Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 ,O~2
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 [S4\fy0
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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$9[|x
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自于Quake Wang的javaeye-core包的相应类,然后又做了很多修改 '6 'XBL?
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分页支持类: =hs@W)-O
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java代码: %|,<\~P
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package com.javaeye.common.util; 654%X(:q
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import java.util.List; 8_,ZJ9l;
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publicclass PaginationSupport { cY"^3Ot%^
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publicfinalstaticint PAGESIZE = 30; rODKM-7+
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privateint pageSize = PAGESIZE; V0AX1?H~ w
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privateList items; I coL/7k3
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privateint totalCount; ".0W8=
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privateint[] indexes = newint[0];
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privateint startIndex = 0; 0\#Q;Z2
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public PaginationSupport(List items, int l =yHx\
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totalCount){ _Nn!SE
setPageSize(PAGESIZE); Xdq,
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setTotalCount(totalCount); ;9PM?Iy[
setItems(items); kUUq9me&o
setStartIndex(0); uJOW%|ZN`
} Ax0,7,8y
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public PaginationSupport(List items, int jyGVb no`
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totalCount, int startIndex){ ffM(il/2
setPageSize(PAGESIZE); eC$v0Gtq
setTotalCount(totalCount); K*Jtyy}r
setItems(items); OVyy}1Hx
setStartIndex(startIndex);
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} @;6}xO2
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public PaginationSupport(List items, int %jxuH+L
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totalCount, int pageSize, int startIndex){ JC"K{V{
setPageSize(pageSize); Y*k<NeDyn
setTotalCount(totalCount); XX-T",
setItems(items); \vsrBM
setStartIndex(startIndex); 4c=kT@=jX
} AE&n^vdQW
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publicList getItems(){ y^=oYL
return items; pYVy(]1I(3
} HzV+g/8>A
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publicvoid setItems(List items){ cf'}*$[S
this.items = items; %h"<
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} l _O~v?
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publicint getPageSize(){ l :Nxl
return pageSize; 4p8jV*:@{
} ;CMC`h9,
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publicvoid setPageSize(int pageSize){ K=x1mM+RK
this.pageSize = pageSize; ,R}KcZG)
} oRThJ B
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publicint getTotalCount(){ s| r7DdI
return totalCount; %`T5a<
} \a2oM$PX
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publicvoid setTotalCount(int totalCount){ jL+}F /~r
if(totalCount > 0){ K4/P(*r`
this.totalCount = totalCount; ~|{)h^]@
int count = totalCount / P .4b+9Tx
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pageSize; UUf1T@-
if(totalCount % pageSize > 0) sQAc"S
count++; V1nZ M
indexes = newint[count]; (vsk^3R[6
for(int i = 0; i < count; i++){ kqigFcz!Y
indexes = pageSize * }t
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} :.[5('
}else{ N"1x]1'
this.totalCount = 0; 3b)T}g
} zg Y*|{4Sl
} /W$y"!^)J1
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publicint[] getIndexes(){ ~q?"w:@;x
return indexes; 4a.e
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} *CY6
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publicvoid setIndexes(int[] indexes){ o*wC{VP_
this.indexes = indexes; }Q r0T
} @z$pPo0fW
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publicint getStartIndex(){ D*T$ v
return startIndex; 'x,GI\;?
