Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 d\v$%0
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 Y'tq m&}
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据这一功能,我设计了通用的抽象Bean基类和分页类支持,代码来 D2Vb{ %(4.
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 |z.Gh1GCy
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分页支持类: qzuQq94k
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java代码: %4?SY82
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package com.javaeye.common.util; *LY~l
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import java.util.List; uPa/,"p
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publicclass PaginationSupport { h$E\2lsE
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publicfinalstaticint PAGESIZE = 30; Mfnlue](
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privateint pageSize = PAGESIZE; J xA^DH
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privateList items; cpE25
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privateint totalCount; 0_YxZS\
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privateint[] indexes = newint[0]; 9oZ}
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privateint startIndex = 0; AyQS4A.s[
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public PaginationSupport(List items, int tQNk=}VR7r
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totalCount){ @rnp- +kq
setPageSize(PAGESIZE); jxRF" GD
setTotalCount(totalCount); 8@Egy%_
setItems(items); /#S4espE
setStartIndex(0); W&fW5af9
} @4 zi]v
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public PaginationSupport(List items, int D6&mf2'u
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totalCount, int startIndex){ 'hwV
setPageSize(PAGESIZE); U%mkhWn
setTotalCount(totalCount); [}W^4,
setItems(items); ?noETH z)
setStartIndex(startIndex); y3
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} {0NsDi>(2
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public PaginationSupport(List items, int 5~ _eN
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totalCount, int pageSize, int startIndex){ fe&
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setPageSize(pageSize); ikEWY_1Y
setTotalCount(totalCount); g@S@d&9
setItems(items); !Z<mrr;T@
setStartIndex(startIndex); 1g~Dm}m
} m.\ >95!
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publicList getItems(){ t,--V|7-
return items; jMm_A#V>p
} N<#S3B?.
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publicvoid setItems(List items){ }m=tzHB*
this.items = items; p56KS5duI.
} )bB"12Z|8
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publicint getPageSize(){ baUEsg[~V
return pageSize; w0a+8gexi
} {pcf;1^t
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publicvoid setPageSize(int pageSize){ H(5S Kv5
this.pageSize = pageSize; }aHB$}"!
} _~X8/p/Qh
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publicint getTotalCount(){ E%wV
return totalCount; n9<roH
} dXA{+<!!
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publicvoid setTotalCount(int totalCount){ nZ2mEt
if(totalCount > 0){ fWtb mUq
this.totalCount = totalCount; A&NC0K}G!
int count = totalCount / R`Ys;g/!
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pageSize; :wv
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if(totalCount % pageSize > 0) _1w.B8Lyz@
count++; E)&NP}k-P
indexes = newint[count]; !#,-
for(int i = 0; i < count; i++){ 8!`7-
indexes = pageSize * 'Yaf\Hp
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} IEno.i\
}else{ Sah<sb=
this.totalCount = 0; 'NQMZfz
} p?Z+z
} xWenKY,
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publicint[] getIndexes(){ %8Z|/LGg
return indexes;
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} +BtLyQ
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publicvoid setIndexes(int[] indexes){ k=h/i8i2z
this.indexes = indexes; 5p]urfN-f
} WryW3];0OR
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publicint getStartIndex(){ >j(I[_g
return startIndex; Q>SPV8s
} 3<KZ.hr
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publicvoid setStartIndex(int startIndex){ VV0EgfJ
if(totalCount <= 0) %9~kA5Qj
this.startIndex = 0; KV^:sxU
elseif(startIndex >= totalCount) ^-e3=&
this.startIndex = indexes ~WYE"(
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[indexes.length - 1]; PK.h E{R
elseif(startIndex < 0) {|Mxvp*Hg
this.startIndex = 0; xoz*UA.
else{ 0]:*v?
this.startIndex = indexes ;*>QG6Fh
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[startIndex / pageSize]; ~
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} o5*74Mv
} h|c:!VN@
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publicint getNextIndex(){ 2#$}yP~
int nextIndex = getStartIndex() + QN2*]+/h
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pageSize; DiGUxnP
if(nextIndex >= totalCount) dFI.`pB
return getStartIndex(); m&3HFf
else .swgXiRvs
return nextIndex; J#Ne:Aj_
} PoBukOv
}OX>(
publicint getPreviousIndex(){ G(7\<x:
int previousIndex = getStartIndex() - o3TBRn,
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pageSize; (<>Sz(
if(previousIndex < 0) C~
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return0; xdbu|fC
else 3-9J"d!
return previousIndex; -Iruua7b
} 8CnvvMf
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} mTXNHvv
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抽象业务类 654jS!
