Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 $8&HpX#h$
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 e,E;\x
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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 i:#R
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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 |xzqYu?o
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分页支持类: T
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java代码: &3{:h
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package com.javaeye.common.util; +bm2vIh$
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import java.util.List; ]CC=
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publicclass PaginationSupport { 7k6rhf7H
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publicfinalstaticint PAGESIZE = 30; NtTLvO6
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privateint pageSize = PAGESIZE; j<deTK;.
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privateList items; #bu`W!p}
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privateint totalCount; =|3L'cDC
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privateint[] indexes = newint[0]; dc&Qi_W
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privateint startIndex = 0; `*oLEXYN
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public PaginationSupport(List items, int =As'vt
0
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totalCount){ ,A6*EJ\w
setPageSize(PAGESIZE); q=?"0i&V
setTotalCount(totalCount);
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setItems(items); OD1ns
setStartIndex(0); 1}jE?{V*
} O1#rCFC|y
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public PaginationSupport(List items, int h y[_
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totalCount, int startIndex){ =m/2)R{
setPageSize(PAGESIZE); Mx r#
setTotalCount(totalCount); n@mUQ6
setItems(items); coLn};W2
setStartIndex(startIndex); >a4Bfnf"eI
} }p- %~Y
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public PaginationSupport(List items, int ^d=Z/d[
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totalCount, int pageSize, int startIndex){ -x_iqrB
setPageSize(pageSize); SiBbz4
setTotalCount(totalCount); 'xi..
setItems(items); I(7gmCV
setStartIndex(startIndex); WG}QLcP
} #ASu
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publicList getItems(){ \U-5&,fP
return items; sN?:9J8
} eqf~5/Z
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publicvoid setItems(List items){ eD(a
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this.items = items; 87>Qw,r
} /nmfp&@
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publicint getPageSize(){ $7bmUQ|
return pageSize; 0,3 ':Df
} p-6.:y
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publicvoid setPageSize(int pageSize){ bG&qgbN>
this.pageSize = pageSize; {vH8X(m
} vVf!XZF
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publicint getTotalCount(){ HWU{521
return totalCount; h
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} A&7jE:Ew
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publicvoid setTotalCount(int totalCount){ j w462h
if(totalCount > 0){ 7U7 i2 4
this.totalCount = totalCount; ;5l|-&{@*
int count = totalCount / SYwNx">Bq
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pageSize; .WPqK>79|
if(totalCount % pageSize > 0) !{XO#e
count++; j%h
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indexes = newint[count]; Ol@ZH_
for(int i = 0; i < count; i++){ [P,nW/H
indexes = pageSize * u^uG_^^,/
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i; ZSSgc0u^?
} TK>}$.c%+
}else{ lq5E?B
this.totalCount = 0; z~5'p(|@f
}
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} a+i+#*8wm
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publicint[] getIndexes(){ 7q=0]Hrg(D
return indexes; 463dLEd
} |{K:.x#^
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publicvoid setIndexes(int[] indexes){ y^rg%RV
this.indexes = indexes; A&'%ou
} _JDr?Kg
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publicint getStartIndex(){ ~-%A@Lt
return startIndex; 0}V'\=F454
} $C/Gn~k 5
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publicvoid setStartIndex(int startIndex){ (ce NVo&
if(totalCount <= 0) >cb
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this.startIndex = 0; sCl,]g0{
elseif(startIndex >= totalCount) "tARJW
this.startIndex = indexes cg%CYV)
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[indexes.length - 1]; ($W 5fbu
elseif(startIndex < 0) -c@ 5qe>
this.startIndex = 0; Ke'2"VkQt
else{ !y?hn$w0
this.startIndex = indexes tV9C33
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[startIndex / pageSize]; <UdD@(iZ#
} ?<QFW#:)
} %#a%Luq
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publicint getNextIndex(){ Nk4_!
int nextIndex = getStartIndex() + 5.#9}]
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pageSize; X~3P?O]kFv
if(nextIndex >= totalCount) 4/WCs$
return getStartIndex(); :,,y63-f4
else -Wk"o?}q
return nextIndex; hp4(f W
}
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publicint getPreviousIndex(){
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int previousIndex = getStartIndex() - J*X.0&Toc
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pageSize; nk
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if(previousIndex < 0) y03a\K5[KQ
return0; x{V>(d'p
else s'Gy+h.
