/ VY "i>Ae
public Result(){ 79>_aD9
super(); GD
}i=TK
} x: 2 o$+v3
.$"69[1H
/** \rmge4`4
* The constructor using fields 2-gI@8NPI
* ;Y`k-R:E6A
* @param page X8(WsN
* @param content mjbV^^>
*/ Y> PC>
public Result(Page page, List content){ IJofbuzw:
this.page = page; Nrk/_0^
this.content = content; Eb9{
} hB-<GGcO <
9d&}CZr
/** b "5WsJ:'#
* @return Returns the content. `Qo}4nuRs
*/ 4AuJ1Z
publicList getContent(){ <k-hRs2d
return content; W>rx:O+
} U,GY']J
TAZ+2S# #7
/** Dhp|%_>
* @return Returns the page. pc/]t^]p
*/ Q#*Pjl
public Page getPage(){ $rz'Ybs
return page; hOIk6}r4X
} )n1 7}Qm`V
7|q _JdKoU
/** O@? *5
* @param content - x]gp5
* The content to set. ^0T[V-PgiD
*/ \UBQ:+3
public void setContent(List content){ '@eH)wh@m)
this.content = content; Y(P<9m:
} T'e
p&tNY
KVCj06}j
/** gD/% l[
* @param page 6O'6,%#
* The page to set. cY[qX/0~
*/ ~QE- $;
publicvoid setPage(Page page){ :*s+X$x,<
this.page = page; kK$*,]iCp
} y,=TB[d#
} *p7_rY
\x+ "1
ajALca4
{A MoE+U
M]M(E) *5
2. 编写业务逻辑接口,并实现它(UserManager, wT-@v,$
rgXD>yu(
UserManagerImpl) K^+}__;]
java代码: q.NvwJ
,N`D{H"F
M[,G#GO
/*Created on 2005-7-15*/ z+6%Ya&ls
package com.adt.service; DU1\ K
Gu@Znh-D
import net.sf.hibernate.HibernateException; bdkxCt
1PjqXgN5p
import org.flyware.util.page.Page; Blnc y
uQtwh08i
import com.adt.bo.Result; mY,t]#^m7
}?XNA.Wz
/** n0CS=
* @author Joa ?tFsSU
*/ Z7Xic5PI{4
publicinterface UserManager { eFdN"8EW
WHvU|rJ
public Result listUser(Page page)throws L% ?3VW
p) ea1j>N
HibernateException; TkSeDP
(k&r^V/=
} 7T}r]C.
o!ycVY$yW
)NCkq~M
RTRi{p
q X>\*@
java代码: {Qr0pjE7R
[p[C45d=<
vQIN#;m4
/*Created on 2005-7-15*/ LX_{39?<{
package com.adt.service.impl; IYk^eG:;
K5SP8<.
import java.util.List; ?^H1X-;
Jdp@3mP
import net.sf.hibernate.HibernateException; o:"^@3
k=):>}
import org.flyware.util.page.Page; ?sm@lDZ\
import org.flyware.util.page.PageUtil; S2*ER
auT'ATW7i
import com.adt.bo.Result; WYNO6Xb#:
import com.adt.dao.UserDAO; kw.IVz<
import com.adt.exception.ObjectNotFoundException; ?\$\YX%/p
import com.adt.service.UserManager; [.`%]Z(
q^k]e{PD
/** Ps_q\R
* @author Joa Z-B b,8
*/ K{x FhdW
publicclass UserManagerImpl implements UserManager { ~^R?H S
C^ hCT
private UserDAO userDAO; DR w;.it2
-*r]9f6x
/** jJDYl( [
* @param userDAO The userDAO to set. s55t>t,g6
*/ @"E{gM@B
publicvoid setUserDAO(UserDAO userDAO){ >hbT'Or@
this.userDAO = userDAO; ^HasT4M+x
} Ee?+IZ H7|
'fkaeFzOl
/* (non-Javadoc) 4]/i0\Vbam
* @see com.adt.service.UserManager#listUser p3YF
=ap6IVR
(org.flyware.util.page.Page) J%n{R60b
*/ SS/t8Y4W
public Result listUser(Page page)throws SJdi*>
bR;Zc
HibernateException, ObjectNotFoundException { C5^eD^[c
int totalRecords = userDAO.getUserCount(); `DPR >dd@
if(totalRecords == 0) ko%B`
throw new ObjectNotFoundException $ZOKB9QccC
&`J?`l X
("userNotExist"); p>@S61
&
[
page = PageUtil.createPage(page, totalRecords); c&JYbq
List users = userDAO.getUserByPage(page); Y?>us
returnnew Result(page, users); A,)G$yT\
} ]
336FgT
"Nn+Zw43
} bG6<=^
+$x;FT&
q
T pvz
^sjL@.'m$N
L!]~J?)