} BRU9LS
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publicvoid setStartIndex(int startIndex){ t:"=]zUU
if(totalCount <= 0) w
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this.startIndex = 0; @t;O"q'|
elseif(startIndex >= totalCount) ;TV'PJ
this.startIndex = indexes me[J\MJ;w^
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[indexes.length - 1]; w] 5U
elseif(startIndex < 0) mam5G!$
this.startIndex = 0; 7Ysy\gZ&wp
else{ X\p`pw$
this.startIndex = indexes uWR,6\_jY
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[startIndex / pageSize]; 0bPJEEd
} }lC64;yo
} 01-\:[{
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publicint getNextIndex(){ !|Xl 8lV`
int nextIndex = getStartIndex() + ?`T6CRZhr
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pageSize; =Y]'5cn{
if(nextIndex >= totalCount) 59Tg"3xB<
return getStartIndex(); xu"94y+
else 1fO2)$Y
return nextIndex; 36^C0uNdX
} 0+n&BkS'
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publicint getPreviousIndex(){ ?HEtrX,q
int previousIndex = getStartIndex() - STXqq[+Rf
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pageSize; 8tT&BmT
if(previousIndex < 0) G%j/eTTf
return0; _Qm7x>NT4
else 7}#*3*]
return previousIndex; I!F}`d
} e}](6"t`5
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} {m_A1D/_
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抽象业务类 M9(ez7Z
java代码: dJ%wVY0z=
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/** BGlGpl
* Created on 2005-7-12 zqekkR]
*/ ;Ch+X$m9
package com.javaeye.common.business; >+Sv9S
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import java.io.Serializable; HO%E-5b9
import java.util.List; G|QUujl
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import org.hibernate.Criteria; xecieC
import org.hibernate.HibernateException; !F0rd9
import org.hibernate.Session; *}
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import org.hibernate.criterion.DetachedCriteria; 7gVh!rm
import org.hibernate.criterion.Projections; 45Nv_4s
import MO));M)
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org.springframework.orm.hibernate3.HibernateCallback; ,h%D4EVx
import m%e^&N#%6r
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org.springframework.orm.hibernate3.support.HibernateDaoS Hk<X
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upport; ONjC(7
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import com.javaeye.common.util.PaginationSupport; I!|y;mh:it
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public abstract class AbstractManager extends M(n<Iu4^_
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HibernateDaoSupport { \]Y\P~n
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privateboolean cacheQueries = false; MxM](ew~7
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privateString queryCacheRegion; QRsqPh&-
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publicvoid setCacheQueries(boolean 4mEzcwo'
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cacheQueries){ Si#"Wn?|
this.cacheQueries = cacheQueries; R(M}0JRm
} ??|d=4g\
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publicvoid setQueryCacheRegion(String @PYW|*VS
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queryCacheRegion){ Jy]FrSm^
this.queryCacheRegion = 6?53q e
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queryCacheRegion; (3e;"'k
} ?wGiog<Q{
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publicvoid save(finalObject entity){ >nc4v6s
getHibernateTemplate().save(entity); gb.f%rlZ`
} Bj;\mUsk
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publicvoid persist(finalObject entity){ t{+M|Y
getHibernateTemplate().save(entity); p@#]mVJ>9
} ]b}B~jD
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publicvoid update(finalObject entity){ TcR=GR*cJ
getHibernateTemplate().update(entity); dVvZu% DFp
} o^6jyb!j
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publicvoid delete(finalObject entity){ [_j6cj]
getHibernateTemplate().delete(entity); (F/HU"C
} gdOe)il\
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publicObject load(finalClass entity, 7raSf&{&6b
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finalSerializable id){ @/9>=#4c
return getHibernateTemplate().load 6hp{,8|D"m
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(entity, id); h8em\<;
} I4rV5;f
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publicObject get(finalClass entity, q5%2WM]6
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finalSerializable id){ D)y{{g*Lnm
return getHibernateTemplate().get +e U`H[iu
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(entity, id); K*[9j 0
} l(gJLjTH%
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publicList findAll(finalClass entity){ t
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return getHibernateTemplate().find("from S)+CTVVE
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" + entity.getName()); :]yg
} =PV/`I_h
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publicList findByNamedQuery(finalString 2@sr:,\1
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namedQuery){ 10?qjjb&
return getHibernateTemplate #^Ys{
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().findByNamedQuery(namedQuery); UkZ\cc}aC/
} h!v/s=8c
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publicList findByNamedQuery(finalString query, 0D<TF>M;pn
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finalObject parameter){ _r]nJEF5
return getHibernateTemplate W+.{4K
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().findByNamedQuery(query, parameter); 7(NXCAO81
} #\LZ;&T'N
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publicList findByNamedQuery(finalString query, <FQFv
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finalObject[] parameters){ _|X7
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return getHibernateTemplate 4#_$@ r
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().findByNamedQuery(query, parameters); ocwE_dR{
} f|#8qiUS
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publicList find(finalString query){ +TF8WZZF.d
return getHibernateTemplate().find MQJ%He"
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(query); S7CV
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} R]Ek}1~?