java代码: e%@[d<Ta\
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/** fdCxMKlu;
* Created on 2005-7-12 <Hr@~<@~
*/ 3*2&Fw!B
package com.javaeye.common.business; {Gb)Et]<
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import java.io.Serializable; zM8/s96h
import java.util.List; ?^G$;X7B
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import org.hibernate.Criteria; ZAnO$pA
import org.hibernate.HibernateException; e u=f-HW]
import org.hibernate.Session; 3$kv%uf{
import org.hibernate.criterion.DetachedCriteria; x9&tlKKxf
import org.hibernate.criterion.Projections; JI[rIL\Ey
import N?U&(@p
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org.springframework.orm.hibernate3.HibernateCallback; 9%)& }KK|
import @=<TA0;LL
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org.springframework.orm.hibernate3.support.HibernateDaoS z5o9\.y({
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upport; p-(ADQS
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import com.javaeye.common.util.PaginationSupport; d@>k\6%j
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public abstract class AbstractManager extends i_ODgc`H
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HibernateDaoSupport { =|{,5="
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privateboolean cacheQueries = false; 2h? r![
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privateString queryCacheRegion; H{tOCYyD
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publicvoid setCacheQueries(boolean -Bwu$$0
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cacheQueries){ L&gEQDPgq|
this.cacheQueries = cacheQueries; k~9Ywf
} W%jX-
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publicvoid setQueryCacheRegion(String @9kk
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queryCacheRegion){ \%4+mgiD
this.queryCacheRegion = :#&U95EC0
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queryCacheRegion; ?=@Q12R)X
} aab4c^Ms=
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publicvoid save(finalObject entity){ G'}_ZUy#
getHibernateTemplate().save(entity); %Ty
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} fdH'z:Xao
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publicvoid persist(finalObject entity){ pt|$bU7
getHibernateTemplate().save(entity); ;Q,).@<C
} |s3HeY+Co
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publicvoid update(finalObject entity){ sxQ ,x/O
getHibernateTemplate().update(entity); 7!yF5+_d
} W 9:{pQG
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publicvoid delete(finalObject entity){ eS# 0-
getHibernateTemplate().delete(entity); 6~Oje>w;
} Vqp.jF1|
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publicObject load(finalClass entity, Ex s _LN
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finalSerializable id){ +fQ$~vr{'
return getHibernateTemplate().load O>):^$-K%
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(entity, id); 90if:mYA
} 2mp>Mn~K^
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publicObject get(finalClass entity, )I
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finalSerializable id){ |`D5XRVbi
return getHibernateTemplate().get Q@.9wEAJ
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(entity, id); ^l2d?v8
} ;@-5lCvC(+
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publicList findAll(finalClass entity){ 9DAwC:<r
return getHibernateTemplate().find("from FEi,^V
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" + entity.getName()); AkQFb2|ir
} ?}Ptb&Vk(
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publicList findByNamedQuery(finalString VKfHN_m*
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namedQuery){ A)a+LW'=u
return getHibernateTemplate 4Jy,IKPp
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().findByNamedQuery(namedQuery); "N:]d*A\
} "=TTsxyM6P
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publicList findByNamedQuery(finalString query, m3!MHe~t
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finalObject parameter){ 8;Bwz RtgT
return getHibernateTemplate `TR9GWU+B
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().findByNamedQuery(query, parameter); w]YyU5rhS
} "&o@%){]
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publicList findByNamedQuery(finalString query, 9@>hm>g.
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finalObject[] parameters){ /%'7sx[p
return getHibernateTemplate Y~?YA/.x
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().findByNamedQuery(query, parameters); \yizIo.Y`
} MZMv.OeYt,
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publicList find(finalString query){ >oYwzK0&
return getHibernateTemplate().find $[;eb,
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(query); L#MxB|fcr
} n8D;6#P^
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publicList find(finalString query, finalObject Bq=](<>>
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parameter){ NW
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return getHibernateTemplate().find
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(query, parameter); EGO@`<"h
} tD482Sb=
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public PaginationSupport findPageByCriteria T $]L 5
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(final DetachedCriteria detachedCriteria){ ptL}F~
return findPageByCriteria 'QS~<^-j"
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); }j@@
} \>k#]4@rp
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public PaginationSupport findPageByCriteria u<r('IW0
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(final DetachedCriteria detachedCriteria, finalint *njB
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startIndex){ Bm>(m{sX>
return findPageByCriteria iEO2Bil]
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(detachedCriteria, PaginationSupport.PAGESIZE, f3|=T8"t
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startIndex); *3oQS"8
} oQB1fs
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public PaginationSupport findPageByCriteria Q%d[U4@
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(final DetachedCriteria detachedCriteria, finalint
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pageSize, X2 kLbe
finalint startIndex){ bTKxv<
return(PaginationSupport) g{{SY5qDj
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getHibernateTemplate().execute(new HibernateCallback(){ nrhpId
publicObject doInHibernate 4tKf
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(Session session)throws HibernateException { hzVO.Q*
Criteria criteria = }/FM#Xh
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detachedCriteria.getExecutableCriteria(session); 1#RA+d(
int totalCount = @&>
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((Integer) criteria.setProjection(Projections.rowCount (~o+pp!
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()).uniqueResult()).intValue(); *Y?]="8c#;
criteria.setProjection f
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(null); YR#1[fe*_
List items = 0M.[) @
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criteria.setFirstResult(startIndex).setMaxResults 8\_,Y
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(pageSize).list(); >qZRIDE5$
PaginationSupport ps = mJqP#Unik
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new PaginationSupport(items, totalCount, pageSize, -p~B
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startIndex); w-/Tb~#E
return ps; -OAH6U9^
} zj4JWUM2
}, true); y['icGU6
} 3".W
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public List findAllByCriteria(final 3N\X{za
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DetachedCriteria detachedCriteria){ .=D6<4#t
return(List) getHibernateTemplate M](U"K?
