Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 [V_+/[AA)
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 F!fsW9
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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 c^<~Y$i
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 8F&Y;
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分页支持类: S!n?b|_
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java代码: gquvVj1oT
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package com.javaeye.common.util; .K]Uk/W
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import java.util.List; !L@<?0xLW
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publicclass PaginationSupport { *
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publicfinalstaticint PAGESIZE = 30; {
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privateint pageSize = PAGESIZE; e,r7UtjoxR
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privateList items; M~n./wyC
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privateint totalCount; -$X4RS
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privateint[] indexes = newint[0]; /::Y &&$f
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privateint startIndex = 0; .
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public PaginationSupport(List items, int ef)zf+o
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totalCount){ ,p#r; O<O
setPageSize(PAGESIZE); ~L>86/hP,N
setTotalCount(totalCount); |fIyq}{7
setItems(items); T:Ovh.$
setStartIndex(0); @SyL1yFX
} ?;H}5>^8P
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public PaginationSupport(List items, int :5.F
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totalCount, int startIndex){
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setPageSize(PAGESIZE); 2wDDVUwy B
setTotalCount(totalCount); |2%|=
setItems(items); U$<"
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setStartIndex(startIndex); /%s:aO
} ! nvg:$.&
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public PaginationSupport(List items, int *nHuGla
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totalCount, int pageSize, int startIndex){ vf$IF|
setPageSize(pageSize); M0~%[nX
setTotalCount(totalCount); y4LUC;[n
setItems(items); Goc?HR
setStartIndex(startIndex); T1*.3_wtP
} 7Xu# |k
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publicList getItems(){ fISK3t/=C
return items; >Q!}tbg~9
} /PeT4hW}
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publicvoid setItems(List items){ *U]&a^N
this.items = items; $+_1F`
} y(MB_B7j
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publicint getPageSize(){ G_J}^B*?%v
return pageSize; 16Jq*hKU
} iB"ji4[z
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publicvoid setPageSize(int pageSize){ T'vI@i9
this.pageSize = pageSize; Ul9^"o
} u~j
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publicint getTotalCount(){ lFnYQab
return totalCount; "n`z`{<n
} aEvbGo
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publicvoid setTotalCount(int totalCount){ P1T{5u!T
if(totalCount > 0){ -` ViuDX=
this.totalCount = totalCount; D|*w6p("z
int count = totalCount / N+B!AK0.
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pageSize; c8"Qmy
if(totalCount % pageSize > 0) mV`R'*1UC
count++; k|?[EWIi^
indexes = newint[count]; ?L7DVwVa,I
for(int i = 0; i < count; i++){ p|2GPrA]aL
indexes = pageSize * 1h?ve,$
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i; EI6kBRMo
} ~M{/cv
}else{ jIT|Kk&]
this.totalCount = 0; )Bn
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} *>:phs~r{
} _Ffg"xoC
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publicint[] getIndexes(){ D^6iQW+.P
return indexes; I V#8W
} O}Pqbx&
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publicvoid setIndexes(int[] indexes){ UTKyPCfj
this.indexes = indexes; ;Y;r%DJ
} V&:x+swt
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publicint getStartIndex(){ F +(S-Qk1
return startIndex; fEXFnQ#
} {c9 fv H
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publicvoid setStartIndex(int startIndex){ 7`J2/(
if(totalCount <= 0) E-.X%xfO
this.startIndex = 0; \^"Vqx
elseif(startIndex >= totalCount) 8Lx/ZGy
this.startIndex = indexes 2A~o)7JaZ
[(x*!,=
[indexes.length - 1]; 4jebx
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elseif(startIndex < 0) 4z(B`t~7
this.startIndex = 0; y*+8Z&i.:
else{ ~9FL]qo
this.startIndex = indexes uc@4fn
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[startIndex / pageSize]; 27ZqdHd
} -`XS2
} dB6,pY(
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publicint getNextIndex(){ }WIkNG4{Z
int nextIndex = getStartIndex() + {Z8GG
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pageSize; lb'tVO
if(nextIndex >= totalCount) ,Kj>F2{
return getStartIndex(); S!u8JG1
else aq_K,li#w
return nextIndex; {f-O~P<Z4
} _J6
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publicint getPreviousIndex(){ wW*7
int previousIndex = getStartIndex() - 4RVqfD
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pageSize; "JSIn"/
if(previousIndex < 0) Cwls e-
return0; 6?[P^{GpH
else ;&6
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return previousIndex; p=nbsS~":
} ^PNDxtd|v
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} |D-[M_T5
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抽象业务类 zJy=1r
java代码: a r8iuwfZ
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/** Z
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* Created on 2005-7-12 =U*D.p*%f
*/ xkRMg2X.>9
package com.javaeye.common.business; 0ex.~S_Oj4
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import java.io.Serializable; YOLzCnI4
import java.util.List; .kU^)H"l
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import org.hibernate.Criteria; f:+/=MW
import org.hibernate.HibernateException; iS+"Jsz
import org.hibernate.Session; I{dy,\p
import org.hibernate.criterion.DetachedCriteria; b)'CP Cu*
import org.hibernate.criterion.Projections; RKzty=j4
import ,on]Fts
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org.springframework.orm.hibernate3.HibernateCallback; kE<CuO
import /5Qh*.(S
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org.springframework.orm.hibernate3.support.HibernateDaoS (4 ZeyG@
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upport; }_KzF~
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import com.javaeye.common.util.PaginationSupport; 5]I)qij
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public abstract class AbstractManager extends M^oL.'