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 pt!Q%rXm
3]9twfF 'J
询,接下来编写UserDAO的代码: Jqt&TqX@s
3. UserDAO 和 UserDAOImpl: >`@yh-'r
java代码: fx783
2iM8V
n_Ka+Y<
/*Created on 2005-7-15*/ ?98]\pI
package com.adt.dao; WZ<kk T
OLdD3OI
import java.util.List; ,t]qe
<15POB
import org.flyware.util.page.Page; *KXg;777
8uO@S*)0
import net.sf.hibernate.HibernateException; qWzzUM1=
/<s$Am
/** I:qfB2tL)O
* @author Joa n6a*|rE
*/ 426)H_wx
publicinterface UserDAO extends BaseDAO { dWI.t1`i
$.z~bmH"D
publicList getUserByName(String name)throws +H K)A%QI
yeCR{{B/'
HibernateException; BI\+NGrB
y ;4h'y>#
publicint getUserCount()throws HibernateException; cc%O35o
7(<49bb.V
publicList getUserByPage(Page page)throws =!#iC?I
4#qjRmt
HibernateException; $pT%7jV}
<}E^r_NvD
} Bn"r;pqWiT
[wM<J$=2
m7XJe[O
a#0GmK
/Jc?;@{
java代码: |m%M$^sZ}
&E{5k{Y
0)8QOTeT
/*Created on 2005-7-15*/ ItTIU
package com.adt.dao.impl; JL9d&7-
lbES9o5
import java.util.List; O^]I>A#d
8dw]i1t<
import org.flyware.util.page.Page; :8_`T$8i4
wjmZ`UMz
import net.sf.hibernate.HibernateException; bw7!MAXd
import net.sf.hibernate.Query; n(Up?_
^/W7Xd(s
import com.adt.dao.UserDAO; ~?}/L'q!b
(/_Q
r2KfC
/** P#H#@:/3
* @author Joa 6Upg\(
*/ gkpNT)
public class UserDAOImpl extends BaseDAOHibernateImpl 0;)6ZU
H&L=WF+x
implements UserDAO { v.1= TBh
2`* %NJ
/* (non-Javadoc) %f;(
* @see com.adt.dao.UserDAO#getUserByName f*~ 4Kv
%uGA+ \b
(java.lang.String) @"s\eL,r
*/ 5Ag>,>kJ6
publicList getUserByName(String name)throws Xl6)&
4[3T%jA
HibernateException { lq@Vb{Z
String querySentence = "FROM user in class AEwb'
4(4JQ(5
com.adt.po.User WHERE user.name=:name"; 8m A6l0
Query query = getSession().createQuery *eXO?6f%s^
^c]Sl
(querySentence); L\og`L)5\
query.setParameter("name", name); B>?Y("E
return query.list(); &Jj> jCg
} E|9LUPcb
.bl0w"c^qq
/* (non-Javadoc) }bznx[4?I
* @see com.adt.dao.UserDAO#getUserCount() L>UYR++<6
*/
A!k}
publicint getUserCount()throws HibernateException { =DxJt7J1
int count = 0; y`Pp"!P"O
String querySentence = "SELECT count(*) FROM ~~1~ _0?e
~+>M,LfK
user in class com.adt.po.User"; wZa;cg.-q
Query query = getSession().createQuery (r[<g*+3
A2&&iL=j/
(querySentence); f
5i`B*/
count = ((Integer)query.iterate().next =zA=D.D2
1MJ]Gh]5
()).intValue(); ID+'$u&
return count; nu0bJ:0aLd
} dr6 dK
Xy*X4JJh^
/* (non-Javadoc) \ b9,>
* @see com.adt.dao.UserDAO#getUserByPage na']{a1K
;(0:6P8I
(org.flyware.util.page.Page) `A
<yDy
*/ UxicqkX
publicList getUserByPage(Page page)throws 24N,Bo
3
Dlj=$25
HibernateException { N/?MsrZw
String querySentence = "FROM user in class HHnabSn}{q
MF\n@lX
com.adt.po.User"; jX&&@zMq
Query query = getSession().createQuery \wRr6-!_
\>=YxB q
(querySentence); J#V`W&\,6
query.setFirstResult(page.getBeginIndex()) w78Ius,
.setMaxResults(page.getEveryPage()); lIjHd#q-C
return query.list(); Aq'%a)Y2
} =cC]8Pz?
cn\& ;55v
} f!$J_dz
>qF KXzI
^YIOS]d>8#
8v^i%Gg
bOz\-=au
至此,一个完整的分页程序完成。前台的只需要调用 LVEVCpp@
<$yer)_J!k
userManager.listUser(page)即可得到一个Page对象和结果集对象 ,IJ Nuu\
Ee|+uQ981>
的综合体,而传入的参数page对象则可以由前台传入,如果用 @&ZTEznbyt
^LU[{HZV
webwork,甚至可以直接在配置文件中指定。 k13/yiv
+~fu-%,k
下面给出一个webwork调用示例: M.8!BB7\8e
java代码: w|nVK9.