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().execute(new HibernateCallback(){ !%=k/|#
publicObject doInHibernate RmCR"~
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(Session session)throws HibernateException { Fv
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Criteria criteria = IRY2H#:$
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detachedCriteria.getExecutableCriteria(session); %M:"Ai5:
return criteria.list(); JJO"\^,;~
} nV1,
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}, true); T[J_/DE@
} yK;I<8+>_
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public int getCountByCriteria(final $S/ 8T
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DetachedCriteria detachedCriteria){ uEY5&wX`
Integer count = (Integer) ,;}RIcvQV
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getHibernateTemplate().execute(new HibernateCallback(){ bSzb! hT`
publicObject doInHibernate `WL*Jb
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(Session session)throws HibernateException { F!'"mU<f
Criteria criteria = mZ%\`H+
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detachedCriteria.getExecutableCriteria(session); Pd?YS!+S
return }qg&2M%\
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criteria.setProjection(Projections.rowCount Nq8A vBwo4
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()).uniqueResult(); v4G kf
} uR[i9%=8L(
}, true); R7>@-EG
return count.intValue(); p-_j0zv
} TY}?>t+
} hCrgN?Mz
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用户在web层构造查询条件detachedCriteria,和可选的 :yeTzIz]
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 shRvwE[
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PaginationSupport的实例ps。 ]0O$2 j_ 7
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ps.getItems()得到已分页好的结果集 yO)Qg*r
ps.getIndexes()得到分页索引的数组 -_dgd:or
ps.getTotalCount()得到总结果数 ;DOz92X94
ps.getStartIndex()当前分页索引 TfOZ>uR"g
ps.getNextIndex()下一页索引 0%GWc}o
ps.getPreviousIndex()上一页索引 uB?YJf .T@
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 {_JLmyaerZ
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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 =G`m7!Q)
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一下代码重构了。 r_",E=e
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我把原本我的做法也提供出来供大家讨论吧: T/ov0l_
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首先,为了实现分页查询,我封装了一个Page类: w>eOERZa
java代码: okW3V}/x/z
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/*Created on 2005-4-14*/ ??Lxb% 7R
package org.flyware.util.page; \]D;HR`vo
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/** )8_0 d)
* @author Joa 7g$t$cZby,
* fHiCuF
*/ mTt 9 o9E
publicclass Page { T
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/** imply if the page has previous page */ Zo`^pQS
privateboolean hasPrePage; oj/tim
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/** imply if the page has next page */ GZ%RfKyQ
privateboolean hasNextPage; ETIf x)B-
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/** the number of every page */ )c*~Y=f
privateint everyPage; z t1Q_;
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/** the total page number */ 6 B
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privateint totalPage; X*sF-T$.
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/** the number of current page */ ]loO 5
privateint currentPage; er_aol e
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/** the begin index of the records by the current rtI4W
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query */ {"<Q?yA2y
privateint beginIndex; CNwhH)*
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/** The default constructor */ +$9w[ARN+
public Page(){ }K/[3X=B
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} 'K`)q6m
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/** construct the page by everyPage V3-LVgM%
* @param everyPage j6\{j#q
* */ w-KtxG(
public Page(int everyPage){ QMIQy
this.everyPage = everyPage; _CgD7d
} FvkKM+?F
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/** The whole constructor */ PU8R
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public Page(boolean hasPrePage, boolean hasNextPage, k";;Snk
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int everyPage, int totalPage, 6};Sn/8
int currentPage, int beginIndex){ HdGy$m`
this.hasPrePage = hasPrePage; ev; &$Hc
this.hasNextPage = hasNextPage; O&)Y3 O1
this.everyPage = everyPage; @=9QV3D
this.totalPage = totalPage; W&"FejD
this.currentPage = currentPage; f; 22viE
this.beginIndex = beginIndex; ~6OdPD
} NEN br$,G
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/** .VI2V-Q
* @return fF9vV. }
* Returns the beginIndex. (YR1ML3N
*/ F2u{Wzr_@
publicint getBeginIndex(){ bZ389dSn
return beginIndex; kqyY:J
} Jlzhn#5c-
}/=VnCfU
/** NZl0sX.:
* @param beginIndex ur'A ;B
* The beginIndex to set. GUK/Xiu
*/ ]!f=b\-Av
publicvoid setBeginIndex(int beginIndex){ _ K9jj
this.beginIndex = beginIndex; A_[65'*b
} =.uE(L`]NA
}NUP[%
/** 8T%z{ A1T
* @return old}}>_
* Returns the currentPage. +pE-Yn`YS
*/ O9qEKW)a
publicint getCurrentPage(){ #bGt%*Re p
return currentPage; SDot0`s>
} U zc`,iV$
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/** 8U-}%D<a
* @param currentPage 1|zo-'y
* The currentPage to set. G6I>Ry[2?
