Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 S9%,{y
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 x_C0=Q|K3
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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 tL<.B
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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 '^$+G0jv
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分页支持类: M#m;jJqON
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java代码: x#R6Ez7
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package com.javaeye.common.util; :rjfAe=s
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import java.util.List; (vchZn#
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publicclass PaginationSupport { _jgtZ
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publicfinalstaticint PAGESIZE = 30; FC+h
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privateint pageSize = PAGESIZE; HSAr6h
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privateList items; @>V;guJC%
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privateint totalCount; <c!gg7@pm
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privateint[] indexes = newint[0]; N>]J$[j
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privateint startIndex = 0; qc\D=3#Yp
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public PaginationSupport(List items, int BHZhdm@),
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totalCount){ 7\R"RH-
setPageSize(PAGESIZE); W-/V5=?
setTotalCount(totalCount); Qf}.= (
setItems(items); RgQs`aI
setStartIndex(0); =6Gn?
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} :Q@/F;Z?
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public PaginationSupport(List items, int mw;4/
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totalCount, int startIndex){ vZ.<OD4
setPageSize(PAGESIZE); j0a=v}j3
setTotalCount(totalCount); 9n;6zVV%`
setItems(items); /@\R
setStartIndex(startIndex);
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} ?2dI8bG
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public PaginationSupport(List items, int u#Jr_ze
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totalCount, int pageSize, int startIndex){ K5BL4N
setPageSize(pageSize); kV4Oq.E
setTotalCount(totalCount); +`g&hO\W
setItems(items); nhjT2Sl
setStartIndex(startIndex); P R3Arfle
} *L$_80
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publicList getItems(){ [0]A-#J
return items; *pv<ZF0>
} ~QxW^DGa7]
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publicvoid setItems(List items){ c1jRj=\
this.items = items; Yv@n$W`:
} 3,6f}:CG
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publicint getPageSize(){ Y68A+
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return pageSize; "`4ky]
} 4"(rZWv
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publicvoid setPageSize(int pageSize){ -eyF9++`
this.pageSize = pageSize; 3]mprX'
} W0~G`A(:;
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publicint getTotalCount(){ 8B?U\cfa^
return totalCount; s hH2/.>
} /(51\RYkir
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publicvoid setTotalCount(int totalCount){ xUsL{24
if(totalCount > 0){ ?{^_z_,
this.totalCount = totalCount; AguE)I&m
int count = totalCount / 1(IZ,*i
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pageSize; ob;|%_
if(totalCount % pageSize > 0) xn503,5G*7
count++; 8{2
indexes = newint[count]; ;..z)OP_
for(int i = 0; i < count; i++){ @=dv[P"jn
indexes = pageSize * nM2<u[{gF
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} #5)/B
}else{ _r{H)}9
this.totalCount = 0; f?)7MR=
} qfE0J;e
} $$1t4=Pz
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publicint[] getIndexes(){ ge
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return indexes; 'A7!@hVy
} j0; ~2W#G*
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publicvoid setIndexes(int[] indexes){ :! oJmvy
this.indexes = indexes; bkDVW
} HC6U_d1-6
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publicint getStartIndex(){ 3U{
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return startIndex; X_o#!
} e,e(t7c?d
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publicvoid setStartIndex(int startIndex){ .k]`z>uv
if(totalCount <= 0) <lf692.3
this.startIndex = 0; D0FX"BY7
elseif(startIndex >= totalCount) .s*N1
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this.startIndex = indexes W4^zKnH
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[indexes.length - 1]; & mO n]
elseif(startIndex < 0) (6ga*5<
this.startIndex = 0; 5+M,X kg
else{ 9,INyEyAL
this.startIndex = indexes CsA (oX
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[startIndex / pageSize]; ))|d~m
} >^jBE''
} T(?w}i
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publicint getNextIndex(){ ?uSoJM`wa!
