Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 G5]1s
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 aw}+'(?8]
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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 <rK=9"$y(t
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 :h";c"
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分页支持类: rPq<Xb\
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java代码: {w`:KR6o7
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package com.javaeye.common.util; \k&1*b?h
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import java.util.List; |#5 e|z5(
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publicclass PaginationSupport { 2DMrMmLI
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publicfinalstaticint PAGESIZE = 30; 5)lW
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privateint pageSize = PAGESIZE; jv}=&d
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privateList items; `"y{;PCt_
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privateint totalCount; K%,$ V,#
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privateint[] indexes = newint[0]; dhR(_
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privateint startIndex = 0; QdDtvJLf
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public PaginationSupport(List items, int ^Qh-(u`
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totalCount){ A'eAu
setPageSize(PAGESIZE); t;Wotfc[#0
setTotalCount(totalCount); -gKpL\
setItems(items); h-'wV${b
setStartIndex(0); 3;BvnD7
} VbxAd 2')
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public PaginationSupport(List items, int By)3*<5a_
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totalCount, int startIndex){ Xm[Czd]%
setPageSize(PAGESIZE); Hql5oA
setTotalCount(totalCount); `facFt[\
setItems(items); {fG|_+tl3o
setStartIndex(startIndex); -Z?Ck!00
} F RH&B5w
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public PaginationSupport(List items, int 44C+h
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totalCount, int pageSize, int startIndex){ >rRf9wO1l
setPageSize(pageSize); r>3^kL5UI
setTotalCount(totalCount); TU%"jb5
setItems(items); 0^\/ERK
setStartIndex(startIndex); QAaF@Do
} ;6<zjV7}
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publicList getItems(){ k&DGJ5m$.
return items; !`C?nY
} /VtlG+dLl
w4OW4J#
publicvoid setItems(List items){ UA0tFeH
this.items = items; 5^|"_Q#:
} LkaG[^tfN
rUFFF'm\*a
publicint getPageSize(){ "#XtDpGk
return pageSize; jT"r$""1d
} @DCJ}hud
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publicvoid setPageSize(int pageSize){ 4hNwKe"Ki
this.pageSize = pageSize; aiR5/
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} .wri5
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publicint getTotalCount(){ 8m7eaZ
return totalCount;
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} zv9MHC
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publicvoid setTotalCount(int totalCount){ &
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if(totalCount > 0){ _sm;HH7'*
this.totalCount = totalCount; xK!DtRzsA
int count = totalCount / C"9"{
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pageSize; fv5C!> t
if(totalCount % pageSize > 0) S2}Z&X(
count++; ZV#$Z
indexes = newint[count]; 4@~a<P#
for(int i = 0; i < count; i++){ afy/K'~
indexes = pageSize * SEU\}Ni{
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} SauHFl8?
}else{ {tmKCG
this.totalCount = 0; ,]U[W
} l qXc
} Ge~,[If+
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publicint[] getIndexes(){ D@5s8xv
return indexes; THr8o V5
} c'~[!,[b<
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publicvoid setIndexes(int[] indexes){ Q(blW
this.indexes = indexes; -=>U
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} () <`t}FQ
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publicint getStartIndex(){ skK*OO2-
return startIndex; kyK'
} sr4jQo
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publicvoid setStartIndex(int startIndex){ 6mAB(X^+
if(totalCount <= 0) 9^p32G
this.startIndex = 0; 9c6 '
elseif(startIndex >= totalCount) =1Ri]b
this.startIndex = indexes O*ImLR)i+s
1 M=
[indexes.length - 1]; 3~:0?Zuq
elseif(startIndex < 0) t,1in4sN
this.startIndex = 0; "kU>~~y,
else{ hLSTSD}
this.startIndex = indexes G#'Q~N
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[startIndex / pageSize]; Vl4Z_viNH
} ?^Pq/VtZ
} KZW'O
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publicint getNextIndex(){ db^aL8
int nextIndex = getStartIndex() + @$EjD3Z-
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pageSize; 8Kk3_ y
if(nextIndex >= totalCount) SF"#\{cjj
return getStartIndex(); 2aFT<T0
else ;Na^]32
return nextIndex; PaxK^*
} AzxL%,_
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publicint getPreviousIndex(){ x'zihDOI
int previousIndex = getStartIndex() - 0s)cVYppe
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pageSize; jp%+n
if(previousIndex < 0) RrKfTiK H
return0; p %L1uwLG
else .hc|t-7f
return previousIndex; ?Q;kZmQl
} _/ct=
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} \WiqN*ZF
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抽象业务类 }'DC
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java代码: C`3V=BB
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/** L
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* Created on 2005-7-12 IX"ZS
*/ AvyQ4xim+
package com.javaeye.common.business; 6$;L]<$W>
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import java.io.Serializable; B>sCP"/uV
import java.util.List; -%>8.#~G
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import org.hibernate.Criteria; D DQs42[
import org.hibernate.HibernateException; sw [oQ!f
import org.hibernate.Session; 9LH=3Qt
import org.hibernate.criterion.DetachedCriteria; m"<4\;GK
import org.hibernate.criterion.Projections; 1B6C<cL:sU
import 8~.iuFp
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org.springframework.orm.hibernate3.HibernateCallback; Q! Kn|mnN
import |O57N'/
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org.springframework.orm.hibernate3.support.HibernateDaoS |MR%{ZC^i
3R'.}^RN
upport; J `YnT
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import com.javaeye.common.util.PaginationSupport; Cy<T Vk8
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public abstract class AbstractManager extends K*HCFqrU"
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HibernateDaoSupport { XO 0>t{G
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privateboolean cacheQueries = false; CdDH1[J
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privateString queryCacheRegion; o>0O@NE
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publicvoid setCacheQueries(boolean T_uNF8Bh
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cacheQueries){ 8n;kK?