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HibernateDaoSupport { bdstxjJ`
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privateboolean cacheQueries = false; 'qT;Eht5
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privateString queryCacheRegion; *$%~/Q@]
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publicvoid setCacheQueries(boolean id9QfJ9t
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cacheQueries){ 0>CG2 SRn
this.cacheQueries = cacheQueries; K_L7a>Fr
} kl:/PM^
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publicvoid setQueryCacheRegion(String -(TC'
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queryCacheRegion){ #1$4<o#M
this.queryCacheRegion = QEqYqAGzu|
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queryCacheRegion; Sc{&h8KMTb
} rT4Q^t"
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publicvoid save(finalObject entity){ gBV4IQ
getHibernateTemplate().save(entity); H.l0kBeG
} d)uuA;n
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publicvoid persist(finalObject entity){ ib(|}7Je
getHibernateTemplate().save(entity); 9U<WR*H
} Td|,3
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publicvoid update(finalObject entity){ BTr
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getHibernateTemplate().update(entity); JzN "o'
} #0r^<Yn
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publicvoid delete(finalObject entity){ !U@ETo
getHibernateTemplate().delete(entity); $,Xn@4
} _$T
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publicObject load(finalClass entity, ,?m@Ko7Y
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finalSerializable id){ -n"f>c_{>
return getHibernateTemplate().load .&b^6$dC
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(entity, id); 66>X$nx(z
} 2* `kkS
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publicObject get(finalClass entity, M)K!!Jqh
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finalSerializable id){ W!ug^2"
return getHibernateTemplate().get `_LQs9J0J
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(entity, id); $G0e1)D
} th*!EFA^o
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publicList findAll(finalClass entity){ R $<{"b
return getHibernateTemplate().find("from Jityb}Z"
(&*Bl\YoX
" + entity.getName()); h-(NWxK+
} P2ySjgd
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publicList findByNamedQuery(finalString >N!
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namedQuery){ =4x6v<
return getHibernateTemplate D`41\#ti
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().findByNamedQuery(namedQuery); 2vUcSKG7
} R+0fs$su
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publicList findByNamedQuery(finalString query, '$yy
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finalObject parameter){ D{8B;+
return getHibernateTemplate hQ:wW}HWW
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().findByNamedQuery(query, parameter); B;Z _'.i,d
} ;gHcDnH)
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publicList findByNamedQuery(finalString query, (F;*@Z*R
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finalObject[] parameters){ ,?K5/3ss
return getHibernateTemplate 7dB_q}<
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().findByNamedQuery(query, parameters); #WDpiV7B
} Y -BZV |
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publicList find(finalString query){ 9nO&d(r g
return getHibernateTemplate().find U;ujN 8
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(query); #EKnjh=Uq
} "j&p3
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publicList find(finalString query, finalObject D ][I#vh
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parameter){ +N~{6*@uz,
return getHibernateTemplate().find HF&dHD2f
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(query, parameter); 3uvl'1(%J
} Iw$T'I+4W
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public PaginationSupport findPageByCriteria ~d3BVKP5
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(final DetachedCriteria detachedCriteria){ guy!/zQ>A
return findPageByCriteria Br$/hn=
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5|
(detachedCriteria, PaginationSupport.PAGESIZE, 0); &$qIJvMiK
} "1P2`Ep;
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public PaginationSupport findPageByCriteria z;0]T=g
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(final DetachedCriteria detachedCriteria, finalint SN QLEe
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startIndex){ Eh`W J~
return findPageByCriteria K^I$05idi
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(detachedCriteria, PaginationSupport.PAGESIZE, =Y3 d~~
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startIndex); 9I|Q`j?p`
} 3
}rx(
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public PaginationSupport findPageByCriteria PO2]x:
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(final DetachedCriteria detachedCriteria, finalint /#xYy^`
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pageSize, 4vH.B)S-
finalint startIndex){ %N<>3c<8P
return(PaginationSupport) 61TL]S8
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getHibernateTemplate().execute(new HibernateCallback(){ Rn whkb&&
publicObject doInHibernate nm,Tng
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(Session session)throws HibernateException { 69C
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Criteria criteria = JDMsco+j5
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detachedCriteria.getExecutableCriteria(session); lU3Xd_v
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int totalCount = l}Vg;"1'J
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((Integer) criteria.setProjection(Projections.rowCount X`daaG_l
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()).uniqueResult()).intValue(); A'? W5~F
criteria.setProjection tbi(e49S
t== a(e
(null); -IS?8\Q<
List items = z: W1(/W~
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criteria.setFirstResult(startIndex).setMaxResults [6Nzz]yy
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(pageSize).list(); |.U-
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PaginationSupport ps = 51M'x_8
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new PaginationSupport(items, totalCount, pageSize, #*K!@X
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startIndex); p$%g$K
return ps; _:;j)J0
} ;%aWA
}, true); u&Dd9kMz
} k+&1?]