int nextIndex = getStartIndex() + {wz)^A
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pageSize; hi!A9T3%}M
if(nextIndex >= totalCount) FE!jN-#
return getStartIndex(); +Pl)E5W!=`
else V
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return nextIndex; w<`0D)mQ
} 6T$=(I <4
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publicint getPreviousIndex(){ i#*[,
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int previousIndex = getStartIndex() - 6v3l^~kc'
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pageSize; +s}&'V^
if(previousIndex < 0) l|WFS
return0; (uvQ/!
else ;Yee0O!d4
return previousIndex; hE {";/}J
} u?`{s88_mF
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} ^\ x'4!W
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抽象业务类 jlj ge=#c2
java代码: dzOco)y
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/** 61H_o7XXk
* Created on 2005-7-12 nm1dd{U6^
*/ /*y5W-'d^
package com.javaeye.common.business; ?-)!dl%N
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import java.io.Serializable; (Y)2[j
import java.util.List; T<0 r,
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import org.hibernate.Criteria; (U&
import org.hibernate.HibernateException; (-WRZLOQ
import org.hibernate.Session; pZ>yBY?R8>
import org.hibernate.criterion.DetachedCriteria; z+yq%O
import org.hibernate.criterion.Projections; q|<B9Jk
import a|z-EKV
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org.springframework.orm.hibernate3.HibernateCallback; <9,h!
import Bn]=T
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org.springframework.orm.hibernate3.support.HibernateDaoS J|
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upport; o`c+eMwr(
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import com.javaeye.common.util.PaginationSupport; Fy{yg]O"
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public abstract class AbstractManager extends JhFn"(O
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HibernateDaoSupport { j_2g*lQ7a
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privateboolean cacheQueries = false; h]s6)tII
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privateString queryCacheRegion; AT1cN1:4?
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publicvoid setCacheQueries(boolean p*c(dkOe8
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cacheQueries){ 8S#$'2sT
this.cacheQueries = cacheQueries; O z0-cM8t
} Vbv^@Kp
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publicvoid setQueryCacheRegion(String w317]-n
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queryCacheRegion){ &b#d4p6&l
this.queryCacheRegion = Nx.9)MjI
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queryCacheRegion; jz<}9Kze
} tAN!LI+w
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publicvoid save(finalObject entity){ #`3Q4
getHibernateTemplate().save(entity); ZFtR#r(~41
} @HbRfD/!
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publicvoid persist(finalObject entity){ y7UU'k`
getHibernateTemplate().save(entity); _\d|`3RM
} ^)9/Wz _x
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publicvoid update(finalObject entity){ nqH[
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getHibernateTemplate().update(entity); Oz%6y
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} bWA_a]G
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publicvoid delete(finalObject entity){ d\#yWY
getHibernateTemplate().delete(entity); Nmx\qJUR(
} m~Pk]~j
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publicObject load(finalClass entity, 'df@4} 9
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finalSerializable id){ 9mHCms
return getHibernateTemplate().load Mi.2
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(entity, id); P\Qvj7_
} S=P}Jpq?Y;
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publicObject get(finalClass entity, \9,lMK[b
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finalSerializable id){ |[n\'Xy;{
return getHibernateTemplate().get (KC08
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(entity, id); !7\dr )
} &]a(5
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publicList findAll(finalClass entity){ |rJN
return getHibernateTemplate().find("from X$==J St
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" + entity.getName()); Po=:-Of:
} x(u.(:V
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publicList findByNamedQuery(finalString (zsmJe
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namedQuery){ =?Ry,^=b
return getHibernateTemplate LiHJm-
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().findByNamedQuery(namedQuery); W\B@0Is o
} 'exR;q\
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publicList findByNamedQuery(finalString query, dKPXs-5
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finalObject parameter){ ]z7pa^
return getHibernateTemplate t@lTA>;U@
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().findByNamedQuery(query, parameter); n. N0Nhd
} GKg #nXS
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publicList findByNamedQuery(finalString query, A\ mSS
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finalObject[] parameters){ L7 FFa:#
return getHibernateTemplate te;bn4~
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().findByNamedQuery(query, parameters); i|H^&$|
} <AVWT+,
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publicList find(finalString query){ _Hq)@AI
return getHibernateTemplate().find 9_*3xu<7i
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(query); BpFXe7
} s#8}&2#l
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publicList find(finalString query, finalObject 3NwdE/x\
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parameter){ U>n.+/ss
return getHibernateTemplate().find "OP$n-*@%
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(query, parameter); y\6C9%.