*/ SnVnC09y
publicvoid setCurrentPage(int currentPage){ V8c&2rNa
this.currentPage = currentPage; KQEn C`Nz
} U#Ud~Q q
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/** nTLdknh"
* @return +VTMa9d
* Returns the everyPage. ,fL*yn
*/ i |C'_gw`n
publicint getEveryPage(){ @P%&Dha
return everyPage; wL}=$DN
} f#[Fqkmj
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/** d/"e3S1
* @param everyPage 7VR+EV
* The everyPage to set. .~Td/o7
*/ A$
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publicvoid setEveryPage(int everyPage){ vmL0H)q
this.everyPage = everyPage; ba
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} @o_-UsUX
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/** )4DF9 JpD
* @return xvb5-tK
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* Returns the hasNextPage. oas}8A)
*/ f 1]1ZOb
publicboolean getHasNextPage(){ }VyDX14j
return hasNextPage; O[$&]>x]]
} 'sJYt^
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/** ~Z T(@w
* @param hasNextPage 1{_;`V
* The hasNextPage to set. JEj.D=@[
*/ D;m>9{=
publicvoid setHasNextPage(boolean hasNextPage){ |o6B:NH,rg
this.hasNextPage = hasNextPage; 58WL8xu
} ?&"-y)FG
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/** \= i>}Sg
* @return @*!8
* Returns the hasPrePage. 8M!If
*/ NKh 8'=S
publicboolean getHasPrePage(){ U@DIO/C,m`
return hasPrePage; H htAD Y
} %I?uO(
@
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/** @=:( b"Sg
* @param hasPrePage Ub0g{
* The hasPrePage to set. KxqJlben
*/ 8eQ 4[wJY
publicvoid setHasPrePage(boolean hasPrePage){ jo/-'Lf{?
this.hasPrePage = hasPrePage; u m,Zt
} e0qU2
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/** dy`K5lC@
* @return Returns the totalPage. {e,S}:$g4
* 6_rS!X
*/ UhXZ^k3
publicint getTotalPage(){ 94\k++kc
return totalPage; ?o?~Df&
} "1yXOy^2
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/** J1KV?aR
* @param totalPage \= =rdW-
* The totalPage to set. 8 Zhx&
*/ >Ta|#]{
publicvoid setTotalPage(int totalPage){ {L4ta~2/T
this.totalPage = totalPage; ]gx]7
} C,HKao\
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} `2()Vf
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上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 fIWOo >)D
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个PageUtil,负责对Page对象进行构造: 1U^;fqvja
java代码: TldqF BX
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/*Created on 2005-4-14*/ U8m/L^zh
package org.flyware.util.page; W^v3pH-y#
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import org.apache.commons.logging.Log; Bs:INvhYW
import org.apache.commons.logging.LogFactory; f_I6g uDPz
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/** 68
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* @author Joa _=S4H
* ?H3Ls~R
*/ D;*P'%_Z
publicclass PageUtil { L"e8S%UqX
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privatestaticfinal Log logger = LogFactory.getLog `o4alK\
Y- esD'MD
(PageUtil.class); VB=$D|Ll
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/** C+tB$yahO
* Use the origin page to create a new page RE6dN
* @param page ]6#bp,
* @param totalRecords HtFc+%=
* @return wA$ JDf)Vg
*/ jJc:%h$|2
publicstatic Page createPage(Page page, int !g=4\C`mY
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totalRecords){ X"lPXoCN
return createPage(page.getEveryPage(), 0&wbGbg(W
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page.getCurrentPage(), totalRecords); p(vmMWR!
} 8725ET
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/** _3YZz$07
* the basic page utils not including exception jjLx60|{
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handler g4z*6L,u
* @param everyPage `-yo-59E[
* @param currentPage Fp=O:]
* @param totalRecords !79eF)
* @return page -9)H[}.
*/ :Q]P=-Y8
publicstatic Page createPage(int everyPage, int $DS|jnpV
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currentPage, int totalRecords){ Pnl+.?
everyPage = getEveryPage(everyPage); xs?Ska,N
currentPage = getCurrentPage(currentPage); rlMahY"C
int beginIndex = getBeginIndex(everyPage, aq,Ab~V]
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currentPage); v_G1YC7TU
int totalPage = getTotalPage(everyPage, 1xBgb/+
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totalRecords); f
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boolean hasNextPage = hasNextPage(currentPage, rD_\NgVAs
1/\JJ\
totalPage);
}%)]b*3
boolean hasPrePage = hasPrePage(currentPage); V$o]}|
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returnnew Page(hasPrePage, hasNextPage, 9 ^+8b9y
everyPage, totalPage, %7}ibz4iF
currentPage, HAKB@h)
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beginIndex); r&rip^40
} {f1iys'Om
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privatestaticint getEveryPage(int everyPage){ H;w8[ImK
return everyPage == 0 ? 10 : everyPage; FHOF6}if
} w#qE#g %1
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privatestaticint getCurrentPage(int currentPage){ nY M2Vxi0+
return currentPage == 0 ? 1 : currentPage; ){}1u ?