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publicList find(finalString query, finalObject nkRK+~>
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parameter){ N
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return getHibernateTemplate().find Ig9d#c
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(query, parameter); ZE
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} 2d 8=h6
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public PaginationSupport findPageByCriteria DvYwCgLR
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(final DetachedCriteria detachedCriteria){ =Dk7RKoHF
return findPageByCriteria # $~ oe"
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); /zT`Y=1
} n P1GW6Pu
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public PaginationSupport findPageByCriteria .YR8v1Cp
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(final DetachedCriteria detachedCriteria, finalint 2+:'0Krc
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startIndex){ =X@o@1
return findPageByCriteria 7$7n71o
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(detachedCriteria, PaginationSupport.PAGESIZE, ^A!$i$NON
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startIndex); O%g\B8;
} .S7:;%qL6
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public PaginationSupport findPageByCriteria <lj\#'G3
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(final DetachedCriteria detachedCriteria, finalint 6Dst;:
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pageSize, QDE$E.a
finalint startIndex){ #epy%>
return(PaginationSupport)
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getHibernateTemplate().execute(new HibernateCallback(){ $iPP|Rw
publicObject doInHibernate ;Z9IZ~
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(Session session)throws HibernateException { CW`!}yu%
Criteria criteria = x8"#!Pw:`"
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detachedCriteria.getExecutableCriteria(session); :E'P7A
int totalCount = Yb:pAzw6
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((Integer) criteria.setProjection(Projections.rowCount z<&m*0WYA
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()).uniqueResult()).intValue(); %e_"CS
criteria.setProjection &HDP!SLS
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(null); zwr\:Hu4
List items = CdZ BG
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criteria.setFirstResult(startIndex).setMaxResults e;ty !)]
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(pageSize).list(); Tlodn7%",
PaginationSupport ps = HOZRYIQB
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new PaginationSupport(items, totalCount, pageSize, vAi$[p*im
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startIndex); *b)Q5dw@1
return ps; `78V%\
} 9[Qd)%MO
}, true); L?RF;jf
} YQ]\uT>}&
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public List findAllByCriteria(final I%lE;'x
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DetachedCriteria detachedCriteria){ `G$1n#&
return(List) getHibernateTemplate ]Pc^#=(R0
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().execute(new HibernateCallback(){ WsOi,oG@
publicObject doInHibernate <@uOCRbV
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(Session session)throws HibernateException { ]}PV"|#K{c
Criteria criteria = ]axh*J3`i
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detachedCriteria.getExecutableCriteria(session); tE"Si<[]H$
return criteria.list(); Tg
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} aT!;{+
}, true); 6}dR$*=
} BNucc']
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public int getCountByCriteria(final *"{&FEV
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DetachedCriteria detachedCriteria){ _GoVx=t
Integer count = (Integer) d- E4~)Qy
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getHibernateTemplate().execute(new HibernateCallback(){ l{WjDed
publicObject doInHibernate -yx/7B5@
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(Session session)throws HibernateException { 0$vj!-Mb^j
Criteria criteria = [_6 &N.
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detachedCriteria.getExecutableCriteria(session); qE7R4>5xjO
return H-5<S@8
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criteria.setProjection(Projections.rowCount NAFsFngqH
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()).uniqueResult(); m"/g7w4N
} 2#5,MP~r
}, true); LMl~yqM
return count.intValue(); n!ok?=(kQ
} 9'~-U
} H7g<
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用户在web层构造查询条件detachedCriteria,和可选的 9IZu$-
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 'c`jyn
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PaginationSupport的实例ps。 {1lO
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ps.getItems()得到已分页好的结果集 i%{X9!*%TX
ps.getIndexes()得到分页索引的数组 \ FzM4-
ps.getTotalCount()得到总结果数 XSRdqU>Aun
ps.getStartIndex()当前分页索引 -=}3j&,\R
ps.getNextIndex()下一页索引 /.Jb0h[W1
ps.getPreviousIndex()上一页索引 _D!g4"
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 12`_;[37
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,尤其是上面的示例代码,让我着实觉得该对我原来的分页查询做 'ktHPn
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一下代码重构了。 pd@; b5T
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我把原本我的做法也提供出来供大家讨论吧: wzWbB2Mb5
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首先,为了实现分页查询,我封装了一个Page类: fZWGn6$
java代码: t!;/Z6\Pb
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/*Created on 2005-4-14*/ YE+$H%Jl!