return previousIndex; SVh4)}.x
} 5q`)jd !*)
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} "]Dzc[Vp
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抽象业务类 <9tG_
java代码: e*6` dz@
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/** uN3J)@;_
* Created on 2005-7-12 _hL4@C
*/ TbAdTmW
package com.javaeye.common.business; pY>-N
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import java.io.Serializable; 0a6z"K}
import java.util.List; ]mo<qWRc>p
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import org.hibernate.Criteria; jI<WzvhYG
import org.hibernate.HibernateException; |Umfq:W`y_
import org.hibernate.Session; qgsE7 ]
import org.hibernate.criterion.DetachedCriteria; dS_)ll.6z
import org.hibernate.criterion.Projections; A""*vqA
import L9?/ -@M
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org.springframework.orm.hibernate3.HibernateCallback; lT!$\E$1
import <O)X89dFM
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org.springframework.orm.hibernate3.support.HibernateDaoS NV(4wlh)y
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upport; C*6)Ut '
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import com.javaeye.common.util.PaginationSupport; *([)X2A@+
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public abstract class AbstractManager extends Il`k]X M
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HibernateDaoSupport { >AX~c
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privateboolean cacheQueries = false; #iU8hUbo
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privateString queryCacheRegion; pH l2!{z
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publicvoid setCacheQueries(boolean /j69NEl
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cacheQueries){ OC>_=i$'
this.cacheQueries = cacheQueries; #!u51P1
} |}p}`Mb)a
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publicvoid setQueryCacheRegion(String Z*9]:dG:!
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queryCacheRegion){ ]F*a PV
this.queryCacheRegion = ~z
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queryCacheRegion; {+6D-rDw
} T'b/]&0Tio
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publicvoid save(finalObject entity){ dbuJ~?D,
getHibernateTemplate().save(entity); .F$|j1y
} =i^<a7M~
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publicvoid persist(finalObject entity){ J1]w*2
getHibernateTemplate().save(entity); UUMdZ+7
} g;!@DVF$
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publicvoid update(finalObject entity){ r2GK_$vd
getHibernateTemplate().update(entity); z'oiyXEE3
} (YYj3#|
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publicvoid delete(finalObject entity){ :IVk_[s
getHibernateTemplate().delete(entity);
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} 8 ih;#I=q
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publicObject load(finalClass entity, EwD3d0udL
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finalSerializable id){ "rx^M*"
return getHibernateTemplate().load "\/^/vn?
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(entity, id); jkF+g$B
}
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publicObject get(finalClass entity, MZ5Y\-nq\
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finalSerializable id){ 6hM]%
return getHibernateTemplate().get iO*`(s
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(entity, id); wMz-U- z
} OpK.Lsd0y
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publicList findAll(finalClass entity){ +%Lt". o
return getHibernateTemplate().find("from @q&|MMLt
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" + entity.getName()); ,jRcl!n`
} Z6Nj<2u2
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publicList findByNamedQuery(finalString ':\fl.b
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namedQuery){ o3n3URu\
return getHibernateTemplate #e.jY_
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().findByNamedQuery(namedQuery); 4l&"]9D
} |e*Gz D
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publicList findByNamedQuery(finalString query, z wL3,!t
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finalObject parameter){ T&r +G!2
return getHibernateTemplate 8F zHNG
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().findByNamedQuery(query, parameter); ,0!uem}1i
} 8zdT9y|Ig
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publicList findByNamedQuery(finalString query, mEoA#U
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finalObject[] parameters){ V:
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return getHibernateTemplate _QR
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().findByNamedQuery(query, parameters); F:%^&%\
} S|"Fgoj r
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publicList find(finalString query){ #gh
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return getHibernateTemplate().find * R%.a^R
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(query); x6LjcRS|
} cDCJ]iDs
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publicList find(finalString query, finalObject !#q{Z>H`
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parameter){ U,e'ZRU6
return getHibernateTemplate().find EMLx?JnP
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(query, parameter);
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} TWUUvj`.
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public PaginationSupport findPageByCriteria ITONpg[f
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(final DetachedCriteria detachedCriteria){ [*Q-nZ/L
return findPageByCriteria uJgI<l'|e3
[FGgkd}
(detachedCriteria, PaginationSupport.PAGESIZE, 0); &.zj5*J
} 5.wiTy
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public PaginationSupport findPageByCriteria j")FaIM
+ 3h`UF
(final DetachedCriteria detachedCriteria, finalint W6vf=I@f
<
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startIndex){ yO=p3PV d
return findPageByCriteria H)E^!eo
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(detachedCriteria, PaginationSupport.PAGESIZE, 7,*%[#-HE
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startIndex); j eq:
} [ByQ;s5tY
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public PaginationSupport findPageByCriteria UFe(4]^
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(final DetachedCriteria detachedCriteria, finalint B oqJ
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pageSize, /PXioiGcs
finalint startIndex){ ~].ggcl`w
return(PaginationSupport) 0 " y%9
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getHibernateTemplate().execute(new HibernateCallback(){ SauH>
publicObject doInHibernate /THnfy\
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(Session session)throws HibernateException { qaG# ;
Criteria criteria = ^O)ve^P
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detachedCriteria.getExecutableCriteria(session); $"\O;dp7l
int totalCount = g6%Z)5D]!
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((Integer) criteria.setProjection(Projections.rowCount WhFS2Jl0
Ly7!R$X
()).uniqueResult()).intValue(); _yv Luj
criteria.setProjection _9@ >;]
xx }GOY.J
(null); R*9NR,C
List items = /syVGmS'M
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criteria.setFirstResult(startIndex).setMaxResults 0/ !,Dn
26L~X[F
(pageSize).list(); *5OCqU+g
PaginationSupport ps = dlD ki.