this.cacheQueries = cacheQueries; 2dXU0095
} ^I@ey*$
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publicvoid setQueryCacheRegion(String `<S/?I8
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queryCacheRegion){ $<
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this.queryCacheRegion = ftO+.-sm<
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queryCacheRegion; &1*4%N@'
} \P*PjG?R
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publicvoid save(finalObject entity){ +xn&K"]:3
getHibernateTemplate().save(entity); iP2U]d~M
} W"W@WG9X0
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publicvoid persist(finalObject entity){ {`+bW"9
getHibernateTemplate().save(entity); ;>inT7?3|
} 9@(O\ xr
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publicvoid update(finalObject entity){ Bh\
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getHibernateTemplate().update(entity); BXT80a\
} n"XdHW0
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publicvoid delete(finalObject entity){ 8o!
getHibernateTemplate().delete(entity); )WaX2uDA?
} _u#/u2<
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publicObject load(finalClass entity, <dq,y>
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finalSerializable id){ 'wCS6_K
return getHibernateTemplate().load -$AjD?;
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(entity, id); uOyLC<I/
} )o05Vda
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publicObject get(finalClass entity, p#ZMABlE,P
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finalSerializable id){ ;[?J5X,
return getHibernateTemplate().get F;cI0kP=>
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(entity, id); $~
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} "
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publicList findAll(finalClass entity){ j09mI$2y67
return getHibernateTemplate().find("from 5Z^$`$/.v#
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" + entity.getName()); 38"8,k
} O{;M6U8C\
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publicList findByNamedQuery(finalString M\:"~XW
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namedQuery){ VFe-#"0ZO
return getHibernateTemplate d[~au=b
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().findByNamedQuery(namedQuery); o%kSR ]V|
} gg lNpzj
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publicList findByNamedQuery(finalString query, $=\oJ-(!@S
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finalObject parameter){ OU0xZ=G
return getHibernateTemplate ,\|n=T,
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().findByNamedQuery(query, parameter); NTv#{7q
} wo,""=l
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publicList findByNamedQuery(finalString query, `77;MGg*
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finalObject[] parameters){ V/QTYy1
return getHibernateTemplate p[ks} mca@
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().findByNamedQuery(query, parameters); sW>P-
} ?TL2'U|M
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publicList find(finalString query){ Pur"9jHa4
return getHibernateTemplate().find Hl%+F0^?
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(query); y>)mSl@1y
} w3>Y7vxiz`
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publicList find(finalString query, finalObject TzD:bKE&
o=a:L^nt,
parameter){ 7?kXgR[#d
return getHibernateTemplate().find ~NNaLl
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(query, parameter); 9m<X-B&P
} kMwIuy
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public PaginationSupport findPageByCriteria ~Mg8C9B?%3
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(final DetachedCriteria detachedCriteria){ 73!
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return findPageByCriteria B}TInI%H
b&U5VA0=1
(detachedCriteria, PaginationSupport.PAGESIZE, 0); dK=D=5r,
} rsIt~w
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public PaginationSupport findPageByCriteria S 2{ ?W
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(final DetachedCriteria detachedCriteria, finalint K8 Kz
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startIndex){ 1xFhhncf
return findPageByCriteria iTKG,$G
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(detachedCriteria, PaginationSupport.PAGESIZE, IdQwLt
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startIndex); EmBfiuX
} B?/12+sR
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public PaginationSupport findPageByCriteria Z3u""oM/
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(final DetachedCriteria detachedCriteria, finalint l*m]2"n]
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pageSize, *y[~kWI
finalint startIndex){ H)?" 8 s
return(PaginationSupport) ]0/~6f
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getHibernateTemplate().execute(new HibernateCallback(){ \fQgiX
publicObject doInHibernate 1W6n[Xg
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(Session session)throws HibernateException { 7W>}7
Criteria criteria = v J,xz*rc`
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detachedCriteria.getExecutableCriteria(session); $[^ KCNB
int totalCount =
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((Integer) criteria.setProjection(Projections.rowCount -*]9Ma<wa
[{.\UkV@
()).uniqueResult()).intValue(); +kdU%Sm
criteria.setProjection Ff1M~MhG
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(null); v#AO\zYKd
List items = `P)64So-1
< 8W:ij.`
criteria.setFirstResult(startIndex).setMaxResults Liz6ob
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(pageSize).list(); TTw~.x,
PaginationSupport ps = }@Ll!,
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new PaginationSupport(items, totalCount, pageSize, 1{uDHB
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startIndex); V.OoZGE>]
return ps; Nr*ibtz|D
} y&O_Jyg<
}, true); zs]>XO~Jg
} 0UAr}H.:
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public List findAllByCriteria(final ph$&f0A6Xc
/[)P^L`
DetachedCriteria detachedCriteria){ |RbUmuj
return(List) getHibernateTemplate "~,(Xa3x
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().execute(new HibernateCallback(){ g275{2G9
publicObject doInHibernate X|QX1dl
w|U@jr*H]
(Session session)throws HibernateException { TJGKQyG$L
Criteria criteria = -iZ js
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detachedCriteria.getExecutableCriteria(session); *dn-,Q%`
return criteria.list(); 8aM%
9OU
} SUQ}^gn]
}, true); 66y ,{t
} f~(^|~ZT
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public int getCountByCriteria(final IEKX'+t'
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DetachedCriteria detachedCriteria){ C(Bar#
Integer count = (Integer) @5nkI$>3z
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getHibernateTemplate().execute(new HibernateCallback(){ fqp7a1qQl
publicObject doInHibernate FK,r<+h
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(Session session)throws HibernateException { ]H@uuPT!