EhFhL4Xdn
l.)N
/*Created on 2005-6-17*/ Ba+OoS
package com.adt.action.user; BWPYHWW}E
NUnP'X=J,
import java.util.List; E+1j3Q;
"tj#P
import org.apache.commons.logging.Log; pWx3l5)R
import org.apache.commons.logging.LogFactory; Zj7XmkL
import org.flyware.util.page.Page; ;%Da {
@E>^\!nH
import com.adt.bo.Result; %9D@W*Z
import com.adt.service.UserService; /3TorB~Y
import com.opensymphony.xwork.Action; I@S<D"af
xRY5[=97
/** \QMSka>
* @author Joa 'j3'n0o
*/ wKeqR$
publicclass ListUser implementsAction{
yY| .
3QHZC0AY
privatestaticfinal Log logger = LogFactory.getLog &V:dcJ^Q
]czy8n$+
(ListUser.class); )[K3p{4
;&!dD6N
private UserService userService; #]
GM#.
oPbD9
private Page page; rODKM-7+
\fKE~61
privateList users; Ur-^X(nL
ZkIQ-;wx
/* LuqaGy}>-
* (non-Javadoc) .)3 2WD%
* {;}8Z $
* @see com.opensymphony.xwork.Action#execute() sR9F:
*/ i@J,u
publicString execute()throwsException{ \O:xw-eG
Result result = userService.listUser(page); Vx*q'~4y!|
page = result.getPage(); h^0mjdSp,
users = result.getContent(); 4AM*KI
return SUCCESS; !qpu /
} \Cs<'(=
S }n;..{
/** J9 =gv0
* @return Returns the page. bvx:R ~E$
*/ *Z:PB%d5
public Page getPage(){ "XY?v8*c
return page; +n, BD C;
} qC4-J)8Wk
jwq"B$ap
/** :z\f.+MI
* @return Returns the users. dc>y7$2
*/ itF+6wv~
publicList getUsers(){ _'7/99]4g}
return users; *02( J
} W =zG
g=C<E2'i*
/** E%^28}dN
* @param page yx2.7h3
* The page to set. C P#79=1
*/ eC$v0Gtq
publicvoid setPage(Page page){ S>,I&`yi
this.page = page; &FrB6y
} 9^ r
C'._}\nX
/** RNdnlD#P
* @param users y2R=%EFh6
* The users to set. $P(nh'\
*/ #FB>}:L{h*
publicvoid setUsers(List users){ [!&k?.*;<
this.users = users; A,{D9-%
} xiF%\#N
M: "ci;*$
/** rl%Kn^JJ~
* @param userService i'wF>EBz
* The userService to set. V@S/!h+
*/ !7)ID7d
publicvoid setUserService(UserService userService){ }BJ1#<
this.userService = userService; 42CMRGv
} uC(S`Q[Bg
} hPxI&
:N
`&_k\/
1J"9r7\
pYVy(]1I(3
-YV4
O
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, X=pt}j,QrP
XQOprIJ
U
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 ~It+|X=Kx
k_n{Mss'9
么只需要: dCP Tpm
java代码: s7o*|Xv
#`4^zU)
t4@g;U?o
<?xml version="1.0"?> 6\Vu#r
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork MNqyEc""
f#kevf9zc
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ZYe\"|x,s
]zU<=b@
1.0.dtd"> uS#Cb+*F
K=x1mM+RK
<xwork> IKDjatn
F[=lA"F^
<package name="user" extends="webwork- E$tk1SVo
+~Lzsh"
interceptors"> 3c ^=<i
%
j{R|]SjW2H
<!-- The default interceptor stack name |/^aLj^u
%`T5a<
--> M3@fc,Ch
<default-interceptor-ref 6Y)^)dOi
!*Z)[[
name="myDefaultWebStack"/> m=\eL~h
ev%t5NZ
<action name="listUser" MD4 j~q\g
1IQOl
class="com.adt.action.user.ListUser"> rg^\BUa-W,
<param z%3"d0
= )l: ^+q
name="page.everyPage">10</param> "!Oh#Vf
<result oHXW])[
UUf1T@-
name="success">/user/user_list.jsp</result> D2:a
</action> *7;*@H*jd
(vsk^3R[6
</package> qm8n7Z/
C.)&FW2F_
</xwork> Bb[e[,ah
&9dr+o-(~
y2"S\%7$h
z!C4>,
G\>\VA
`V):V4!j),
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 uxMy1oy
<Mn7`i
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。 &iiK ZZ`_o
y8*@dRrq
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 D2%G.z
/W$y"!^)J1
O|OSE
[{p?BTs
@~#79B"9&
我写的一个用于分页的类,用了泛型了,hoho bOSYr<R&
pL}j
ZTo
java代码: FHNuMdFn
R c:cVK
M |Q
package com.intokr.util; ";?C4%L
EM54
import java.util.List;
wy_;+ 'Y
b|ksMB>)
/** &Wv`AoV
* 用于分页的类<br> "o# )vA`
* 可以用于传递查询的结果也可以用于传送查询的参数<br> :KV,:13`D
* 'x,GI\;?