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new PaginationSupport(items, totalCount, pageSize, 9S1)U$
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startIndex); -.iNNM&a
return ps; +th%enRB
} he$XLTmr:
}, true); r?A|d.Tl
} ?WpenUWk
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public List findAllByCriteria(final ,*Z.
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DetachedCriteria detachedCriteria){ A6{b?aQ
return(List) getHibernateTemplate E4i0i!<z
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().execute(new HibernateCallback(){ 1J}8sG2`
publicObject doInHibernate <
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(Session session)throws HibernateException { `t(D!
Criteria criteria = gSt`%
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detachedCriteria.getExecutableCriteria(session); 3yA2WW
return criteria.list(); oVOm_N
} z@Hp,|Vy[
}, true); Uxu\u0*
} hs+kr?Pg`
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public int getCountByCriteria(final O+~ 7l?o
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DetachedCriteria detachedCriteria){ ~9\zWRh
Integer count = (Integer) wJ+Aw
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getHibernateTemplate().execute(new HibernateCallback(){ 'h1b1,b~
publicObject doInHibernate o0It82?RN
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(Session session)throws HibernateException { ]J7Qgp)i
Criteria criteria = 1.U`D\7mb
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detachedCriteria.getExecutableCriteria(session); &M/>tEZ)
return %^]?5a!
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criteria.setProjection(Projections.rowCount
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()).uniqueResult(); @>Mxwpl?
} xiblPF_n3
}, true); ;gg\;i}^
return count.intValue(); V5f9]D
} MrRaU x6z
} 790-)\:CY
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用户在web层构造查询条件detachedCriteria,和可选的 m!tx(XsXU
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 8;14Q7,S
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PaginationSupport的实例ps。 .
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ps.getItems()得到已分页好的结果集 An*~-u9m
ps.getIndexes()得到分页索引的数组 M$4[)6Y
ps.getTotalCount()得到总结果数 F[
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ps.getStartIndex()当前分页索引 ]i<[d,
ps.getNextIndex()下一页索引 Cqii}
ps.getPreviousIndex()上一页索引 NEt1[2X%
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 F!zP<A"
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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 7>XDNI
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一下代码重构了。 "tjLc6Xl^
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我把原本我的做法也提供出来供大家讨论吧: WrPUd{QM
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首先,为了实现分页查询,我封装了一个Page类: H{J'#
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java代码: J^R=dT!
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/*Created on 2005-4-14*/ H~ZV*[A`
package org.flyware.util.page; qTZFPfyU
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/** T91moRv
* @author Joa Bqma\1cgb
* lL1k.&|5m
*/ .EM`.
publicclass Page { `Al;vVMRO
qC
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/** imply if the page has previous page */ D}8EER b
privateboolean hasPrePage; c'/l,k
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/** imply if the page has next page */ =UyLk-P
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privateboolean hasNextPage; 4pw6bK,s2\
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/** the number of every page */ MSf;ZB
privateint everyPage; Ft}@1w5
:y7c k/>
/** the total page number */ %|s+jeUDn|
privateint totalPage; |:8bNm5[
boDt`2=
/** the number of current page */ A}eOFu`
privateint currentPage; RX/hz|
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/** the begin index of the records by the current $D G?M6
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query */ ZP{*.]Qu
privateint beginIndex; \rv<$d@L
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/** The default constructor */ Ub6jxib
public Page(){ -GxaV #{
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} eM8}X[
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/** construct the page by everyPage 82l~G;.n3
* @param everyPage 1I:+MBGin
* */ 41&\mx
public Page(int everyPage){ KCs[/]
this.everyPage = everyPage; 4:FK;~wM&x
} I_]^ .o1q
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/** The whole constructor */ 50X([hIr
public Page(boolean hasPrePage, boolean hasNextPage, wb0L.'jyR)
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int everyPage, int totalPage, q.;u?,|E/
int currentPage, int beginIndex){ i{`:(F5*
this.hasPrePage = hasPrePage; vam;4vyu
this.hasNextPage = hasNextPage; u A<n
this.everyPage = everyPage; Hl,W=2N
this.totalPage = totalPage; ~sh`r{0
this.currentPage = currentPage; 2WdyxjQ
this.beginIndex = beginIndex; E 7{U|\
} ,y#Kv|R
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/** A6thXs2
* @return ln6d<;
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* Returns the beginIndex. 6^`1\
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*/ )P
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publicint getBeginIndex(){ -Ps!LI{@
return beginIndex; %#kg#@z_`e
} $|@
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/** ]Gsv0Xk1
* @param beginIndex ,
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* The beginIndex to set. bE !G JZ
*/ 7fZDsj:
publicvoid setBeginIndex(int beginIndex){ ``hf=`We
this.beginIndex = beginIndex; )
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} asppRL||
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/** pOIJH =#
* @return ,s"^kFl
* Returns the currentPage. s;ls qQk
*/ 0Qf,@^zL*
publicint getCurrentPage(){ Po^?QVJ7
return currentPage; yPb" V
} n-tgX?1'
AP 2_MV4W
/** *nkoPVpC
* @param currentPage -lY6|79bF
* The currentPage to set. |v3T!