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public List findAllByCriteria(final Z$a4@W9o
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DetachedCriteria detachedCriteria){ ZZl4|
return(List) getHibernateTemplate 32V,25 (`5
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().execute(new HibernateCallback(){ F1o"H/:n
publicObject doInHibernate c)o[3o7
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(Session session)throws HibernateException { RJI*ZNbA
Criteria criteria = -x1O|q69
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detachedCriteria.getExecutableCriteria(session); ui6B
return criteria.list(); x5Ee'G(
} /L"&'~
}, true); {VE$i2nC8
} !bCLi>8
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public int getCountByCriteria(final W(tXq
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DetachedCriteria detachedCriteria){ $yb8..+
Integer count = (Integer) s2ys>2k
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getHibernateTemplate().execute(new HibernateCallback(){ VI`x
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publicObject doInHibernate [%8+Fa~Wa
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(Session session)throws HibernateException { [0e]zyB+
Criteria criteria = BPd]L=,/
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detachedCriteria.getExecutableCriteria(session); <cz~q=%v2&
return t hDE
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criteria.setProjection(Projections.rowCount t(MlZ>H
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()).uniqueResult(); K~WwV8c9;
} 2h6F j&
}, true); o&~z8/?LA
return count.intValue(); -}juj;IVv
} Ve8`5
} BWX&5""
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用户在web层构造查询条件detachedCriteria,和可选的 uYMW5k_,>
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 <$njU=YE&
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PaginationSupport的实例ps。 W3 8=fyD
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ps.getItems()得到已分页好的结果集 e:V,>RbC0s
ps.getIndexes()得到分页索引的数组 -RH ?FJ
ps.getTotalCount()得到总结果数 1=(i{D~
ps.getStartIndex()当前分页索引 WuGm~<NS
ps.getNextIndex()下一页索引
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ps.getPreviousIndex()上一页索引 iQGoy@<R
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 &GD7ldck
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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 !s)$_tG
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一下代码重构了。 \AK|~:\]
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我把原本我的做法也提供出来供大家讨论吧: bo -Gh`
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首先,为了实现分页查询,我封装了一个Page类: #/jHnRrQ
java代码: Dk"M8_-_
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/*Created on 2005-4-14*/ g<dCUIbcQ
package org.flyware.util.page; h.Dk>H_G
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/** z
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* @author Joa YI|Gpq
* yED^/=\)}
*/ oF6MV&q/
publicclass Page { slmxit
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/** imply if the page has previous page */ %8{_;-f
privateboolean hasPrePage; +8Px` v1L
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/** imply if the page has next page */ qlxW@|
privateboolean hasNextPage; 'q^Gg;c>+
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/** the number of every page */ J-ZM1HoB
privateint everyPage; RQ'c~D)X
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/** the total page number */ s*X\%!l9
privateint totalPage; #~f+F0#%?
jlP7'xt1%
/** the number of current page */ '_<`dzz
privateint currentPage; PmY:sJ{M
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/** the begin index of the records by the current 8{l=`y"nB
&; skB.
query */ }:8>>lQ
privateint beginIndex; 4a |Fx
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/** The default constructor */ UmE{>5Pt
public Page(){ q{ 1U
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} *Kkw,qp/
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/** construct the page by everyPage A(p
* @param everyPage I}v#r8'!
* */ QX=;,tr
public Page(int everyPage){ ]."c4S_)|
this.everyPage = everyPage; 1Qu,]i`
} j*`!o/=LI
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/** The whole constructor */ <3x#(ms!!
public Page(boolean hasPrePage, boolean hasNextPage, LD~'^+W
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int everyPage, int totalPage, ^ks^9*'|j
int currentPage, int beginIndex){ tQaCNS$=
this.hasPrePage = hasPrePage; e:D"_B
this.hasNextPage = hasNextPage; * _lo;
this.everyPage = everyPage; Lp)8SmN
this.totalPage = totalPage; 26VdRy{[
this.currentPage = currentPage; Ur(o&,
this.beginIndex = beginIndex; mRY6[*u
} L)'rM-nkFh
] *VF Ws
/** aQ:f"0fL
* @return &:#8ol(n5b
* Returns the beginIndex. "4hpU]4j
*/ Z;'.pU~
publicint getBeginIndex(){ 5l/l]
return beginIndex; xBfe8lor
} $2C GRhC
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/** i!oj&&
* @param beginIndex {/xs9.8:JX
* The beginIndex to set. b Ne\{k
*/ -b0'Q
publicvoid setBeginIndex(int beginIndex){ `$SEkYdt
this.beginIndex = beginIndex; nSQ}yqM)
} +Cg"2~