Criteria criteria = (G b{ckzs
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detachedCriteria.getExecutableCriteria(session); '&L
return [>QsMUvak
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criteria.setProjection(Projections.rowCount XzR WY\x
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()).uniqueResult(); [}g5Z=l
} .dq.F#2B;
}, true); 5<'Jd3N{&
return count.intValue(); MyR\_)P?
} <P)%Ms
} orN2(:Ct7
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用户在web层构造查询条件detachedCriteria,和可选的 o~z.7q
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 AT8,9
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PaginationSupport的实例ps。 5;%xqdD
er}'}n`@q
ps.getItems()得到已分页好的结果集 `1}yB
ps.getIndexes()得到分页索引的数组 m`w6wz
ps.getTotalCount()得到总结果数 4w
ps.getStartIndex()当前分页索引 SodW5v a
ps.getNextIndex()下一页索引 ToCfLJ?{
ps.getPreviousIndex()上一页索引 YH6K-}
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 { l~T~3/i
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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 t5[JN:an
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一下代码重构了。 J!qEj{
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我把原本我的做法也提供出来供大家讨论吧: .oOt(K+
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首先,为了实现分页查询,我封装了一个Page类: a*@Z^5f
java代码: 60gn`s,,
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/*Created on 2005-4-14*/ CKK5+
package org.flyware.util.page; W;*vcbP
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/** #nL0Hx7]E
* @author Joa YmF(o
* 2QD
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*/ T</gWW
publicclass Page { cnO4NUDv
HCZ%DBU96
/** imply if the page has previous page */ iONql7S @
privateboolean hasPrePage; y3$\ m
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/** imply if the page has next page */ `9)2nkJk'z
privateboolean hasNextPage;
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Hw3E S
/** the number of every page */ , 0ja _
privateint everyPage; ?~9X:~6\
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/** the total page number */ 3m9E2R,
privateint totalPage; B}bNl 7
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/** the number of current page */ :Gk~FRA|
privateint currentPage; |iThgq_\z
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/** the begin index of the records by the current `
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query */ `t"Kq+
privateint beginIndex; 7Et(p'
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/** The default constructor */ ^ @cX0_
public Page(){ 9%veUvY
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} 1e%Xyqb
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/** construct the page by everyPage Y&%0 eI!
* @param everyPage UYLI>XSd
* */ dXN&<Q,
public Page(int everyPage){ ?XrTZ{5'
this.everyPage = everyPage; {x$#5PW
} 6XqO'G
JH,+F
/** The whole constructor */ 5,fzB~$TX(
public Page(boolean hasPrePage, boolean hasNextPage, b .@dUuKz-
K~N[^pF
H*<dte<
int everyPage, int totalPage, U}TQXYAg
int currentPage, int beginIndex){ wYM{x!D
this.hasPrePage = hasPrePage; J~6*d,Ry`
this.hasNextPage = hasNextPage; :36^^Wm
this.everyPage = everyPage; <o`]wOrl
this.totalPage = totalPage; N_}Im>;!
this.currentPage = currentPage; !I$RE?7eY
this.beginIndex = beginIndex; dRC+|^rSC
} Ee| y[y,
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/** @1X1E 2:
* @return [#H8Mb+7
* Returns the beginIndex. D]y.!D{l2
*/ 9a,CiH%@
publicint getBeginIndex(){ [X\2U4
return beginIndex; b&&'b)
} w%na n=
cE?J]5#^
/** yx4c+(J^8
* @param beginIndex cV,URUD
* The beginIndex to set. ;pYk+r6 Cr
*/ qN(;l&Q
publicvoid setBeginIndex(int beginIndex){ pm|]GkM
this.beginIndex = beginIndex; 3j#F'M)s{
} *2hzReM
Cl=ExpX/O
/** m#P&Yd4T
* @return )`0 j\
* Returns the currentPage. kv2:rmv
*/ 1Tkz!