*/ n{argI8wF
publicvoid setCurrentPage(int currentPage){ x??+~$}\*-
this.currentPage = currentPage; Rl?_^dPx
} c(xrP/yOwi
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/** L>Fa^jq5
* @return "#2a8#
* Returns the everyPage. #lL^?|M
*/ )q8p k2
publicint getEveryPage(){ =O5pY9UO
return everyPage; #A JDWelD
} a%JuC2
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/** -
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* @param everyPage Nk?
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* The everyPage to set. ?]_$Dcmx
*/ |\pj;XU
publicvoid setEveryPage(int everyPage){ KQ!8ks]
this.everyPage = everyPage; JcsHt;
} /~%&vpF-L
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/** }HYbS8 '
* @return "c%0P"u
* Returns the hasNextPage. |"8b_Cq{
*/ q 376m-+
publicboolean getHasNextPage(){ Tztu}t]N
return hasNextPage; c_$=-Khk
} ?jv/TBZX4
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/** !C':
* @param hasNextPage _7Ju
* The hasNextPage to set. *5C7d*'
*/ q$d>(vbq
publicvoid setHasNextPage(boolean hasNextPage){ EIP/V
this.hasNextPage = hasNextPage; ~D j8z+^
} U2#"p
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:
/** cKca;SNql1
* @return !Iy_UfW
* Returns the hasPrePage. t%0VJB,Q2
*/ i+ ?^8#
publicboolean getHasPrePage(){ 1hY{k{+o
return hasPrePage; @1roe
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} 5uGq%(24
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/** @Md/Q~>
* @param hasPrePage ,f%S'(>w
* The hasPrePage to set. e'NJnPO
*/ 8b&/k8i:
publicvoid setHasPrePage(boolean hasPrePage){ cA?W7D
this.hasPrePage = hasPrePage; e8a+2.!&\
} R`qFg/S
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/** ?(1y
* @return Returns the totalPage. 03X1d-
* 6Pl<'3&
*/ v0{i0%d,?
publicint getTotalPage(){ ,?%Zc$\LW
return totalPage; 9s
q
} *~e?TfG
L,/%f<wd
/** 7&)bJ@1U
* @param totalPage Rr]Hy^w
* The totalPage to set. P/eeC"
*/ e#8Q L
publicvoid setTotalPage(int totalPage){ &DX! f
this.totalPage = totalPage; lTgjq:mn
} xJ]\+ 50
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} PJ%C N(0
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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 I+!0 O
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个PageUtil,负责对Page对象进行构造: f}P3O3Yv&
java代码: ]h+j)J}[A
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/*Created on 2005-4-14*/ ^6V[=!& H
package org.flyware.util.page; [RhO$c$[\
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import org.apache.commons.logging.Log; ",; H`V
import org.apache.commons.logging.LogFactory; FvjPdN/L?R
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/** $%#!bV
* @author Joa }Zn}
* VU3upy<
*/ S2&4g/
publicclass PageUtil { 2fd{hJDq;5
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privatestaticfinal Log logger = LogFactory.getLog
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(PageUtil.class); igPX#$0XU
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/** z<?)Rq"
* Use the origin page to create a new page oUU1+F-
* @param page /h3RmUy
* @param totalRecords s.C_Zf~3
* @return 4|DWOQ':
*/ M .mfw#*
publicstatic Page createPage(Page page, int #@Jq~$N|
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totalRecords){ 4H&+dRI"
return createPage(page.getEveryPage(), yY q,*<G
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page.getCurrentPage(), totalRecords); VMWf>ZU
} $ddCTS^
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/** }pkzH'$HJ
* the basic page utils not including exception oCz/HQoBk
.?$gpM?i
handler Q*Pq{]0K
* @param everyPage /%^#8<=|U
* @param currentPage /j.9$H'y
* @param totalRecords jse&DQ
* @return page gg2(5FPP
*/ I; rGD^
publicstatic Page createPage(int everyPage, int jmZI7?<z
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currentPage, int totalRecords){ UkFC~17P
everyPage = getEveryPage(everyPage); ]D\D~!R
currentPage = getCurrentPage(currentPage); tKXIk9e
int beginIndex = getBeginIndex(everyPage, X"%gQ.1|{j
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currentPage); l.M0`Cn-%
int totalPage = getTotalPage(everyPage, qJ-/7-$ ^
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totalRecords); c7H^$_^ =
boolean hasNextPage = hasNextPage(currentPage, u=e{]Ax#}
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totalPage); 7b+6%fV
boolean hasPrePage = hasPrePage(currentPage); r5^eNg k
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returnnew Page(hasPrePage, hasNextPage, Tw<q,O
everyPage, totalPage, xskz)kk
currentPage, ]6j{@z?{
f
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beginIndex); <1TAw.