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/** ' VEr4&
* @return L(n/uQ
:
* Returns the currentPage. %=4ak]As
*/ 9Y%?)t.2
publicint getCurrentPage(){ LsQ8sFP_"
return currentPage; c_bVF 'Bz
} )USC
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/** TWR$D
* @param currentPage $dp#nyP
* The currentPage to set. ;;'a--'"
*/ fTHun?Vn
publicvoid setCurrentPage(int currentPage){ [&qbc#L
this.currentPage = currentPage; 'cF%4F
} nlebFDb7
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/** 51M^yG&M
* @return l \^nC2
* Returns the everyPage. !ObE{2Enf
*/ 2vkB<[tSs
publicint getEveryPage(){ 5nx<,-N*BP
return everyPage; CSL{Q
} 7IT l3>
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/** MFH"$t+
* @param everyPage .?0>5-SfY
* The everyPage to set. N~$Zeq=
*/ Lubs{-5lk
publicvoid setEveryPage(int everyPage){ rFq@]t3q
this.everyPage = everyPage; fcE)V#c"g
} t+ S~u^
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/** ;sChxQ=.^
* @return |#&V:GZp
* Returns the hasNextPage. mUt,Z^ l`
*/ A} -&C
publicboolean getHasNextPage(){ %[nR|a<
return hasNextPage; {b,2;w}95
} r9]
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/** f#v#)Gp+
* @param hasNextPage XD^dlL
* The hasNextPage to set. ^RV
*/ ("?&p3];b
publicvoid setHasNextPage(boolean hasNextPage){ 8Z
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this.hasNextPage = hasNextPage; W`N}
} B [+(r
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/** v_z..-7Dq+
* @return 9k\)tWe
* Returns the hasPrePage. ?Q96,T-)
c
*/ \L ]
publicboolean getHasPrePage(){ _r\$NgJIM
return hasPrePage; -^iUVO`z
} _~;&)cn,0
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/** N-2([v
* @param hasPrePage 6 u-$
* The hasPrePage to set. :xFu_%7
*/ dn ZzA
publicvoid setHasPrePage(boolean hasPrePage){ #ya\Jdx
this.hasPrePage = hasPrePage; WR/o
@$/
} (#6AKr9K
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/** SyK 9Is{8
* @return Returns the totalPage. OM.k?1%+M
* XXW]0{k:y
*/ -AjH}A[!
publicint getTotalPage(){ bLgL0}=n
return totalPage; *u>lx!g
} Kt
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7\A4vUI3
/** l{Jt s I
* @param totalPage :O $@shV
* The totalPage to set. '>j<yaD'
*/ X^}A*4j
publicvoid setTotalPage(int totalPage){ \q~w<%9Dq
this.totalPage = totalPage; nPcS3!7B#
} 6HoqEku/Q
Q}kfM^i
} Ji;SY{~kv
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} h[>U
ZJ;LD*
上面的这个Page类对象只是一个完整的Page描述,接下来我写了一 Dv&>*0B
25:Z;J>
个PageUtil,负责对Page对象进行构造: xXX/]x>
java代码: 1Cm~X$S.
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/*Created on 2005-4-14*/ Z@3l%p6V
package org.flyware.util.page; WwuZ(>|
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import org.apache.commons.logging.Log; WsR+Np@c
import org.apache.commons.logging.LogFactory; `)32&\
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/** n~tqO!q
* @author Joa V/PAi.GZ
* AoYaVlKG8
*/ XS?gn.o\
publicclass PageUtil { .WvlaPK
c<wavvfUo
privatestaticfinal Log logger = LogFactory.getLog Yd:Q`#7A
xCWz\-;
(PageUtil.class); J~KX|QY.S
d?A}qA[(
/** #;[Bl=3(
* Use the origin page to create a new page q"akrI38
* @param page j!\dn!Xwt
* @param totalRecords ,_jC$
* @return IG< H"tQ
*/ Qzqc .T
publicstatic Page createPage(Page page, int u-JpI-8h
1<.5ub*i4
totalRecords){ jk*tL8?i
return createPage(page.getEveryPage(), a?F!,=F
gZO&r#
page.getCurrentPage(), totalRecords); b9~A-Z
} *6Q|}b[qcD
<8!
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/** 1l5JP|x
* the basic page utils not including exception fRB5U'
ZF6c{~D
handler #(KDjnP[
* @param everyPage P(,?#+]-
* @param currentPage `!vUsM .d
* @param totalRecords O^Q,-=tA\
* @return page Zd!U')5/
*/ z.36;yT/
publicstatic Page createPage(int everyPage, int o.m:3!RW
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currentPage, int totalRecords){ j+rG7z){K
everyPage = getEveryPage(everyPage); h !gk s-0
currentPage = getCurrentPage(currentPage); OGOND,/R?/
int beginIndex = getBeginIndex(everyPage, s?2$ue&-f
(UL4+ta
currentPage); ;"kaF!
int totalPage = getTotalPage(everyPage, q_V0+qH
u JY)4T
totalRecords); v+G=E2Lhv
boolean hasNextPage = hasNextPage(currentPage, QA3/
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totalPage); ^7^N}x@
boolean hasPrePage = hasPrePage(currentPage); W3H+.E
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returnnew Page(hasPrePage, hasNextPage, 1yQejw
everyPage, totalPage, G2Vv i[c
currentPage, eJ0?=u!x
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beginIndex); i,IB!x
} ?t](a:IX
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privatestaticint getEveryPage(int everyPage){ +Q$h ]^>~
return everyPage == 0 ? 10 : everyPage; k{;,6H
} F@ Swe
#bH_Dg5I
privatestaticint getCurrentPage(int currentPage){ \xv;sl$f
return currentPage == 0 ? 1 : currentPage; <-'$~G j
} I,yC
D7l_
@$9'@")
privatestaticint getBeginIndex(int everyPage, int f>`dF?^6
]:>,A@7
currentPage){ d?wc*N3
return(currentPage - 1) * everyPage; f| _u7"OX
} /!h;c$
zk-.u}RBFG
privatestaticint getTotalPage(int everyPage, int fGhn+8VfX
eET&pP3Rp
totalRecords){ 1W7%1FA
int totalPage = 0; oND@:>QBF
?;[w" `"
if(totalRecords % everyPage == 0) &xRo^iV?