} H6/n
KATu7)e&~^
privatestaticint getBeginIndex(int everyPage, int oU`{6 ~;
2p|ed=ly%
currentPage){ )JA9bR
<
return(currentPage - 1) * everyPage; ^7l+ Ofb3
} z ?L]5m`H
}ebu@)r
privatestaticint getTotalPage(int everyPage, int "rVf{
X:2)C-l?
totalRecords){ &9OnN<mT1
int totalPage = 0; jCp^CNbA
;M<R
e
if(totalRecords % everyPage == 0) T;C0t9Yew
totalPage = totalRecords / everyPage; 'f_[(o+n
else 8{4SaT.-Rm
totalPage = totalRecords / everyPage + 1 ; P1G;JK
_jWGwO
return totalPage; g>*P}r~;^b
}
:q34KP
WJU[+|J
privatestaticboolean hasPrePage(int currentPage){ JavSR1_
return currentPage == 1 ? false : true; N!lQ;o'
} Wj INY
s:zz8oN
privatestaticboolean hasNextPage(int currentPage, 5}Z_A?gy
6<SX%Bc~
int totalPage){ 2 Q}^<^r
return currentPage == totalPage || totalPage == ]5a,%*f+
1fMl8[!JLu
0 ? false : true; XMlcY;W
} b|Sjh;
?v,4seRuz
9.>he+
} 4Ai#$SHLm
Lj2Au_5
~5:-;ZbZ
bIy:~z5
_z6 " C8W
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。 *f-8egt-
]k)h<)nY
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 v43FU3
(|dN6M-.K
做法如下: HDQH7Bs
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 8i~n;AhDs
vYNu=vnM
的信息,和一个结果集List: |2!cPf^8
java代码:
*\# ?)q
WfH4*e
hQ _gOI
/*Created on 2005-6-13*/ _FxQl]@
package com.adt.bo; 5:vy_e&
gJYX
import java.util.List; ?4sF:Y+\
l<-0@(x)
import org.flyware.util.page.Page; ov|/=bzro
WUK{st.z
/** aTFT'(O,
* @author Joa m\eYm;RVj
*/ ~8tb^
publicclass Result { 3:MAdh[w
-p*j9
z
private Page page; N
VBWF
d9pZg=$8
private List content; tdi^e;:?
n-x%<j(Xf
/** 7-j=he/
* The default constructor O m5+j:YM
*/ u&Cu"-%=M
public Result(){ L4!T
super(); \QP1jB
} -_T@kg[0zB
C@OY)!x!
/** ^"{txd?6
* The constructor using fields j-(k`w\
* zC|y" PTw
* @param page (aX6jdvo
* @param content xB|?}uS-
*/ !9g>/9h
public Result(Page page, List content){ ~9JLqN"
this.page = page; HOb0\X
this.content = content; dU.H9\p
} v~KgCLo
}gtkO&
/** @f%q ,:
* @return Returns the content. @ $2xiE.[
*/ aP` V
publicList getContent(){ ]#P>wW
return content; Q|Go7MQZ@k
} <~iA{sY)O
'w`3( ':=
/** &k@r23V7r
* @return Returns the page. |yYu!+U
*/ 2>h.K/pC
public Page getPage(){ n+H);Dg<8
return page; DcX,o*ec!
} B`/p[ U5
,#hx%$f}d
/** BiI`oCX
* @param content {N`<THPP
* The content to set. c~v(bK
*/ F8OE
public void setContent(List content){ 1zWEK]2.R
this.content = content; :GN7JxD#
} +?y9EZB%
yGX"1Fb?;x
/** X.FFBKjf[e
* @param page Y4,LXuQ
* The page to set. CSNfLGA
*/ Uv%?z0F<C
publicvoid setPage(Page page){ qIg^R@
this.page = page; |iGfWJ^+
} ![hVTZ,hyZ
} ;6/dFOZn
D>m!R[!o
qcR"i+b
m6YDyQC
o btXtqew
2. 编写业务逻辑接口,并实现它(UserManager, xq\A TON
Yxd&hr
UserManagerImpl) 6R';[um?q
java代码: d'*:2;)g^
(f>~+-IL
qb?9i-(
/*Created on 2005-7-15*/ rBrJTF:.
package com.adt.service; h?+bW'm
9 ,>u,
import net.sf.hibernate.HibernateException; q<>aZ|r
h+d3 JM
import org.flyware.util.page.Page; A-5'OI
* vW#XDx
import com.adt.bo.Result; V7q-Pfh!y
)Y
9JP@}T
/** MrFi0G7u
* @author Joa 5@< D6>6
*/ Y=tx
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publicinterface UserManager { I+g[
p
}.74w0~0^
public Result listUser(Page page)throws ]q<Zc>OC
3e7P
w`gLl
HibernateException; \&.]!!Q
iz5WWn^
} iES?}K/q
iU9> qJ]
GEQ3r'B|
0
V3`rK
e
QGhX(
java代码: t%Hy#z1W_
\SQ wIM
(OT&:WwW
/*Created on 2005-7-15*/ zcE[wM
package com.adt.service.impl; w;4FN'
\'.#of
import java.util.List; NZ=`iA8)X
8nQjD<-
import net.sf.hibernate.HibernateException; 0VBbSn}Z<
8e*1L:oB!
import org.flyware.util.page.Page; h4lrt
import org.flyware.util.page.PageUtil; ZA
Xw=O5
/R!/)sg
import com.adt.bo.Result; ~.L\f%<
import com.adt.dao.UserDAO; LJ+Qe%|
import com.adt.exception.ObjectNotFoundException; mOE%:xq9-
import com.adt.service.UserManager; Ed +"F{!eQ
^;gwD4(hs
/** @ZTsl ?