} V:D?i#%,z
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public PaginationSupport findPageByCriteria V+'zuX
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(final DetachedCriteria detachedCriteria){ A{{rNbCK
return findPageByCriteria B_c-@kl
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); =;8q`
} 4[r:DM|8
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public PaginationSupport findPageByCriteria s?sr0HZ
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(final DetachedCriteria detachedCriteria, finalint ?6[u\V
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startIndex){ l>Zp#+I-
return findPageByCriteria PVq y\i
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(detachedCriteria, PaginationSupport.PAGESIZE, W}^>lM\8
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startIndex); <UwA5X`0e.
} "8[Vb#=*e
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public PaginationSupport findPageByCriteria tdi}P/x
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(final DetachedCriteria detachedCriteria, finalint <~5$<L4
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pageSize, 6~Zq
finalint startIndex){ A@EUH
return(PaginationSupport) g;nPF*(
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getHibernateTemplate().execute(new HibernateCallback(){ 4y9n,~Qgw
publicObject doInHibernate X%M*d%n b
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(Session session)throws HibernateException { (@*#Pn|A
Criteria criteria = ~o/e0
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detachedCriteria.getExecutableCriteria(session); x6~`{N1N
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int totalCount = ""F'Nzy
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((Integer) criteria.setProjection(Projections.rowCount /I'
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()).uniqueResult()).intValue(); 6n.C!,Zmn
criteria.setProjection JMYM}G
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(null); R$40cW3`
List items = Qte'f+
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criteria.setFirstResult(startIndex).setMaxResults @7B!(Q
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(pageSize).list(); 8:0.Pi(ln@
PaginationSupport ps = @k2nID^>
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new PaginationSupport(items, totalCount, pageSize, E2{SKIUm
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startIndex); w6l8RNRe
return ps; e?~6HP^%.
} KGb3n;]
}, true); {oN7I'>
} cw{[% 7
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public List findAllByCriteria(final 0/JusQ
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DetachedCriteria detachedCriteria){ e|ngnkf(G
return(List) getHibernateTemplate h"G#} C]
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().execute(new HibernateCallback(){ hK&/A+*
publicObject doInHibernate /A;!g5Y
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(Session session)throws HibernateException { @{!c [{x,T
Criteria criteria = Mrlv(1PQT
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detachedCriteria.getExecutableCriteria(session); bO%bMZWB!y
return criteria.list(); @9^ozgg
} A/EW57v"
}, true); HW(cA}$
} |};P"&
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public int getCountByCriteria(final C.
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DetachedCriteria detachedCriteria){ g2v0!
Integer count = (Integer) -&*
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getHibernateTemplate().execute(new HibernateCallback(){ &i,xod6$
publicObject doInHibernate ;V~[kF=t0
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(Session session)throws HibernateException { E1'HdOh&z
Criteria criteria = WBgS9qiB
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detachedCriteria.getExecutableCriteria(session); I|*w?i*
return cf#2Wg)
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criteria.setProjection(Projections.rowCount i5sNCt
) )q4Rh
()).uniqueResult(); I]|X6
} Gvk)H$ni
}, true); %(IkUD
return count.intValue(); >M\3tB2C
} fWKI~/eUY|
} >i %{5d
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用户在web层构造查询条件detachedCriteria,和可选的 [;`B
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 5J^S-K^r
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PaginationSupport的实例ps。 Z6eM~$Y
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ps.getItems()得到已分页好的结果集 5G"DgG*<
ps.getIndexes()得到分页索引的数组 S:IhJQ4K
ps.getTotalCount()得到总结果数 iYi3x_A`
ps.getStartIndex()当前分页索引 -\OvOkr
ps.getNextIndex()下一页索引 8X,dVX5LT
ps.getPreviousIndex()上一页索引 LD]a!eY
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 ]W^F!p~eC
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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 z ;>xI~
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一下代码重构了。 9Z.Xo kg
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我把原本我的做法也提供出来供大家讨论吧: TPjElBh
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首先,为了实现分页查询,我封装了一个Page类: Y.XNA]|
java代码: TR;" &'#k
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/*Created on 2005-4-14*/ >|{n";n&
package org.flyware.util.page; Ass :
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/** RLy(Wz3%
* @author Joa z TYHwx
* aQjs5RbP~
*/ }q<p;4<\F
publicclass Page { GM_~2Er]
" Y%fk/v8
/** imply if the page has previous page */ hkS0 ae
privateboolean hasPrePage; oeV.K.