totalPage = totalRecords / everyPage; wE+${B03
else 8>hwK )av
totalPage = totalRecords / everyPage + 1 ; <-D/O$q
Mmpfto%i
return totalPage; x
}Ad_#q
} $9Hcdbdm
]vwW]O7
privatestaticboolean hasPrePage(int currentPage){ X 1
57$
return currentPage == 1 ? false : true; }=c85f~i
} PDs@?nz,
lXcx@#~
privatestaticboolean hasNextPage(int currentPage, }zhGS!fO
9$2/MT't
int totalPage){ 'yMF~r3J
return currentPage == totalPage || totalPage == dFKM
8_jH
%CK^Si%+
0 ? false : true; ep)>X@t
} y;s`P.
g$b<1:8
j~!X;PV3
} xlQBe-Wg
,7<f9 EVY
[VE8V-
C=eF.FB;'
O)[1x4U
上面的这两个对象与具体的业务逻辑无关,可以独立和抽象。 q
FAT]{{
iyg*Xbmi~.
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 w@{= nD4p
rx] @A
做法如下: {WYX~Mvvj
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 zG(\+4GE!
"1%5,
的信息,和一个结果集List: DAXX;4
java代码: 0tXS3+@n=
))"6ern
9Gnc9_]I;W
/*Created on 2005-6-13*/ XT4{Pe7{[P
package com.adt.bo; T\D}kQM
CLUW!F
import java.util.List; ~vyf4TF<#
FY#C.mL
import org.flyware.util.page.Page; ?.Ca|H<
c9&xe"v
/** "$YJX1u3
* @author Joa T( U_
*/ 2Eu`u!jhx
publicclass Result { Jcrw#l8|C
'F9 jq
private Page page; ;EP:o%r
H"
3fT 0
private List content; T7hcnF$
v@
lM3_rbO
/** ZzJ?L4J5v
* The default constructor Na]:_K5Dp
*/ !
t?iXZ
public Result(){ Yfzl%wc
super(); t*1fLumXR
} 1cpiHZa
#."-#"0
/** $Avjnm
* The constructor using fields BHU6t<G
* e#$]Y?,
* @param page l3ko?k
* @param content a%/9v"}
*/ 4NheWM6
public Result(Page page, List content){ &m)6J'q3k
this.page = page; |EX(8y
this.content = content; 1W^taJH]
} o$jLzE"
dMv=gdY
/** iTgt}]L
* @return Returns the content. N"Zt47(
*/ R{<kW9!
publicList getContent(){ $P^q!H4D
return content; PNgY>=Y
} }ppN k:B
a|t$l=|DD
/** sBvzAVBL
* @return Returns the page. Vc&!OE
*/ `ZYoA
t]C~
public Page getPage(){ 5q3JI
return page; ls\WXCH
} 4i)1'{e
Yvw(tj5_5
/** c|e~BQdRw
* @param content N} G[7Rp8l
* The content to set. bzBEX mC
*/ /?5 1D@
public void setContent(List content){ gc_:%ki
this.content = content; <\rT%f}3^
} ,<(}|go
#+Ir>GU
/** QwW&\h[8?
* @param page %?0:vn
* The page to set. nLbFg0?+t
*/ +"\sc;6m.
publicvoid setPage(Page page){ HVR /7&g
this.page = page; q;T{|5/O
} _hAcJ{Y
} lA|
5E?
:%tU'w
W <9T0sZ
9UdM`v)(
n\Z!ff/
2. 编写业务逻辑接口,并实现它(UserManager, ! `
h5*JkRm
UserManagerImpl) lk/n}bx
java代码: SD"FErJ
6a(yp3
M'?,] an
/*Created on 2005-7-15*/ 7OcWC-<
package com.adt.service; EU2$f
[L3=x;U
import net.sf.hibernate.HibernateException; o5Dk:Bw
=MQoC:l
import org.flyware.util.page.Page; cvn@/qBq*t
bkOv2tZ
import com.adt.bo.Result; ~^NtO
g!g#]9j
/** f',Op1o
* @author Joa ity & v9
*/ e>} s;H,
publicinterface UserManager { b1(T4w6
5Yg'BkEr
public Result listUser(Page page)throws .?8;q A
RD!&LFz/}
HibernateException; 5bRJS70M
\r/rBa\
} LA!?H]
&PR5q7
Lu?C-$a C
x>**;#7)
}~YA5^VQ$
java代码: j@n)kPo,1
66g9l9wm(
!EvAB+`jLI
/*Created on 2005-7-15*/ z6KCv(zvB
package com.adt.service.impl; QmQ=q7
Eq% }
import java.util.List; /Wi[OT14
3atBX5
import net.sf.hibernate.HibernateException; Kr?TxhUHd
G!Op~p@Jm
import org.flyware.util.page.Page; :vmH]{R
import org.flyware.util.page.PageUtil; JB%',J
vk}n,ecl
import com.adt.bo.Result; QVv#fy1"6
import com.adt.dao.UserDAO; j_qbAP
import com.adt.exception.ObjectNotFoundException; +Zb;Vn4
import com.adt.service.UserManager; @3>u@
iW)8j 8
/** Lm iOhx
* @author Joa .N,bIQnj
*/ b_$4V3TA
publicclass UserManagerImpl implements UserManager { `xKp%9
Z_LFIz*c
private UserDAO userDAO;
ncZ+gzK|"
`{f}3bO7C
/** lS"T4 5
* @param userDAO The userDAO to set. jte.Xy~g
*/ 6gL#C&
publicvoid setUserDAO(UserDAO userDAO){ -"R2
this.userDAO = userDAO; iJ ($YvF4
} 9)h"-H;5:
WltQ63u
/* (non-Javadoc) uF X#`^r`
* @see com.adt.service.UserManager#listUser j%Y#(Q>
-Fi`Z$
(org.flyware.util.page.Page) 8Q.T g.