publicint getCurrentPage(){ R'U(]&e.j
return currentPage;
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`
} <ZEll[0L
CdjGYS
/**
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* @param currentPage ->UrWW^
* The currentPage to set. &-tf/qJ
*/ zc5_;!t
publicvoid setCurrentPage(int currentPage){ 1Zzw|@#>o
this.currentPage = currentPage; X[}%iEWzT
} ponvi42u
(d\bSo$]
/** Vh&KfYY
* @return |M&/(0
* Returns the everyPage. [sRQd;+
*/ 6IH^rSUSK
publicint getEveryPage(){ Z]CH8GS~<
return everyPage; h[?28q$
} +/'jX?7x%
nz+KA\iW
/** S{06bLXU"
* @param everyPage ,\IZ/1
* The everyPage to set. (Nf.a4O
*/ it@s(1EO#
publicvoid setEveryPage(int everyPage){ c{q`uI;O
this.everyPage = everyPage; W1z5|-T
} =nl,5^
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/** oB@C-(M
* @return h
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* Returns the hasNextPage. {I
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*/ g*uO
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publicboolean getHasNextPage(){ 1d6pQ9 N
return hasNextPage; |ouk;r24V
} Uw!v=n3#!
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/** 8jk*N
* @param hasNextPage J\BdC];
* The hasNextPage to set. =W=%!A\g
*/ #</yX5!V
publicvoid setHasNextPage(boolean hasNextPage){ xUUp?]9y
this.hasNextPage = hasNextPage; C}Q2UK-:
} 2I
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/** K.SHY!U}
* @return l/5/|UE9
* Returns the hasPrePage. `N0E;=g
*/ ~czt=
publicboolean getHasPrePage(){ DDEn63{
return hasPrePage; [iD!!{6+
} jn'8F$GU
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/** "Q( 8FF
* @param hasPrePage m,b<b91
* The hasPrePage to set. ~[{| s')
*/ 9azPUf)
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publicvoid setHasPrePage(boolean hasPrePage){ K;~dZ
this.hasPrePage = hasPrePage; &2DW
} 3ba"[C|
l`k3!EZDS
/** C*$/J\6xy
* @return Returns the totalPage. >4c 1VEi
* 4^r}&9C~
*/ ME.LS2'n
publicint getTotalPage(){ }z[se)s
return totalPage; Ic*Q(X
} sq%f%?(V
7%tn+
/** &fcRVku
* @param totalPage U"Y$7~
* The totalPage to set. QB7<$Bp
*/ {!w]t?h
publicvoid setTotalPage(int totalPage){ l6~eb=u;9g
this.totalPage = totalPage; p5*Y&aKj
} $FoNEr&q
9"rATgN1
} px*MOHq K
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5R4 dN=L*1
9M6&+1XE
8447hb?W$
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 @RC_Ie=#)
A U](pXK;
个PageUtil,负责对Page对象进行构造: LakP'P6`E
java代码: lxeolDl
t?s1@}G^
})" : F
/*Created on 2005-4-14*/ c09 uCito
package org.flyware.util.page; hE;
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import org.apache.commons.logging.Log; \%)p7PNY
import org.apache.commons.logging.LogFactory; ojaZC,}
B\Uj
/** gP}M\3-O
* @author Joa +mY(6|1
* p(Sfw>t(
*/ lr1i DwZV
publicclass PageUtil { [W2k#-%G
UwLa9Dn^
privatestaticfinal Log logger = LogFactory.getLog ;3w W)gL1
yk=H@`~!
(PageUtil.class); /q=<OEC
^71sIf;+
/** qU"+0t4
* Use the origin page to create a new page $V[ob
* @param page 76
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* @param totalRecords M8h9i2
* @return c9Cp!.#*E
*/ &0
@2JS/!
publicstatic Page createPage(Page page, int I*X|pRD
+2vcUy
totalRecords){ +iXA|L9=
return createPage(page.getEveryPage(), 5yry$w$G)
<+6)E@Y
page.getCurrentPage(), totalRecords); "G<^@v9
} ^P[-HA|
p%}oo#%J
/** ZY83,:<
* the basic page utils not including exception *_ "j"{
pvX\kX3}
handler 6,!]x>B
* @param everyPage >Zr`9$i
* @param currentPage :5ji.g* 0
* @param totalRecords r!;NH3 *
* @return page !a
/
*/ O:1YG$uKa
publicstatic Page createPage(int everyPage, int B"G;"X
k'm!|
currentPage, int totalRecords){ HxkhlNB
everyPage = getEveryPage(everyPage);
hp)3@&T
currentPage = getCurrentPage(currentPage); #q%&,;4
int beginIndex = getBeginIndex(everyPage, c(o8uWn
oM< 9]jK}
currentPage); IkD\YPL;
int totalPage = getTotalPage(everyPage, .7oz
Mq$e5&/
totalRecords); BsxQW`>^y
boolean hasNextPage = hasNextPage(currentPage, f;QWlh"9
NbSwn}e_
totalPage); =x=#Etj|
boolean hasPrePage = hasPrePage(currentPage); |S/nq_g]
=l
{>-`:
returnnew Page(hasPrePage, hasNextPage, 5{{u #W%=
everyPage, totalPage, %KqXtc`O
currentPage, `*WR[c
u{HB5QqK
beginIndex); 4-sUy
} t;
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privatestaticint getEveryPage(int everyPage){ 9Czc$fSSt
return everyPage == 0 ? 10 : everyPage; sI#K01;"
} cBU>/
zIp
F$d`Umqs;P
privatestaticint getCurrentPage(int currentPage){ /']Gnt G.