} -mh3DhJ,
#AY&BWS$
privatestaticint getEveryPage(int everyPage){ RxQ *
return everyPage == 0 ? 10 : everyPage; \Vk:93OH21
} %(Icz?
h{qgEIk&
privatestaticint getCurrentPage(int currentPage){ yB!dp;gM{
return currentPage == 0 ? 1 : currentPage; kq-) ^,{y
} 7d\QB(~
&7s.`
privatestaticint getBeginIndex(int everyPage, int nJ;.Td
^B^9KEjTz
currentPage){ F"mmLao
return(currentPage - 1) * everyPage; vP,n(reM
} Dha1/g1q
_yT Ed"$
privatestaticint getTotalPage(int everyPage, int ~.|_ RdN
Iu6
totalRecords){ ?q [T
int totalPage = 0; Gq P5Kx+=
\{D"
!e
if(totalRecords % everyPage == 0) [D1Up
totalPage = totalRecords / everyPage; 6S{l'!s'
else xyxy`qR A
totalPage = totalRecords / everyPage + 1 ; !'I8:v&D
}QmqoCAE~m
return totalPage; Pzem{y7Ir
} D6Wa.,r
+cRn%ioVi
privatestaticboolean hasPrePage(int currentPage){ ji="DYtL
return currentPage == 1 ? false : true; QsW/X0YBv
} D m9sL!
cH)";]k*-
privatestaticboolean hasNextPage(int currentPage, [-x7_=E#
(-co.
int totalPage){ 4&iCht
=
return currentPage == totalPage || totalPage == }GIt!PG
tl>7^hH
0 ? false : true; 4Po_-4
} S8gs-gL#Og
," ql5Q4
P'rb%W
} :zR!/5
6H|S;K+
Mb=" Te>|
A %-6`>
?@8[e9lLD
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。 %|4UsWZ
FgO)DQm
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 ch]29
B/C,.?Or
做法如下: 1YMh1+1
1. 编写一个通用的结果存储类Result,这个类包含一个Page对象 :@&/kyGH
rM"l@3hP
的信息,和一个结果集List: eDB ;cN
java代码: w*Ihk)
|cY`x(?yP
eQ}4;^;M-
/*Created on 2005-6-13*/ :Qq#Z
package com.adt.bo; rLT!To
^C%<l(b
import java.util.List; S[QrS7
i?;Kq~,
import org.flyware.util.page.Page; B?wq=DoG
.sA.C]f
/** |&jXp%4T
* @author Joa *$*ce|V5
*/ JN6B~ZNf
publicclass Result { CH/rp4NeSy
5(8@%6>ruj
private Page page; )CyS#j#=
GJUL$9
private List content; b>$S<td
3mni>*q7d
/** iR0y"Cii
* The default constructor ,2)6s\]/b
*/ +^<](z
public Result(){ }&3~|kP~O
super(); ,=N.FS
} -%dCw6aX+
07 $o;W@
/** d5l UGRg
* The constructor using fields (tQc
* w*MpX
U<
* @param page KG5>]_GH
* @param content =rK+eG#,
*/ FGQzoS
public Result(Page page, List content){ 3k?X-|O8AZ
this.page = page; D,ln)["xm
this.content = content; W}1
;Z(.*
} 6`-jPR
wvPk:1wD5
/** Ic4H# w
* @return Returns the content. ,v&(Y Od
*/ k$7Jj-+~
publicList getContent(){ o8vug$=Z
return content; b_):MQ1{
} 2Wb]4-
V470C@
/** T,tdL
N-
* @return Returns the page. "wHFN>5B
*/ eR" <33{
public Page getPage(){ H7j0K ~U0
return page; @ry_nKr9
} +d;bjo 2
.6'qoo_N
/** )>- =R5ZV
* @param content Tu 7QCr5*
* The content to set.
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*/ "w.3Q96r
public void setContent(List content){ bY0|N[g
this.content = content; YUIi;
} ;d9QAN&0}
!GGkdg*-*9
/** I.k
*GW
* @param page Z)aUt
Srf
* The page to set. <A'$%`6m
*/ #
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publicvoid setPage(Page page){ E+w<RNBmz
this.page = page; N*&1GT#9
} 8pgEix/M5o
} u-5{U-^_
{,~3.5u
q%?in+l
[1
9,&]z
.h4 \Y A
2. 编写业务逻辑接口,并实现它(UserManager, )TH@#1
5N&?KA-
UserManagerImpl) `^Em&6!!
java代码: Eg3q!J&Z
`lt"[K<
w=J3=T@TD
/*Created on 2005-7-15*/ ~O&:C{9=
package com.adt.service; =$Nq
V%
6I\G2/:
import net.sf.hibernate.HibernateException; nK%LRcAs
uGEfIy 2
import org.flyware.util.page.Page; ~1vDV>dpE
*itUWpNhr
import com.adt.bo.Result; h{HHLR
` v@m-j6
/** &@Be2!%'9K
* @author Joa @7j AL -
*/ (jl
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publicinterface UserManager { h|{]B,.Lh
JHTSUq
public Result listUser(Page page)throws Q| ?L*Pq2I
l3I:Q^x@
HibernateException; zsyIV!(
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} 6.nCV0xA
'F0e(He@,
+Kbjzh3<wG
p xa*'h"b^
XXn67sF/
java代码: ~;{;,8!)