*/ 5-FQMXgThc
public Result listUser(Page page)throws rF3wx.
IY_iB*T3jt
HibernateException, ObjectNotFoundException { AgWa{.`f:
int totalRecords = userDAO.getUserCount(); g1;:KzVv
if(totalRecords == 0) ntu5{L'8
throw new ObjectNotFoundException ](Xb_xMf
|5X^u+_
("userNotExist"); M f}~{+
page = PageUtil.createPage(page, totalRecords); 5^}\4.eXo
List users = userDAO.getUserByPage(page); b10cuy|a/X
returnnew Result(page, users); o5u3Fjz3
} <kfnpB=
[xbSYu,&
} nyX2|m&
cF\;_0u
-$t{>gO#Y
jkQ*D(;p
g!|=%(G=
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 nxO"ua
aKJwofD
询,接下来编写UserDAO的代码: {IjF+@I
3. UserDAO 和 UserDAOImpl: %{7|1>8
java代码: !-g{[19\
$1SPy|y
UgRhWV~f0
/*Created on 2005-7-15*/ -fM1nH&
package com.adt.dao; *o]L|Vu
ru'F6?d
import java.util.List; FW;m\vu
)n1_(;
import org.flyware.util.page.Page; zp6C3RG(
Cw~q4A6'
import net.sf.hibernate.HibernateException; hl;u'_AB
4aug{}h("
/** l\f*d6o
* @author Joa O8f?; ]
*/ #^#PPO
publicinterface UserDAO extends BaseDAO { Zj_b>O-V
"N;`1ce
publicList getUserByName(String name)throws XUrXnz|>
Lk|hQ
HibernateException; M|VyV(f
=WyDp97@+
publicint getUserCount()throws HibernateException; []D&bYpv
UJ%R
publicList getUserByPage(Page page)throws x-XD.qh7Hr
FOb0uj=(v
HibernateException; f0!))/rSD
4d"r^y'
} f}6s
Q5
5sdn[Tt##
{M3qLf~z#C
qjc8fP2
yZAS# ko}}
java代码: ht|z<XJ
mD/9J5:
Ltv]pH}YN
/*Created on 2005-7-15*/ vx\r!]
package com.adt.dao.impl; % BVs47g
Y2|#V#
import java.util.List; "33Fv9C#bK
{]*c29b>
import org.flyware.util.page.Page; >f^r^P
dMPc:tJT
import net.sf.hibernate.HibernateException; ,k.3|aZE
import net.sf.hibernate.Query; 'SO %)B
>~#yu&*D
import com.adt.dao.UserDAO; -#7'r<I9@
d^@ dzNv
/** _uWpJhCT
* @author Joa ?fiIwF)
*/ 7X`l&7IXP
public class UserDAOImpl extends BaseDAOHibernateImpl Jlri*q"hE
&]g}u5J!=
implements UserDAO { :uP,f<=)K
UG'Q]S#!
/* (non-Javadoc) YA''2Ii
* @see com.adt.dao.UserDAO#getUserByName t\?ik6
# Nk;4:[
(java.lang.String) :=}BN
*/ R}'bP
publicList getUserByName(String name)throws G"klu
6rh5h:
HibernateException { yu;+o3WlK
String querySentence = "FROM user in class <W|3\p6
@>u]4Jn
com.adt.po.User WHERE user.name=:name"; YO#M/%^j
Query query = getSession().createQuery WgR).Yx
wZG\>9~
(querySentence); H]P.
x!I
query.setParameter("name", name); xRJ\E }/7
return query.list(); 7OC#8,
} pN!}UqfI-
#~#R-
/* (non-Javadoc) Diy8gt
* @see com.adt.dao.UserDAO#getUserCount() V\t.3vT
*/ 6{x(.=
publicint getUserCount()throws HibernateException { Vdtry@Q
int count = 0; j:<n+:HC
String querySentence = "SELECT count(*) FROM ,">]`|?