* @author Joa W&Pp5KR
*/ ,sln0
publicclass UserManagerImpl implements UserManager { o:8*WCiqrN
ZQ'bB5I
private UserDAO userDAO; r~U/t~V=D
Mz#<Vm4
/** v cZg3:j
* @param userDAO The userDAO to set. :UDT!
5FNO
*/ 2!E@Gbhm5
publicvoid setUserDAO(UserDAO userDAO){ E"[h20`\/
this.userDAO = userDAO; f%JC;Y
} K6X}d,g
I|oS`iLl$
/* (non-Javadoc) l1MVC@'pvP
* @see com.adt.service.UserManager#listUser l\%LT{$e
Vp~c$y+
(org.flyware.util.page.Page) OPP^n-iPr
*/ ">D7wX,.>
public Result listUser(Page page)throws WjVj@oC
mf\eg`'4?
HibernateException, ObjectNotFoundException { GfMCHs
int totalRecords = userDAO.getUserCount(); TqN4OkCm/
if(totalRecords == 0) vk]vtjf&%
throw new ObjectNotFoundException z-X_O32
i6y$P6s
("userNotExist"); @ky<5r*JU(
page = PageUtil.createPage(page, totalRecords); +M/1,&
List users = userDAO.getUserByPage(page); g&oAa;~o
returnnew Result(page, users); ;R
x Rap
} r}]%(D](v
"0edk"hk
}
~.H*"
DpZO$5.Ec+
a][QY1E@?
'|JBA.s|
1{pU:/_W
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 #y:,owo3I
m_pqU(sP
询,接下来编写UserDAO的代码: - IF3'VG
3. UserDAO 和 UserDAOImpl: nnol)|C{5Y
java代码: dqu+-43I|
*c1)x
Y!C8@B$MR3
/*Created on 2005-7-15*/ 4>I >y@^
package com.adt.dao; _I1:|y
A;\1`_i0
import java.util.List; quGvq"Y>
ejjL>'G/|%
import org.flyware.util.page.Page; 1#m'u5L
B=p6pf
import net.sf.hibernate.HibernateException; swGp{wJ
~?#B(t
/**
+91j 1?
* @author Joa VvSe`E*
*/ *eLKD_D`!C
publicinterface UserDAO extends BaseDAO { X@j.$0eK
k6b0&il
publicList getUserByName(String name)throws @V>BG8Y
jF r[T
HibernateException; d%wy@h
bh&Wy<Y
publicint getUserCount()throws HibernateException; 8M,AFZ>F
:psP|7%|
publicList getUserByPage(Page page)throws N">4I)
eGF+@)K1"
HibernateException; >&g^ `
0!fT:Ra
} 1;8%\r[|5^
B2/d%B
Q2(K+!Oe
^/V>^9CZ
!`h^S)$
java代码: >nqCUhS
iS]4F_|vd
jr`;H
/*Created on 2005-7-15*/ U-mZO7y!
package com.adt.dao.impl; YooPHeQ
g;n6hXq4
import java.util.List; "AcC\iq
suF<VJ)&s
import org.flyware.util.page.Page; ](2\w9i%
L)qDtXd4
import net.sf.hibernate.HibernateException; $]`rWSYtv`
import net.sf.hibernate.Query; R|u2ga~
HZJ)q`1E
import com.adt.dao.UserDAO; %UXmWXF4$
C^^AN~ZD
/** r\."=l
* @author Joa ZCC T
*/ , R;k>'.
public class UserDAOImpl extends BaseDAOHibernateImpl A6Vb'Gqv{
;b6h/*;'
implements UserDAO { ALY3en9,
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/* (non-Javadoc)
BV-(`#~:y
* @see com.adt.dao.UserDAO#getUserByName n)t'?7
f'WRszrF
(java.lang.String) ]H$Trf:L
*/ Svl;Ul
publicList getUserByName(String name)throws LuE0Hb"S8
9
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HibernateException { qe<xH#6
String querySentence = "FROM user in class kIwq%c;
&ra2(S45
com.adt.po.User WHERE user.name=:name"; F>lM[Lu#
Query query = getSession().createQuery :6[G;F7s
9pMXjsE
(querySentence); pAtt=R,Ht
query.setParameter("name", name); ]*]#I?&'Hx
return query.list(); =!N,{V_
} "969F(S$
Z(Z$>P&4
/* (non-Javadoc) >.1d1#+b
* @see com.adt.dao.UserDAO#getUserCount() mTU[khEmL=
*/ e,DRQ2AU
publicint getUserCount()throws HibernateException { 5I>a|I!j
int count = 0; dIq*"Ry+~
String querySentence = "SELECT count(*) FROM jb83Y>
K3.z>.F'h
user in class com.adt.po.User"; k@
So l6
Query query = getSession().createQuery `P/87=h
^9zlxs`<d
(querySentence); ZuNUha&a
count = ((Integer)query.iterate().next 9
M90X8
[U@;EeS
()).intValue(); -2qI2Z
return count;
B".3NQ
} 9
K~X+N\
&ev#C%Nu
/* (non-Javadoc) CsX@u#
* @see com.adt.dao.UserDAO#getUserByPage @QfbIP9
#9rCF 3P
(org.flyware.util.page.Page) #B6$r/%
*/ 8'-E>+L
publicList getUserByPage(Page page)throws ql I1<Jx
pqDlg
HibernateException { rKkFflOVO
String querySentence = "FROM user in class :/\KVz'fw}
DCSmEy`.