S8j{V5R'
65$+{s
/*Created on 2005-7-15*/ Lhb35;\
package com.adt.service.impl; "N bq#w\
ieCEo|b
import java.util.List; ]{mPh\
qwgPk9l
import net.sf.hibernate.HibernateException; =QiI :|eRA
JL}_72gs
import org.flyware.util.page.Page; c>:wd@w
import org.flyware.util.page.PageUtil; 62o:,IcoG
EGU
0)<
import com.adt.bo.Result; tq6!`L }3
import com.adt.dao.UserDAO; 94.DHZqh
import com.adt.exception.ObjectNotFoundException; peuZ&yK+"
import com.adt.service.UserManager; ;d"F%M
y
9oR@UW1
/** CiLg]va
* @author Joa jrr*!^4|
*/ /,&<6c-Q@W
publicclass UserManagerImpl implements UserManager { ,I(d6
KD7dye
private UserDAO userDAO; J^5So
zC@o
/** `FDiX7M
* @param userDAO The userDAO to set. J1RJ*mo7,
*/ (G4at2YLd
publicvoid setUserDAO(UserDAO userDAO){ ^"1n4im
this.userDAO = userDAO; )SRefW.v
} MvHm)h
6/Xk7B
/* (non-Javadoc) l2rd9-T
* @see com.adt.service.UserManager#listUser {9;CNsd
lC("y'
::
(org.flyware.util.page.Page) ~>Fu5i $i
*/ a# y;dK
public Result listUser(Page page)throws 0gy/:T
n :\~'+$
HibernateException, ObjectNotFoundException { FR4QUk
int totalRecords = userDAO.getUserCount(); NAQAU
*yP
if(totalRecords == 0) *,8^@(th
throw new ObjectNotFoundException G"U9E5O
)c83/= <v
("userNotExist"); kmsb hYM)
page = PageUtil.createPage(page, totalRecords); q?oP?cCw
List users = userDAO.getUserByPage(page); NI}yVV
returnnew Result(page, users); [.'|_l
} QP^Cx=
bv9i*]
} "9P>a=Y
LX7FaW
|\<`Ib4j
[.8BTj1%
}=UHbU.n~!
其中,UserManagerImpl中调用userDAO的方法实现对User的分页查 fk[-mZ
o"Euwh!!
询,接下来编写UserDAO的代码: c~$)UND^
3. UserDAO 和 UserDAOImpl: fc%xS7&
java代码: *:YiimOY"
] =xE
WJndoB.f[2
/*Created on 2005-7-15*/ $L>@Ed<
package com.adt.dao; |`Ntv}
HU}7zK2
import java.util.List; 1N^[.=
-p&" y3<p
import org.flyware.util.page.Page; .hP D$o
a|x.C6Pe
import net.sf.hibernate.HibernateException; w d^':
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/** /W30~y
* @author Joa *@r/5pM2}
*/ ,I$`-$_'
publicinterface UserDAO extends BaseDAO { M~#g RAUJ
ygS;$2m%2
publicList getUserByName(String name)throws n Fg~< $d
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HibernateException; )!Z*.?
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publicint getUserCount()throws HibernateException; A*R^n}sh
VimE@ Hz
publicList getUserByPage(Page page)throws >,Ci?[pf
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bzs
HibernateException; "f2$w
r1m]HFN
} O67W&nz
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R)(T^V`{
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java代码: >`mVY=Hi
S_4?K)n #
#n#}s
/*Created on 2005-7-15*/ UiP"Ixg6
package com.adt.dao.impl; 4Zddw0|2
T|op$ s|
import java.util.List; T_
<@..C
PfD.:amN7
import org.flyware.util.page.Page; oUr66a/[U
v2\FA(BPn
import net.sf.hibernate.HibernateException; J T7nG.9
import net.sf.hibernate.Query; ")5":V~fN
r:'.nhe
import com.adt.dao.UserDAO; {n.PF8A5X
Z'W=\rl
/** )5JFfp)#
* @author Joa vjCu4+w($Z
*/ M,,bf[p$
public class UserDAOImpl extends BaseDAOHibernateImpl Xp% v.M
tBWrL{xLe
implements UserDAO { mzKiO_g}
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/* (non-Javadoc) JPUW6e07o
* @see com.adt.dao.UserDAO#getUserByName D&
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nYSiS}?S.