return currentPage == 0 ? 1 : currentPage; ?L'ijzP
} 2nk}'HBe
pm^[ve
privatestaticint getBeginIndex(int everyPage, int @zE_fL
CB|Z~_Bm
currentPage){ gVA$P
return(currentPage - 1) * everyPage; KN5.2pp
} {eS!cZJ
oveW )~4
privatestaticint getTotalPage(int everyPage, int 7GpSWM6
o: qB#8X
totalRecords){ \T>f+0=4
int totalPage = 0; :h" Y >1P
XBCz\f
if(totalRecords % everyPage == 0) ZfS-W&6Z
totalPage = totalRecords / everyPage; 6:@tHUm
else uS3J^=>@(a
totalPage = totalRecords / everyPage + 1 ; [@Y?'={qE
7|*|xLrVY
return totalPage; ]^R;3kU4Q
} Jgb{Tl:r
'\P6NszY~
privatestaticboolean hasPrePage(int currentPage){ VDBP]LRF
return currentPage == 1 ? false : true; 8MV=?
} 'xhX\?mD
a>6!?:Rj
privatestaticboolean hasNextPage(int currentPage, *SLv$A
5s`NR<|2L
int totalPage){ m%ak ]rv([
return currentPage == totalPage || totalPage == ]QRhTz
qpFFvZ
W
0 ? false : true; >tYptRP
} A6=
Um%T
c1Xt$[_
! p458~|
} qa2QS._m
#X`j#"Ov2(
%
?@PlQ
"2$C_aE
&K/5AH"q
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。 _=}Efy7
t /1KKEZM
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 }hhDJ_I5M
:voQ#f=
做法如下: :k#Y|(
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 }qRYXjS
5l}v
的信息,和一个结果集List:
PohG y
java代码: ?=$a6o
&dH/V-te
y>UM~E
/*Created on 2005-6-13*/ _}8O15B|
package com.adt.bo; PH^AT<U:T
k& 2U&
import java.util.List; -$>R;L
LY-fp+
import org.flyware.util.page.Page; ?l
&S:`
L
r1}YN<+,s
/** W^Wr
* @author Joa =bi:<%"
*/ g kT`C
publicclass Result { cR*D)'/tl
~K 5eO-
private Page page; !X*+Ct^
Vr+X!DeY
private List content; l q~^&\_#
oqc89DEbJ
/** Mpzt9*7R
* The default constructor }.>( [\q
*/ @2na r<
public Result(){ g ]e^;
super(); :<r.n
"
} IQAV`~_G
;`p+Vs8C
/** |#^wYZO1U
* The constructor using fields iimTr_TEt
* C4Z}WBS(
* @param page 9nN$%(EO5;
* @param content _0Qp[l-
*/ d="Oge8
public Result(Page page, List content){ Dp3&@M"^yY
this.page = page; <l opk('7
this.content = content; P-o/ax
} U-&dn%Sq
|3<tDq@+
/** W<_9*{|E;
* @return Returns the content. W$>srdG0$
*/ q$L=G
publicList getContent(){ >x]b"@Hkw
return content; 3#<b!Yz
} ?%-VSL>$w=
Up*1j:_O
/** [#hpWNez(>
* @return Returns the page. "%ou'\}
*/ @-qS[bV
public Page getPage(){ VRV*\*~$
return page; 3M\~#>
} @TBcVHy
# bc$[%_
/** iI\bD
* @param content pBl'SQccp
* The content to set. awxzP*6
*/ O<[h
public void setContent(List content){ }tJRBb
this.content = content; n,/eT,48`
} }-jS0{i
[CxnGeKK
/** Mm7;'Zbg
* @param page .
7*k}@k
* The page to set. q$RJ3{Sf
*/ 6Y9F U
publicvoid setPage(Page page){ ,\8F27
this.page = page; a@4
Zx
} m.!n|_}]
} mUSrC U_}
mqe83 k%
Bu_/yKW
y.vYT{^
^F\RM4|,
2. 编写业务逻辑接口,并实现它(UserManager, l Oxz&m
n@%Q 2_
UserManagerImpl) {&7%wZ"t_
java代码: M:TN^ rA|
NN>E1d=
rG[iEY
/*Created on 2005-7-15*/ m-T@Og
package com.adt.service; >2vUFq`H
QiO4fS'~W
import net.sf.hibernate.HibernateException; r:N =?X`N
LL% Aw)Q`
import org.flyware.util.page.Page; 1'Sr0
oEd3
n1!hfu7@s
import com.adt.bo.Result; 0ndk=V
3T1t !q4/5
/** m{#?fR=9
* @author Joa ;|yd}q=p
*/ X;:qnnO
publicinterface UserManager { P'}WmE'B}F
2:[
-
public Result listUser(Page page)throws J:D{5sE<|
[7Fx#o=da
HibernateException; r{LrQ
U)v){g3w)
} ?`T0zpC
|)5xm N]
Z01BzIsR
oyw*Z_ 9~
a%nksuP3
java代码: n1XJuc~
mH`K~8pRg
l 7T@<V
/*Created on 2005-7-15*/ j(xVbUa
package com.adt.service.impl; 4e`GMtp
"kb[}r4?
import java.util.List; ~?6M4!u
~W/|RP7S
import net.sf.hibernate.HibernateException; IN^dJ^1+
LI~ofCp
import org.flyware.util.page.Page; ^+J3E4
import org.flyware.util.page.PageUtil; =`st1K
Xmb001
import com.adt.bo.Result; qQN|\u+co
import com.adt.dao.UserDAO; %m/W4Nk
import com.adt.exception.ObjectNotFoundException; }R&5Ye
import com.adt.service.UserManager; -tPia=^
p[LPi5
/** VZz>)Kz:
* @author Joa @"h@4q/W
*/ !=)b2}e/>
publicclass UserManagerImpl implements UserManager { [[XbKg`"?
h/goV
private UserDAO userDAO; {)`tN&\
XfZ^,'z
/** }+@GgipyO.