* @version 0.01 E}b>7L&w
* @author cheng XJlDiBs9=Q
*/ YNgR1:l
public class Paginator<E> { b!5tFX;J
privateint count = 0; // 总记录数 OwiWnS<
privateint p = 1; // 页编号 gvc'
$9%
privateint num = 20; // 每页的记录数 v>y8s&/
privateList<E> results = null; // 结果 @t;O"q'|
Hu9-<upc&
/** sx( l
* 结果总数 z^!A/a[[!
*/ fyg~KF}
publicint getCount(){ snTJe[^d
return count; IJ_'w[k
} Pvg
Ro'4/{}+
publicvoid setCount(int count){ ^I'Lw
this.count = count; )>/j&>%
} ^tg6JB;s
V>>) 7E:Q
/** mWN1Q<vn,l
* 本结果所在的页码,从1开始 i_9Cc$Qh<
* 9B#)h)h(=
* @return Returns the pageNo. CdzkMVH
*/ s9_`Wrg?
publicint getP(){ ndKvJH 4
return p; @u"kX2>Eq
} C?/r}ly<\
C;)Xwm>e
/** c5iormb"#
* if(p<=0) p=1 m.HX2(&\3
* -@ UN]K
* @param p k;K>
,$F
*/ z%}CBTm
publicvoid setP(int p){ ]cLEuE^&
if(p <= 0) ~aqT~TL_
p = 1; {?
K|(C
this.p = p; D,GPn%Wqi
} <r7qq$
zqvRkMWc M
/** vSYunI
* 每页记录数量 @wEKCn|}o
*/ _
r^90
publicint getNum(){ n&YW".iG
return num; 0$f_or9T
} G&%nF4
`u p-m=zA
/** gc,J2B]61
* if(num<1) num=1 y,y/PyN)
*/ 5Aa31"43n
publicvoid setNum(int num){ `uNvFlP
if(num < 1) L.IoGUxD
num = 1; B~V<n&<
this.num = num; 75\RG+kQ
} ~ F?G5cN5
t-eKruj+
/** _#J_$CE#
* 获得总页数 cYq']$]
*/ vR%j#v|s
publicint getPageNum(){ ]5o0
return(count - 1) / num + 1; _A;vSp.`
} IFC%%It5,
0.J1!RIK/
/** {FV,j.D
* 获得本页的开始编号,为 (p-1)*num+1 vB{;N
*/ .-('C> @
publicint getStart(){ k7yv>iN
return(p - 1) * num + 1; }sTH.%
} (E"&UC[
uKR\Xo}
/** so?pA@O
* @return Returns the results. ]ZR{D7.?
*/ P<cMP)+K
publicList<E> getResults(){ ,<0Rf
return results; RI[7M (
} }J+ce
%jbJ6c
public void setResults(List<E> results){ *2 qh3
this.results = results; _S9rF-9G]
} q9W~7
.q5J^/kr
public String toString(){ 54ak<&?
StringBuilder buff = new StringBuilder r3+<r<gs
?Kx6Sf<i
(); 95.qAFB1
buff.append("{"); cW81
buff.append("count:").append(count); R/ALR
buff.append(",p:").append(p); z9k*1:
buff.append(",nump:").append(num); b"ol\&1
#
buff.append(",results:").append r,`Z.A
y'J:?!S,Yu
(results); (xk.NZnF
buff.append("}"); `DgaO-Dg3
return buff.toString(); #Acon7Rp
} (TT3(|v
:DOr!PNA
} o9KyAP$2
bc3|;O
[+hy_Nc$