s2teym,uG
user in class com.adt.po.User"; RwKdxK+;
Query query = getSession().createQuery $Oq^jUJ
V:qSy#e
(querySentence); 6tX q:
count = ((Integer)query.iterate().next 11TL~xFh
W6f/T3
()).intValue(); 0vFD3}~>
return count; OSlvwH%(EE
} <nE>XAI_7
| 1E|hh@k
/* (non-Javadoc) 9}l33T4T
* @see com.adt.dao.UserDAO#getUserByPage prYs
$j
3wOZ4<B
(org.flyware.util.page.Page) ?$vCW|f
*/ qo p^;~
publicList getUserByPage(Page page)throws sA/pVU
XR+Y=R
HibernateException { TX$r`~
String querySentence = "FROM user in class cimp/n"
}B8IBveu
com.adt.po.User"; 6;u$&&c(
Query query = getSession().createQuery u2[iM d
aAJU`=uq
(querySentence); O/,aJCe
query.setFirstResult(page.getBeginIndex()) hHN'w73z
.setMaxResults(page.getEveryPage()); 18~>ZR
return query.list(); !6BW@GeF]
} 9XPo3;
Px$/ _`H
} 8C[C{qOJ
'd.EC#
b6}H$Sx~
|rJ=Ksc
y<HO:kZ8`
至此,一个完整的分页程序完成。前台的只需要调用 .P;*D ws
X*M#FT-
userManager.listUser(page)即可得到一个Page对象和结果集对象 q;QbUO
!u_Y7i3^
的综合体,而传入的参数page对象则可以由前台传入,如果用 ;gBRCZ
i;NUAmx
webwork,甚至可以直接在配置文件中指定。 Anscr
)^m%i]L_
下面给出一个webwork调用示例: ]e^c=O`$
java代码: xgpi-l
l;JA8o\x
}!;s.[y
/*Created on 2005-6-17*/ b?TO=~k,
package com.adt.action.user; X *&[u7No
)=5ng-
import java.util.List; g6Q !8
L{hnU7sY
import org.apache.commons.logging.Log; LA@w:Fg
import org.apache.commons.logging.LogFactory; .z
6fv
import org.flyware.util.page.Page; MZlk0o2
3|1ilP
import com.adt.bo.Result; R($KSui
import com.adt.service.UserService; \=uKHNP?#
import com.opensymphony.xwork.Action; q8s0AN'@t'
0o+6Q8q
/** 29!q!g |
* @author Joa Gs9:6
*/ v'VD0+3[H
publicclass ListUser implementsAction{ RnhL<
Ywu
!OBEM1~
1
privatestaticfinal Log logger = LogFactory.getLog C!Rs^/
`|,`QqDQ
(ListUser.class); UG2nX3?
NXNY"r7~
private UserService userService; #tZ4N7
T2SP
W@#Z3
private Page page; }&n<uUD H
i|T)p_y(!a
privateList users; UG)8D5
R,F[XI+=N
/* v=_6XF
* (non-Javadoc) /RHo1
* Svc|0Ad&
* @see com.opensymphony.xwork.Action#execute() oXxCXO,q
*/ :lB=Lr)
publicString execute()throwsException{ BO~PT,QrF
Result result = userService.listUser(page); ^j".
page = result.getPage(); 9T|IvQK8
users = result.getContent(); .a._NW
return SUCCESS; r :F
} 8"dv _`ym
?pn}s]*/
/** TiYnc3Bz}J
* @return Returns the page. $% 1vW=d
*/ %n
hm
public Page getPage(){ q o\?o
return page; Xlb0/T<g!
} <^zHE=h"
=Qgt${|
/**
Xtp"QY
p
* @return Returns the users. l2l(_$@3
*/
9A,^c;
publicList getUsers(){ _cc#Qlw 7
return users; tI7:5Cm
} ^my].Qpt
-u?S=h}
/** 6IWxPt~
* @param page aj?a^}X
* The page to set. LxpuhvIO
*/ u%/goxA
publicvoid setPage(Page page){ N_pJk2E
this.page = page; lWqrU1Sjl
} nzmDA6d
xia |+
/** BM(]QUxRd
* @param users $ZNu+tn
Y
* The users to set. 7}vg.hmZ
*/ $6CwkM:
publicvoid setUsers(List users){ {;.T7dL
this.users = users; Ma+$g1$
} h+a S4Q&
~_s{0g]B
/** G 2mX;
* @param userService Y_]De3:V0B
* The userService to set. lhtZaU~V
*/ #(1j#\
publicvoid setUserService(UserService userService){ \#rIQOPl?
this.userService = userService; 1&P<
} C#H:-Q&
} z8[yt282
v*9<c{a
(XXheC
h68]=KyK
Ton94:9bZ
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, r)i>06Hd
ixV0|P8,c
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 MNg^]tpf
sYdRh?Hq
么只需要: +Y
V|ij
java代码: RGK8'i/X
8o/}}=m$
\'M3|w`f
<?xml version="1.0"?> 5bA)j!#)|X
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork ;/0 Q1-
w=}uwvn NX
1.0//EN" "http://www.opensymphony.com/xwork/xwork- ]q6;#EUr?