* @param userDAO The userDAO to set. ?zpN09e
*/ 8el\M/u{
publicvoid setUserDAO(UserDAO userDAO){ uD=FTx
this.userDAO = userDAO; *`]#ntz9
} x*#9\*@EI
N\{{:<Cp\
/* (non-Javadoc) <sncW>?!~
* @see com.adt.service.UserManager#listUser ?y/LMja
$eu-8E'
(org.flyware.util.page.Page) ,@Fde=Lw
*/ vk><S|[n
public Result listUser(Page page)throws Mn<#rBE B
e+~Q58oD
HibernateException, ObjectNotFoundException { L,\wB7t
int totalRecords = userDAO.getUserCount(); (O!Q[WLS
if(totalRecords == 0) dje}CbZ
throw new ObjectNotFoundException \+#>XDD
{t%Jc~p{
("userNotExist"); fbrCl!%P
page = PageUtil.createPage(page, totalRecords); `b:yW.#w3l
List users = userDAO.getUserByPage(page); Z#vU~1W
returnnew Result(page, users); 7Zw.mM!i
} 'eYM;\%('
bXNM.K
} #S|DoeFs
o%SD\zk
N|-'Fu
4:0y\M5u
SJ8CBxA
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 HU1ZQkf
BG9.h!
询,接下来编写UserDAO的代码: h0z>dLA#2
3. UserDAO 和 UserDAOImpl: JwNB)e
D
java代码: WV&grG|
V48o+ O
PRi1 `%d
/*Created on 2005-7-15*/ Dt~ |)L+
package com.adt.dao; /%{Qf
"8l&m6`U-
import java.util.List; f&2f8@
eqQ=HT7J
import org.flyware.util.page.Page; *=b36M
|aX1PC)o_
import net.sf.hibernate.HibernateException; WNO!6*+
zDohp 5,
/** D!WyT`T
* @author Joa ;^DG P
*/ |r<#>~*
publicinterface UserDAO extends BaseDAO { + t7n6
?,z/+/:
publicList getUserByName(String name)throws ad#4W0@S
Oe)B.{;Ph
HibernateException; 0[In5I I
61pJVOe
publicint getUserCount()throws HibernateException; _Squ%z:D
b-OniMq~
publicList getUserByPage(Page page)throws GX#SCZ&}C
y!u=]BE
HibernateException; *LOUf7`
1+ib(MJ<:#
} ~cH3RFV
5DS'22GW`
htu(R$GSM
$d\>^Q
2H9;4>ss
java代码: )WH;G:$&"
*-`-P
[BZA1,
/*Created on 2005-7-15*/ <x[CL,Zg7
package com.adt.dao.impl; ,)35Vi;.
?Rd{`5.D
import java.util.List; VdOcKP.
; S~
import org.flyware.util.page.Page; oY<R[NYKu
2Fc>6]:*
import net.sf.hibernate.HibernateException; SUN!8
qFA
import net.sf.hibernate.Query; cnraNq1
EPiZe-
import com.adt.dao.UserDAO; jBMGm"NE
3R&
FzLs
/** []l2
`fS#
* @author Joa .C\##
*/ cH48)
public class UserDAOImpl extends BaseDAOHibernateImpl b]6@
O8
\(`8ng]vs
implements UserDAO { eufGU)M
b <z)4
/* (non-Javadoc) h/pm$9A
* @see com.adt.dao.UserDAO#getUserByName %4,v2K
`'G1"CX
(java.lang.String) DIBoIWSuR
*/ AlA:MO]NM
publicList getUserByName(String name)throws f)19sjAJk
~A@HW!*Z@
HibernateException { lPZYd8
String querySentence = "FROM user in class zff<#yK1
QWI)Y:<K/
com.adt.po.User WHERE user.name=:name"; s"JD,gm$
Query query = getSession().createQuery 0Zh]n;S3m
~UNK[
(querySentence); 1n!xsesSc
query.setParameter("name", name); 4A)@,t9+
return query.list(); oM(8'{S=
} }l7@:ezZZ7
:^rt8>~
/* (non-Javadoc) 0b(x@>
* @see com.adt.dao.UserDAO#getUserCount() Gy F
*/ m[DCA\Mo@
publicint getUserCount()throws HibernateException { 9>k_z&<
int count = 0; 4l'`q+^-
String querySentence = "SELECT count(*) FROM +SNjU"x
g\]~H%2 ,
user in class com.adt.po.User"; Vrn+"2pdJ
Query query = getSession().createQuery ib- H
jJ8
!2F X l;
(querySentence); %R^*MUTx
count = ((Integer)query.iterate().next +3[8EM#g
b?K`DUju{0
()).intValue(); Ctx`b[&KXX
return count; 5@_kGoqd
} d1';d6.u\
} fJLY\
/* (non-Javadoc) #Q1}h
* @see com.adt.dao.UserDAO#getUserByPage ):lH
26ae|2?