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/** imply if the page has next page */ lZ5LHUzP
privateboolean hasNextPage; 6T"4<w[
Z^tTR]u\$
/** the number of every page */ WP5cC@x
privateint everyPage; WC&V9Yk
Q]/ZVcoqo
/** the total page number */ w)C/EHF
privateint totalPage; ~Up5 +7k@
{5 V@O_*{
/** the number of current page */ (G1KMy
privateint currentPage; eILdq*
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/** the begin index of the records by the current vIq>QXb;d
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query */
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privateint beginIndex; ~F [V
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/** The default constructor */ v2Ft=_*G|
public Page(){ WiU-syNh
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} |WkWZZ^
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/** construct the page by everyPage .-Z=Aa>
* @param everyPage nYsB^Nr6
* */ uSsP'qd
public Page(int everyPage){ v[Mh[CyB
this.everyPage = everyPage; ltWEA
} j.]ln}b/'+
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/** The whole constructor */ &0b\E73
public Page(boolean hasPrePage, boolean hasNextPage, m| uVmg!*
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int everyPage, int totalPage, /wi*OZ7R
int currentPage, int beginIndex){ dz6&TdEl
this.hasPrePage = hasPrePage; tf3R
this.hasNextPage = hasNextPage; i,h)VCc
this.everyPage = everyPage; BT^Im=A
this.totalPage = totalPage; .DR*MQI9
this.currentPage = currentPage; i}L*PCP
this.beginIndex = beginIndex; !U7}?i&H
} <B
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/** t5aX9WIW
* @return ~hxW3e
* Returns the beginIndex. &W8fEQwa
*/ xeB-fy)5+
publicint getBeginIndex(){ h.pVIO`
return beginIndex; 1rIL[(r4
} swz)gh-*
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/** }~v&
* @param beginIndex no$X0ia
* The beginIndex to set. z8dBfA<z
*/ D!DL6l`
publicvoid setBeginIndex(int beginIndex){ XZ=%XB:?
this.beginIndex = beginIndex; #e[S+a
} bXz*g`=;
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/** HPY;UN
* @return Bun^EJ)
* Returns the currentPage.
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*/ ,`ba?O?*G
publicint getCurrentPage(){ sis1Dh9:
return currentPage; #z61I"kU
} (sW$2a
Nh01NY;
/** % kaV?j
* @param currentPage ,`8:@<e
* The currentPage to set. {t*CSI
*/ A6I^`0/
publicvoid setCurrentPage(int currentPage){ G b4p"3
this.currentPage = currentPage; 'Yaq; mDY
} x21XzGLY|}
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/** -;O"Y?ME
* @return \bies1TBB^
* Returns the everyPage. w!b;.l
*/ #bS}?fj
publicint getEveryPage(){ R_=fH\c;
return everyPage; OD~yIV
} CHVAs9mrNB
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/** UJuz
* @param everyPage iX6*OEl/Q
* The everyPage to set. sVH
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*/ VFK]{!C_
publicvoid setEveryPage(int everyPage){ zCS&