B}eA\O4}I
1.0.dtd"> z.6$W^
vAX|hwn;
<xwork> l9Q(xuhv
(D
9Su^:1
<package name="user" extends="webwork- ,&d@O>$E:
0x9x@gF
interceptors"> FVKW9"AyW
o=RM-tR`v
<!-- The default interceptor stack name {VP$J"\e
c)Ic#<e(
--> 1pCieTz!PN
<default-interceptor-ref /1 RAAa
!I\!;b
name="myDefaultWebStack"/> .^bft P\
vm'5s]kdh
<action name="listUser" k/03ZxC-
E0/mSm"(T
class="com.adt.action.user.ListUser"> S2>c#BQ
<param QaGlR`Y
Q`#4W3-,
name="page.everyPage">10</param> n$aA)"A #
<result KIeT!kmDl
7?v#'Ies
name="success">/user/user_list.jsp</result> [DHoGy,P
</action> %hN.ktZ/s
F3oQ^;xB
</package> &3Zy|p4V<
>|Q:g,I
</xwork> efG6v
i-U4RZE
fZKt%m
4gSH(*}
pr,p=4m{\
iU+nqY'
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 dJ:MjQG`W
=op%8NJf
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。 (]*H[)F/
#&8}<8V
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 ,uz ]V1
8wH.et25k
{ m8+Wju}
\uG`|Dn
'<iK*[NW
我写的一个用于分页的类,用了泛型了,hoho QFPfIb/
:
t$l.+B
java代码: E^ hHH?w+
% p?brc
d {2
package com.intokr.util; QO{y/{
utlpY1#q/
import java.util.List; XA_FOw!cX
Hqz?E@bc@
/** _kFYBd
* 用于分页的类<br> ;oH,~|K
* 可以用于传递查询的结果也可以用于传送查询的参数<br> ~9Cz6yF
* ]J2:194
* @version 0.01
,%#
* @author cheng '[ P}&<ie,
*/ )<4_:
public class Paginator<E> { 1;eX&
privateint count = 0; // 总记录数 02JL*
privateint p = 1; // 页编号 r!N]$lB
privateint num = 20; // 每页的记录数 ]r]k-GZ$
privateList<E> results = null; // 结果 m:Go-tk
ts9pM~_~
/** PHM:W%g:
* 结果总数 YJ7V`Np
*/ ;eB ~H[S/
publicint getCount(){ \[wCp*;1}
return count; @=]8^?$t
0
} ?T:
jk4+
(d2@Mz
publicvoid setCount(int count){ J_#R 87
this.count = count; WNa0,
} &;q<M_<
Ln#a<Rx.E7
/** =)<3pG O
* 本结果所在的页码,从1开始 &bC}3D
* 2C+(":=}
* @return Returns the pageNo. ;\)=f6N
*/ 1|y$~R.H
publicint getP(){ L0h
G
return p; CVKnTEs
} .5tg4%l
j^u[F"
/** +GNWF%
zN
* if(p<=0) p=1 KHj6Tg;)
*
~Nh&.a
* @param p 7|D|4!i2Y
*/ <4?*$
publicvoid setP(int p){ =d20Xa
if(p <= 0) R ZcH+?7
p = 1; ?g}kb
this.p = p; !QC<n/
} 2)LX^?7R
2>y:N.
/** |+E KF.K
* 每页记录数量 3XVk#)lw
*/ @&R1wr1>I5
publicint getNum(){ C!UEXj`l9
return num; #vnT&FN0[
} j 2}v}
}$)&{d G
/** 8 lS($@@{
* if(num<1) num=1 5RhF+p4
*/ =P_fv
publicvoid setNum(int num){ qC
j*>D
if(num < 1) 6VR18Y!y
num = 1; dq8+m(7k
this.num = num; {[3YJkrM
} Mvof%I
]gP8?s|
/** 'O "kt T
* 获得总页数 b>=7B6 Aw
*/ &:auB:b
publicint getPageNum(){ G2@KI-
return(count - 1) / num + 1; Y+qus
} n0FYfqH
qBiyGlu4
/** q!2<=:f
* 获得本页的开始编号,为 (p-1)*num+1 SQIdJG^:
*/ 0WS|~?OR@
publicint getStart(){ ]PVto\B=
return(p - 1) * num + 1; I=b'j5c
} ?z"YC&Tp
9RcM$[~
/** 8_awMVAy
* @return Returns the results. "i''Ui\H
*/ `t9.xB#Z
publicList<E> getResults(){ X8.y4{5
return results; UC#"=Xd4
} ReqE?CeV
a(!3Afi
public void setResults(List<E> results){ UFk!dK+
this.results = results; w=$'Lt!
} k) 3s?
*s36OF!
public String toString(){ 500>
CBL0O
StringBuilder buff = new StringBuilder %OFj
,N;v~D$Y
(); x {vIT- f
buff.append("{"); .SBc5KX
buff.append("count:").append(count); My0!=4Any
buff.append(",p:").append(p); tKX}Ok:V%
buff.append(",nump:").append(num);
BUV/twU)
buff.append(",results:").append J2=*-O:
#\0TxG5'QA
(results); ;6zPiaDQ
buff.append("}"); ^Bn1;
return buff.toString(); P_mi)@
} p*!q}%U
_Z0\`kba+
} oB3q AP
6w@,I;
0ovZ&l