(org.flyware.util.page.Page) l i)
5o
*/ UY(\T8
publicList getUserByPage(Page page)throws F R(k==pZ
hn=tSlte
HibernateException { -*$ s ;G#
String querySentence = "FROM user in class Zo<j"FG
8/k"A-m
com.adt.po.User"; gC+?5_=<
Query query = getSession().createQuery C7FxV2
T^icoX=c4
(querySentence); <,*3Av
query.setFirstResult(page.getBeginIndex()) 2(U;{;\n*
.setMaxResults(page.getEveryPage()); [`kk<$=,&
return query.list(); w+u1"
} NwyNl
L;-V Yo#
} an2Yluc;
<q&4Y+b
8d7 NESYl
Y_<-.?jf
G8&/Ic
至此,一个完整的分页程序完成。前台的只需要调用 x c]#8K
8"}8Nrb0
userManager.listUser(page)即可得到一个Page对象和结果集对象 8.:WMH`
-B&
Nou
的综合体,而传入的参数page对象则可以由前台传入,如果用 K\FLA_J
3sD|R{
webwork,甚至可以直接在配置文件中指定。 1:!H`*DU&
*yv@B!r
下面给出一个webwork调用示例: F:og :[
java代码: 01~
nC@;
SuXeUiK.[
'+\t,>nRkl
/*Created on 2005-6-17*/ x~Dj2F ]
package com.adt.action.user; JwQ/A[b
<$u\PJF7_^
import java.util.List; !/e*v>3u&
NFyKTA6
import org.apache.commons.logging.Log; GOOm] ]I
import org.apache.commons.logging.LogFactory; {y'4&vt<~
import org.flyware.util.page.Page; ey6ujV7!
Zs4NN2~
import com.adt.bo.Result; ?a-5^{{
import com.adt.service.UserService; k [LV^oEg
import com.opensymphony.xwork.Action; [HI$[:[
U!(es0rX
/** _2Mpzv
* @author Joa U C_$5~8p
*/ GvZ[3GT
publicclass ListUser implementsAction{ {isL<
2u$rloc$b
privatestaticfinal Log logger = LogFactory.getLog _F5*\tQ
&?$mS'P
(ListUser.class); Y]tbwOle
1|m%xX,[
private UserService userService; pp{2[>
m%=*3gH]&
private Page page; ;W]9DBAB
3W%j^nM
privateList users; s(KSN/
bz}-[W+
/* "8R
&c}
* (non-Javadoc) c]n"1YNm
* fW[ .Q0
* @see com.opensymphony.xwork.Action#execute() wr5v-_7r,
*/ G\o9mEzQ
publicString execute()throwsException{ J;=T"C&
Result result = userService.listUser(page); wh)F&@6 R!
page = result.getPage(); 0*_E'0L8e
users = result.getContent(); ,OERDWW|6
return SUCCESS; |Sm/s;&c6
} ]6F\a= J
f>bL
}L
/** A'.=SA2.Y
* @return Returns the page. H~^)^6)^T
*/ '4SDAa2f
public Page getPage(){ l))Q/8H
return page; ~oJ"si
} =^SxZ Bn
XDHi4i47`o
/** |-;VnC&UY
* @return Returns the users. 2WTOu x*
*/ s_a jA
publicList getUsers(){ \EsT1aT
return users; ~>HzAo9e
} UOk\fyD2[
x
FWhr#5,
/** >lfuo
* @param page lj UdsU w
* The page to set. l&}}Io$?@
*/ Inn{mmz
1
publicvoid setPage(Page page){ %pxO<O
this.page = page; *\(z"B
} * k<@
{0j_.XZ
/** zgH(/@P
* @param users U`lK'..
* The users to set. tU5uL.( O
*/ dt^h9I2O
publicvoid setUsers(List users){ fvcS=nRQv
this.users = users; ?^M,Mt
} *yaS^k\
:W5W
@8Y
/** _CfJ Kp)
* @param userService
g`%in
* The userService to set. cP D_=.&
*/ #fYB4.i~
publicvoid setUserService(UserService userService){ tc<uS%XT4^
this.userService = userService; 6pSi-FH
} N0.|Mb"?t
} E5$]0#jB
?3p7MjvZ
;AE-=/<
4(|yl^w
nYFrp)DLK
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, wD=]U@t`,
YZj*F-}
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 ;8eKAh
__2<v?\
么只需要: P RWb6
java代码: Qr9;CVW
%IX)+
Lp`
jx]P: ]
<?xml version="1.0"?> W*t]
d
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork BMy3tyO
@phVfP"M
1.0//EN" "http://www.opensymphony.com/xwork/xwork- 'gvR?[!t
n{FjFlX2=
1.0.dtd"> ocFk#FW
Sk E <V0
<xwork> }:Gs ,
sVK?sBs]
<package name="user" extends="webwork- o`,~#P|
IQRuqp KL
interceptors"> qyv=ot0"~F
w y|^=#k
<!-- The default interceptor stack name BtZ]~S}v
C/IF~<B
--> D]]wJQU2
<default-interceptor-ref
&cSVOsi
Ic9L@2m
name="myDefaultWebStack"/> ,-4NSli
F5Z,Jmi^M
<action name="listUser" d=PX}o^
_r*\ BM8y
class="com.adt.action.user.ListUser"> 80Dn!9j*
<param RqtBz3v
eHy UY&N/
name="page.everyPage">10</param> U}RBgPX!