package org.flyware.util.page; {{yt*7k {
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/** #VbVsl
* @author Joa c9Es%@]
* ^U7OMl4Usq
*/ xyHejE}
publicclass Page { gQWd&)'muf
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/** imply if the page has previous page */ /uqu32;o
privateboolean hasPrePage; T5lQIr@a
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/** imply if the page has next page */ GJ(d&o8
privateboolean hasNextPage; UH`h OJ?
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/** the number of every page */ WgR4Ix^L#
privateint everyPage; -#&kYK#Ph
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/** the total page number */ M~
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privateint totalPage; =d;Vk
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/** the number of current page */ /i|z.nNO
privateint currentPage; N1EezC'^
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/** the begin index of the records by the current nY?
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query */ o,Z{ w"
privateint beginIndex; PFSLyV*
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/** The default constructor */ tOdT[&
public Page(){ p
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} 8s}J!/2
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/** construct the page by everyPage @ CsV]97`
* @param everyPage P<dy3;
* */ j}HFs0<L
public Page(int everyPage){ pNaiXu3
this.everyPage = everyPage; KlxN~/gyik
} B uQ|~V
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/** The whole constructor */ X~T/qFS
public Page(boolean hasPrePage, boolean hasNextPage, 9>*c_
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int everyPage, int totalPage, F}?<v8#z0
int currentPage, int beginIndex){ 3 pWM~(#>-
this.hasPrePage = hasPrePage; PBqy F
this.hasNextPage = hasNextPage; C9tb \?#
this.everyPage = everyPage; oY9FK{
this.totalPage = totalPage; wGKo.lt
this.currentPage = currentPage; Wsz0yHD[`
this.beginIndex = beginIndex; L^Wz vv]
} F#r#}.B='U
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/** 7_jE[10
* @return {eZ{]
* Returns the beginIndex. :KE/!]z
*/ h BMH)aU
publicint getBeginIndex(){ i2,U,>.
return beginIndex; x-m/SI]_N
} Pe7e?79
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/** %CH6lY=lI
* @param beginIndex }6m?d!m
* The beginIndex to set. t%0?N<9YkU
*/ x1[?5n6
publicvoid setBeginIndex(int beginIndex){ NlPS#
this.beginIndex = beginIndex; Ww9;UP'G
} eD#XDK
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/** htJuGfDx1
* @return je%M AgW`
* Returns the currentPage. 0{rx.C7|
*/ )/t6" "
publicint getCurrentPage(){ Cnh|D^{s
return currentPage; >.%4~\U
} f05d ;
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/** {[#(w75R{
* @param currentPage ocA]M=3~k
* The currentPage to set. 8e:vWgQpL
*/ V0i9DK|!
publicvoid setCurrentPage(int currentPage){ ?T'][q
this.currentPage = currentPage; wq0aF"k
} |ng%PQq)
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/** {w5Z7s0
* @return F+aQ $pQ
* Returns the everyPage. V|?WF&
*/ H'Qo\L4H
publicint getEveryPage(){ ^X1wI9V
return everyPage; bKz{wm%
} &^QPkX@p
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/** @)0 Y~A )
* @param everyPage /^<en(0=P
* The everyPage to set. Y`li> .\
*/ -Zy)5NB-tZ
publicvoid setEveryPage(int everyPage){ EZj1jpL
this.everyPage = everyPage; mnQ'X-q3iO
} \ lr/;-zP
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/** G}Z4g
* @return {BOLPE-
* Returns the hasNextPage. f_<Y\
*/ :YvbU Y
publicboolean getHasNextPage(){ Q<