com.adt.po.User"; otmyI;v 7<
Query query = getSession().createQuery f64}#E|w
4K0Fc^-
(querySentence); ?W\KIp\Kn
query.setFirstResult(page.getBeginIndex()) <~hx ~"c
.setMaxResults(page.getEveryPage()); _+ERX[i
return query.list(); #}+_Hy
} ?.g="{5X
*]>~lO1
} :4x&B^,53
ow4|GLU^;
M Ui#3o\f
9/PX~j9O?
30{+gYA
至此,一个完整的分页程序完成。前台的只需要调用 %*^s%NI
@@5JuI-!
userManager.listUser(page)即可得到一个Page对象和结果集对象 {`+:!X
jL*s(Yq
的综合体,而传入的参数page对象则可以由前台传入,如果用 ;]VLA9dC
bC,SE*F\
webwork,甚至可以直接在配置文件中指定。 +HF*X~},i
Eyh(257
下面给出一个webwork调用示例: I|tn7|*-A[
java代码: S #C;"se
50^CILKo7
A"wso[{
/*Created on 2005-6-17*/ SN5Z@kK
package com.adt.action.user; *qKf!&
=zRjb>
import java.util.List; f!bGH-.r5
mMtva}=*
import org.apache.commons.logging.Log; Q(BM0n)f
import org.apache.commons.logging.LogFactory; $%zM Z
import org.flyware.util.page.Page; BWLeitS/
7!A3PDAe
import com.adt.bo.Result; Q5c13g2(c
import com.adt.service.UserService; X=[`+=
import com.opensymphony.xwork.Action; k8w:8*y'.
,ik\MSS
/** s@K #M
* @author Joa RJE<1!{
*/ c HUj6'neO
publicclass ListUser implementsAction{ Tl
S904'
Z9UNp[0
privatestaticfinal Log logger = LogFactory.getLog +K61-Div
/'L/O;H20
(ListUser.class); X({R+
/H$/s=YU\U
private UserService userService; 4~e6z(
gx=2]~O1(
private Page page; NBO&VYs|
eXCH*vZY
privateList users; f/pr
K~14;
/* XB+Juk&d
* (non-Javadoc) V]|P>>`v9p
* ^fhkWx 4i
* @see com.opensymphony.xwork.Action#execute() .]BJM?9
*/ LLJsBHi-
publicString execute()throwsException{ cxxrvP-
Result result = userService.listUser(page);
'cf8VD
page = result.getPage(); '+iqbcUd,
users = result.getContent(); qdwjg8fo4Z
return SUCCESS; cB4p.iO
} e2Df@8>
O^4Ko}
/** )5l9!1j
* @return Returns the page. QO3QR/Ww
*/ +\~Mx>Cn
public Page getPage(){ +$D~?sk
return page; f/]g@/`
} +"D*0gYD
sRSy++FRF
/** E{E%nXR)
* @return Returns the users. S@vLh=65
*/ BCw0kq@
publicList getUsers(){ <'<{|$Pw
return users; 'fIirGOl
} WHvxBd
e]u3[ao
/** QVQ?a&HYS
* @param page q/^&si
* The page to set. ns9a+QQ
*/ j:J{m0
publicvoid setPage(Page page){ bId@V[9
this.page = page; ,XmyC7y<
} S`&YY89{&
4&^BcWqA*f
/** l;'c6o0e
* @param users *m`KY)b=l
* The users to set. Auf2JH~
*/ jl~?I*Gr
publicvoid setUsers(List users){ &ajpD sz;
this.users = users; zIgD R
} J(%kcueb
VU
8~hF
/** %)G]rta#
* @param userService i*Ee(m]I
* The userService to set. 9UeK}Rl^n
*/ |\S p IFH1
publicvoid setUserService(UserService userService){ f
iu?mb=*
this.userService = userService; jwZBWt )5
} w65D;9/;
} 3*$)9'
i;8tA!
)gP0+W!u
^PI8Bvs>j
Hm55R
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, h` ,! p
x1{gw 5:
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 >s+*D=k
$r87]y!