(java.lang.String) W:nef<WH
*/ .bg~>T+<
publicList getUserByName(String name)throws l0m-$/
eA ?RK.e
HibernateException { QXFo1m
String querySentence = "FROM user in class :#ik. D
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com.adt.po.User WHERE user.name=:name"; P=Jo+4O
Query query = getSession().createQuery 'ya{9EdlT
9YyLf ;
(querySentence); 7"x;~X
query.setParameter("name", name); [ /b2=>
return query.list(); %E>Aw>]v
} ]^7@}Ce_
[kB7@o
/* (non-Javadoc) 9T9!kb
* @see com.adt.dao.UserDAO#getUserCount() Lv7(st%`
*/ =v&hWjP
publicint getUserCount()throws HibernateException { i$#;Kpb`^
int count = 0; =BAr .m+"
String querySentence = "SELECT count(*) FROM KYI/
*n
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user in class com.adt.po.User"; P4'Q/Sj
Query query = getSession().createQuery &`r-.&Y
#q$HQ&k
(querySentence); `UaD6Mc<Mz
count = ((Integer)query.iterate().next /-'}q=M
^
VyKd
()).intValue(); 7Q9 w?y~c
return count; NwvC[4
} ?e4YGOe.
{\1?ZrCI&
/* (non-Javadoc) k]|~>9eY]
* @see com.adt.dao.UserDAO#getUserByPage yx[/|nZDC4
gZXi]m&
(org.flyware.util.page.Page) lrE5^;/s1
*/ ET*SB
publicList getUserByPage(Page page)throws }R2u@%n{
pah'>dAL
HibernateException { G e@{_
String querySentence = "FROM user in class SKN`2[ahD
Ic<2QknmP
com.adt.po.User"; VCkq"f7cw
Query query = getSession().createQuery u&vf+6=9Dd
YkSl^j[DHs
(querySentence);
jB2[(
query.setFirstResult(page.getBeginIndex()) ,ZNq,$j
.setMaxResults(page.getEveryPage()); (5YM?QAd
return query.list(); ^{`exCwMx
}
b8t7u
C{rcs'
} M|h3Wt~7
$h"\N$iSq
Wn2NMXK
V}CG:9;
U7F!Z(
9
至此,一个完整的分页程序完成。前台的只需要调用 /,yd+wcW#
\}b%E'+_T
userManager.listUser(page)即可得到一个Page对象和结果集对象 bAqA1y3=
7JH6A'&
的综合体,而传入的参数page对象则可以由前台传入,如果用
qEOhwrh
\M^bD4';>
webwork,甚至可以直接在配置文件中指定。 M%m4i9~!?
f$$ /H>MJ
下面给出一个webwork调用示例: {!L~@r
java代码: Q)h(nbbVak
#;yZ
r#a=@
/*Created on 2005-6-17*/ x 9fip-
package com.adt.action.user; a;+9mDXx:
O^
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import java.util.List; CA~-rv
,f>k%_U}
import org.apache.commons.logging.Log; _Fl9>C"u
import org.apache.commons.logging.LogFactory; Svmy(w~m
import org.flyware.util.page.Page; $U~]=.n
0GeTSFj
import com.adt.bo.Result; 3]S$ih&A
import com.adt.service.UserService; )y$(AJx$
import com.opensymphony.xwork.Action; ;.980+i1
~c `l@:
/** sO@Tf\d
* @author Joa `|q(h Ow2
*/ YOO+R{4(
publicclass ListUser implementsAction{ {`@G+JV~Jw
\4fQMG
privatestaticfinal Log logger = LogFactory.getLog [4f{w%~^
=aW9L)8D
(ListUser.class); L!xi
_t^&Ah*
private UserService userService; ?Ir:g=RP*
k<?b(&`J
private Page page; P&Vv/D
6'f;-2
privateList users; FYQS)s
vFmZ<C'
)
/* tCt#%7J;a
* (non-Javadoc) abVmkdP_s
* ?:0Jav
* @see com.opensymphony.xwork.Action#execute() 8quaXVj^a
*/ |FRg\#kf%
publicString execute()throwsException{ 8}:nGK|kx
Result result = userService.listUser(page); -QNh
page = result.getPage(); ]`WJOx4
users = result.getContent(); z
F;K
return SUCCESS; pA4xbr 2
} 4*;MJ[|
>vsqG=x
/** m1A J{cs
* @return Returns the page. f|gg
*/ \9EjClfo
public Page getPage(){ J'r^/
return page; |R:'\+E
} qH_Dc=~la
>9J:Uo1z
/** bg0Wnl
* @return Returns the users. C7AUsYM
*/ 9gZ$
publicList getUsers(){ &cTU
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return users; +"VP-s0
} BDVtSs<7
/Ci<xmP
/** i}?>g -(
* @param page !|>"o7
* The page to set. U/BR*Zn]*
*/ e>7i_4(C
publicvoid setPage(Page page){ &kw@,];4Z
this.page = page; T[A69O]v
} WX0tgXl
xId.GWY1
/** E4xa[iZ
* @param users p()xz
* The users to set. v.5+7,4
*/ <0?W{3NqI
publicvoid setUsers(List users){ SX-iAS[<
this.users = users; ;*&-C9b
} ;9g2?-svw
RpYERAgT
/** 6LZ;T.0o
* @param userService $,'*f?d
* The userService to set. dcT80sOC
*/ !{41!O,K#
publicvoid setUserService(UserService userService){ _wL BA^d^
this.userService = userService; c[Zje7 @
} 2f_:v6
} dC4'{n|7
01o4Th m
tklH@'q
WOf 4o
L&OwPd
上面的代码似乎看不出什么地方设置了page的相关初值,事实上, 5NLDYi@3
;6hOx(>`=
可以通过配置文件来进行配置,例如,我想每页显示10条记录,那 CVR3
A'
!5?<% *
么只需要: o%*xvH*A
java代码: c6/=Gq{.