<result &ASR2J
n7cy[%yT
name="success">/user/user_list.jsp</result> ch8a
</action> n4/Wd?#`
`8ac;b
</package> kFv*>>X`
t$18h2yOL
</xwork> d )O^(y1r
e@Lxduq
NOo?
(Jk&U8y
q(6.VU@
n^Ca?|}
,
这样就可以通过配置文件和OGNL的共同作用来对page对象设置初值 Y%.o
TB&
|oi+|r
了。并可以通过随意修改配置文件来修改每页需要显示的记录数。 #wI}93E
?T/]w-q>
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 YQn<CjZ8af
"XR=P>
xk
wlT8|
STp9Gh-
L~Gr,i
我写的一个用于分页的类,用了泛型了,hoho #h5lz%2g
QQM:[1;RT
java代码: kAQ(8xV
"lI-/G
V4:/LNq_]
package com.intokr.util; Io1j%T#ZT
eQuu\/z*H
import java.util.List; HIXAA?_eh=
P:"R;YCvE
/** s-$Wc)l
* 用于分页的类<br> dFm_"135
* 可以用于传递查询的结果也可以用于传送查询的参数<br> >R+-mP!nj
* cb|+6m~
* @version 0.01 ABN4kM>%
* @author cheng tk&AZb,sP
*/ ;xZ+1zmL0
public class Paginator<E> { _MBhwNBxZ
privateint count = 0; // 总记录数 {p +&Q|
privateint p = 1; // 页编号 >}+{;d
privateint num = 20; // 每页的记录数 Q":_\inF
privateList<E> results = null; // 结果 m/KaWrw/)
BNfj0e 5b
/** Ghgn<YG
* 结果总数 HwUaaK
*/ yQ$irS?
publicint getCount(){ ppyy0E^M
return count; ^M'(/O1
} {821e&r
CS7b3p!I
publicvoid setCount(int count){ u>*a@3$f
this.count = count; 'J,UKK\5
} LwC?t3n
r#sg5aS7O|
/** ~#r>@C
* 本结果所在的页码,从1开始 aZN?V}^+
* FDMQLx f
* @return Returns the pageNo. Z hfp>D
*/ Uwc%'=@
publicint getP(){ Lce,]z\_
return p; g\q .
} j&8YE7
e~]P _53
/** I-]G{
* if(p<=0) p=1 ]9oj,k
* -9b=-K.y
* @param p 16iTE-J_
*/ UPhO=G
publicvoid setP(int p){ *k{Llq
if(p <= 0) h`&TDB2
p = 1; ^?cu9S3
this.p = p; yu;EL>G_AY
} [V'c
)Te\6qM
/** <Wn~s=
* 每页记录数量 o?baiOkH
*/ '12m4quO
publicint getNum(){ S7+>Mk
return num; y\FQt];z)
} u$\.aWol
#{6VdWZ
/** T|~5dZL
* if(num<1) num=1 ~c EN=(Z~r
*/ 3H#,qug$
publicvoid setNum(int num){ La ?A@SD
if(num < 1) |
.jWz.c
num = 1; bpY*;o$~
this.num = num; ] &8em1
} 3r~8:F"g
(JbRhcg
/** lQIg0G/3
* 获得总页数 mB`HPT
*/ D?KLV_Op
publicint getPageNum(){ NS[ Z@@
return(count - 1) / num + 1; 7!M; ?Y
} gq('8*S
?p{-Yp*h
/** rmjuNy=(
* 获得本页的开始编号,为 (p-1)*num+1 =oSD)z1c?x
*/ +L 09^I
publicint getStart(){ Ftyxz&-4$p
return(p - 1) * num + 1; zZ[kU1Fyv
} D[>:az`
]9QXQH
/** ;6V~yB
* @return Returns the results. C6>_wl]
*/ G? SPz
publicList<E> getResults(){ )
gl{ x
return results; ug%7}&
} t]B`>SL3W
nAQ[
-NbW,
public void setResults(List<E> results){ c44s@E
this.results = results; YIN* '!N
} `Am|9LOT
t ]BG)]
public String toString(){
nS]e
StringBuilder buff = new StringBuilder ub?dfS9$_
pW[TufTa
(); q>%B @'
buff.append("{"); R*6TS"aL
buff.append("count:").append(count); / :$WOQ
buff.append(",p:").append(p); x1~AY/)v
buff.append(",nump:").append(num); IR"C?
buff.append(",results:").append 7^>~k}H
H ezbCwsx&
(results); gPn0-)<
buff.append("}"); +=W(c8~P
return buff.toString(); BiU>h.4=\(
} _#~D{91
j:
H7uh"/A
} HDhkg-QC
PVi;h%>Y
%|4Kak]:Q