么只需要: E0a &1j
java代码: (lR9x6yf
<X1^w
"=9kX`(1 y
<?xml version="1.0"?> tN:PWj5
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork q(I`g;MF
%{ToWLb{I
1.0//EN" "http://www.opensymphony.com/xwork/xwork- C"!k`i=Lj
ds" q1
1.0.dtd"> sZ9VXnz24
)I`Ma6bX
<xwork> 01" b9`jU
Zjx:1c= b
<package name="user" extends="webwork- "iY=1F"\R
qg#|1J6e
interceptors"> ~kW[d1'c
+>wBGVvS
<!-- The default interceptor stack name e4/Y/:vFO
5T4!'4n
--> ET 2@dY~
<default-interceptor-ref _r&,n\
T
'lD"{^
name="myDefaultWebStack"/> L\Y4$e9bF8
;}k9YlQrN
<action name="listUser" 8e3I@mv
- r!sY+Z>
class="com.adt.action.user.ListUser"> 8Cw+<A*
<param U%nLo[k
u+Q<>>lU
name="page.everyPage">10</param> Wy`ve~y
<result :AM5EO
BHa'`lCb
name="success">/user/user_list.jsp</result> -%eBip,'yl
</action> z<c%Xl\$%
.V Cfh+*J#
</package> ^yo~C3r~
>MeM
</xwork> n6Qsug$z
mjtmN0^SR
e7^B3FOx
X|w[:[P
qu:nV"~_
^E^Cj;od@
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 - .EH?{i
<yHa[c`L
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 3/i_?G
nF!6
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 bYKe5y=
7A mnxFC
F$k^px
?'$Yj>R6
@ysc?4% q
我写的一个用于分页的类,用了泛型了,hoho LnZC)cL
P/
}[>X}"_e
java代码: U$,W/G}m
Lm{qFu
$)O=3dNbo
package com.intokr.util; q&RezHK l
C6T?D5
import java.util.List; T7bDt
:7P/ZC%
/** hmQ;!9
* 用于分页的类<br> L
H8iHB
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ;0c
-+,
* [,)G\
* @version 0.01 V|n}v?f_q
* @author cheng ?8GggJC
*/ p&nPzZQL(
public class Paginator<E> { ;"K;D@xzh]
privateint count = 0; // 总记录数 %7y8a`}
privateint p = 1; // 页编号 zG. \xmp
privateint num = 20; // 每页的记录数 vk&6L%_~a
privateList<E> results = null; // 结果 ^I CSs]}1
+'VSD`BR
/** Ey#7L
M)
* 结果总数 !\6<kQg#
*/ f"}g5eg+
publicint getCount(){ ac%6eW0#
return count; 7B)m/%>3s
} 1z5Oi u
;#Y'SK
publicvoid setCount(int count){ ?;0w 1
this.count = count; %Y:"5fH
} 0Kytg\p}
lIUaGz|
/** 2]}4)_&d<e
* 本结果所在的页码,从1开始 s1GR!*z>
* N a$eeM
* @return Returns the pageNo. !JGe
.U5
*/ b?kY`LC
publicint getP(){ 00-cT9C3
return p; psFY=^69o
} }83a^E9L
"-T[D9(A
/** G=ly .
* if(p<=0) p=1 =G,wR'M
* !K[UJQs\
* @param p qbsmB8rh
*/ y<5RV>"Vg
publicvoid setP(int p){ $~+(si2
if(p <= 0) a-bj! Rs
p = 1; Pb`Uxv
this.p = p; 2t,N9@u=UN
} m0Geq.
}nUq=@ej
/** SYE+A`a
* 每页记录数量 2t[P-on
*/ A+w'quXn
publicint getNum(){ }Be;YIhG
return num; h0O t>e"
} ZO#f)>s2
E#!tXO&,
/** kfV}ta'^S
* if(num<1) num=1 .<Rw16O
*/ B{ A b#
publicvoid setNum(int num){ QJ,[K_
if(num < 1) 5(=5GkE)>
num = 1; 9,wD
this.num = num; 4^Y{ BS fF
} 7M/v[dwL
m!K`?P]:N
/** ('k9X cTPP
* 获得总页数 q
S qS@+p
*/ xWnOOE$i
publicint getPageNum(){ xt&4]M
V
return(count - 1) / num + 1; H[_i=X3-~
} mPL0s
>I@VHl O
/** ?Xl;>}zj
* 获得本页的开始编号,为 (p-1)*num+1 U EjP`
*/ ;aN_!!
r
publicint getStart(){ 5MCnGg@
return(p - 1) * num + 1; ve]hE}o/}
} dfP4SJqq
@9tzk [
/** <I#nwoHN
* @return Returns the results. w7@TM%nS
*/ 85T"(HhT
publicList<E> getResults(){ yT~rql
return results; OUk"aAo
} -3K01p
\(A A|;
public void setResults(List<E> results){ M>_vsI^I'
this.results = results; k-Yli21-/|
} 'eo/"~/*w
;,}Dh/&E
public String toString(){ Z%Fc
-KVt
StringBuilder buff = new StringBuilder 5%%e$o+
4`B3Kt`o
(); ;_=N
YG.
buff.append("{"); vSu
dT
buff.append("count:").append(count); KdBpfPny@
buff.append(",p:").append(p); apOa E7|
buff.append(",nump:").append(num); Kl,NL]]4*5
buff.append(",results:").append U`aB&[=$
k2@]nW"S
(results); 'u:-~nSX)
buff.append("}"); |A/H*J,
return buff.toString(); ,v<7O_A/e
} ]rG/?1'^i
/9e?uC6
} n$F~
,$} xPC
uGv|!UQw