P
L+sR3bR
B,fo(kG
<?xml version="1.0"?> /|#fejPh
<!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork S#[j )U-
e(8Ba X_
1.0//EN" "http://www.opensymphony.com/xwork/xwork- -s'-eQF J
vSLtFMq^(
1.0.dtd"> !$>R j
9JKEw
<xwork> EAby?51+
cPc</[x[W
<package name="user" extends="webwork- B48={
~.lPEA %%
interceptors"> h3@v+Z<}
!FF U=f
<!-- The default interceptor stack name B^jc3 VsR
@gXx1hEg
--> XHGFf_kW_N
<default-interceptor-ref 5.J.RE"M
`x%>8/
name="myDefaultWebStack"/> 63x?MY6
u,Kly<0j
<action name="listUser" Ok\7y-w^
1 I",L&S1
class="com.adt.action.user.ListUser"> T37XBg H
<param VTHH&$ZNq
}f7j8py
name="page.everyPage">10</param> 2jCf T>`3
<result 2SR: FUV/
I[X772K
name="success">/user/user_list.jsp</result> r0 uwPf
</action> Tc3yS(aq
=[jXe
</package> 0NX,QD
4#hSJ(~7S
</xwork> @>H75
t}tEvh
!brf(-sr)
uOdl*| T?
"|KP'<8%
G[q$QB+
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
kX2rp?{
fw{gx
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。 Z0r?|G0
nwCrZW
注:上面的<param>的配置,还需要webwork和Spring整合的配合。 %sQ^.` 2
"kgdbAZ
ZO c)
I`4*+a'q&
K0Fh%Y4)QH
我写的一个用于分页的类,用了泛型了,hoho e'b(gD}
~zNAbaC+>t
java代码: _n>,!vH
fkNbS
Q^txVUL
package com.intokr.util; "C0Q(dr/n
]f9Cx\d:k
import java.util.List; w}cPs{Vi"
Czu\RXJR
/** m5Di=8
* 用于分页的类<br> Pw!MS5=r
* 可以用于传递查询的结果也可以用于传送查询的参数<br> i5,kd~%O
* xAMW-eF?d
* @version 0.01 <
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* @author cheng O55 xS+3^k
*/ 9o:Lz5o
public class Paginator<E> { 03S]8l
privateint count = 0; // 总记录数 161xAig
privateint p = 1; // 页编号 !^Y(^RS@
privateint num = 20; // 每页的记录数 Whf.fK
privateList<E> results = null; // 结果 ysf~|r4s
?zHPJLv|Y
/** j
Dv{/)
* 结果总数 zi*R`;_`,
*/ :$BCRQ
publicint getCount(){ *>qp:;,DKP
return count; #d2.\X}A"3
} ly3\e_z:G
Bad:no\W
publicvoid setCount(int count){ ,0HRAmG
this.count = count; s
15oN
} )*x6 FfTUd
e|WJQd4+S
/** GKc`xIQ
* 本结果所在的页码,从1开始 rK]Cr9W M
* R>mmoG}MQ[
* @return Returns the pageNo. q\p:X"j|
*/ :\7X}n*&
publicint getP(){ eu|;eP-+d
return p; xCl1g4N
} .rqhi
?[Q3q4
/** DG ;_Vg
* if(p<=0) p=1 #O}
,`[<
* iaE^a^*
* @param p TXvI4"&
*/ YRN06*hS
publicvoid setP(int p){ s %\-E9
T
if(p <= 0) ^mO~W!"
p = 1; fbKkq.w
this.p = p; S<@7_I
} D}8[bWF
^pF&`2eD
/** mtmjZP(w
* 每页记录数量 !1 8clL
*/ `q*M4,
publicint getNum(){ EZ$>.iy{
return num; ={d>iB yq
} aYS!xh206
EL 8<U
/** OJ5#4qJ[
* if(num<1) num=1 Q&=w_Wc
*/ Mh/dpb\Z
publicvoid setNum(int num){ cacr=iX
if(num < 1) X4Ic;
num = 1; yiC^aY=-
this.num = num; VZymM<