Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 2+8#H.
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 .?C%1a&_l
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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 "T/>d%O1b
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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 4NVV5_K a
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。 4NEq$t$Jn
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分页支持类: f}%D"gz
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java代码: vP!GJX&n5
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package com.javaeye.common.util; :
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import java.util.List; rk2xKm^w
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publicclass PaginationSupport { C@y8.#l
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publicfinalstaticint PAGESIZE = 30; qgt[ ~i*
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privateint pageSize = PAGESIZE; :)f7A7 :;
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privateList items; Lr;(xw\['
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privateint totalCount; Lju7,/UD
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privateint[] indexes = newint[0]; Y+%sBqo@
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privateint startIndex = 0; F^aR+m
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public PaginationSupport(List items, int W~T}@T:EN
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totalCount){ !{,F~i9
setPageSize(PAGESIZE); EC&@I+'8Q
setTotalCount(totalCount); ;|%dY{L-
setItems(items); n#Dv2 E=6
setStartIndex(0); gB,G.QM*6
} :S@1
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public PaginationSupport(List items, int }]1BO
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totalCount, int startIndex){ <hnCUg1
setPageSize(PAGESIZE);
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setTotalCount(totalCount); Fh7'[>onw
setItems(items); 0Y=![tO8
setStartIndex(startIndex); oj,lz?
} FX<b:#
}!#gu3
public PaginationSupport(List items, int IHfzZHy
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totalCount, int pageSize, int startIndex){ MjfFf} @
setPageSize(pageSize); l*b)st_p%
setTotalCount(totalCount); oz'\q0
setItems(items); !M<{E*
setStartIndex(startIndex); - "*r
} 23(=Xp3;>
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publicList getItems(){ 31+;]W=
return items; {Ee>n^1
} v;#=e$%}MO
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publicvoid setItems(List items){ ?eV(1Fr@
this.items = items; .V9e=yW!*
} zboF
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publicint getPageSize(){ C8N{l:1f]
return pageSize; Hk_y/97OO
} v}G]X Z8
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publicvoid setPageSize(int pageSize){ _?7#MWe&
this.pageSize = pageSize; C9n}6Er=,
} jt~Qu-
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publicint getTotalCount(){ "bg'@:4F
return totalCount; g3@Rl2yQJ
} 3b'tx!tFN
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publicvoid setTotalCount(int totalCount){ Z{IUy
if(totalCount > 0){ 0rk]/--FGJ
this.totalCount = totalCount; jcCoan
int count = totalCount / \hO2p6
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pageSize; fqz28aHh
if(totalCount % pageSize > 0) C`rLj5E%
count++; e)nimq
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indexes = newint[count]; G |*(8r()
for(int i = 0; i < count; i++){ qVjWV$j
indexes = pageSize * FFhtj(hVgc
1
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} gV1[3dW
}else{ ?71+f{s
this.totalCount = 0; (%CZ*L[9Z
} Ph&urxH@
} F1;lQA*7K.
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publicint[] getIndexes(){ fjo{av~]y
return indexes; {C`GW}s{4
} 3OyS8`
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publicvoid setIndexes(int[] indexes){ P=N$qz$U
this.indexes = indexes; 5OIc(YhYf
} K)7zKEp`cj
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publicint getStartIndex(){ -${DW^txMZ
return startIndex; 6[qA`x#
} 1L7{p>;-dO
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publicvoid setStartIndex(int startIndex){ J;t 7&Zpe
if(totalCount <= 0) .%EL \2
this.startIndex = 0; Rx07trfN
elseif(startIndex >= totalCount) =*BIB5
this.startIndex = indexes {
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[indexes.length - 1]; ;?fS(Vz~
elseif(startIndex < 0) .@)mxC:\K9
this.startIndex = 0; lA!"z~03*
else{ *F^wtH`
this.startIndex = indexes 9L0GLmLk1u
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[startIndex / pageSize]; D(W,yq~7uY
} `Ycf]2.,$
} R9We/FhOY
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publicint getNextIndex(){ u*S=[dq
int nextIndex = getStartIndex() + qIUfPA=/_
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pageSize; R;whW:Tx
if(nextIndex >= totalCount) gieN9S
return getStartIndex(); Z0!5d<
else L(S'6z~_9
return nextIndex; z2gk[zY&
} Zv]x'3J#Y
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publicint getPreviousIndex(){ -Lu)'+
int previousIndex = getStartIndex() - 'z@ 0
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pageSize; c'6g*%2k
if(previousIndex < 0) 'XQ`g CF=
return0; <oKGD50#
else vgt]:$
return previousIndex; m ~#!
} :,;K>l^U
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} 'k;4 j|<
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抽象业务类 e"]8T},
java代码: W/z7"#
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/** {%)s.5Pfw
* Created on 2005-7-12 [%~
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package com.javaeye.common.business; 5wB =>
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import java.io.Serializable; ~I/@i
import java.util.List; M}:=zcZ l
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import org.hibernate.Criteria; j hYToMq
import org.hibernate.HibernateException; _LP/!D
import org.hibernate.Session; X)SDG#&+bF
import org.hibernate.criterion.DetachedCriteria; 3P~o"a>
import org.hibernate.criterion.Projections;
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import (@X~VACT
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org.springframework.orm.hibernate3.HibernateCallback; fy@avo9
import Dih6mTP{
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org.springframework.orm.hibernate3.support.HibernateDaoS ^L1L=c;,
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upport; 76tdJ!4Z
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import com.javaeye.common.util.PaginationSupport; Sw^X2$h
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public abstract class AbstractManager extends AIb2k
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HibernateDaoSupport { ^
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privateboolean cacheQueries = false; gM>t0)mGK
{ pu85'DV
privateString queryCacheRegion; ERwHLA
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publicvoid setCacheQueries(boolean ')a(.f
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cacheQueries){ j.a`N2]WE
this.cacheQueries = cacheQueries; jA".r'D%
} ZnFi<@UB)
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publicvoid setQueryCacheRegion(String wIkN9
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queryCacheRegion){ O/:UJ( e{
this.queryCacheRegion = )%rg?lI
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queryCacheRegion; 4tg<iH{
} XxHx:mi
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publicvoid save(finalObject entity){ 5tQ1fJze
getHibernateTemplate().save(entity); aKU*j9A?;Z
} Q
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publicvoid persist(finalObject entity){ 8x`.26p
getHibernateTemplate().save(entity); xI,2LGO
} Sxjub&=
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publicvoid update(finalObject entity){ FZreP.2)!
getHibernateTemplate().update(entity); vVGDDDz/
} _%'},Xd.z
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publicvoid delete(finalObject entity){ ?!qY,9lhH
getHibernateTemplate().delete(entity); wf,7==
} TJE\A)|>g
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publicObject load(finalClass entity, /iG*)6*^k
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finalSerializable id){ P"sA
return getHibernateTemplate().load p=/m
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(entity, id); Q{e\}wN
} :Xc@3gF
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publicObject get(finalClass entity, zy*/T>{#
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finalSerializable id){ 9&<x17'
return getHibernateTemplate().get B|o2K}%f
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(entity, id); T843":
} F~ Lx|)0M
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publicList findAll(finalClass entity){ JNcYJ[wqv
return getHibernateTemplate().find("from j}b\Z9)!
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" + entity.getName()); lRh9j l
} 3D?sL!W
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publicList findByNamedQuery(finalString z;@*r}H
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namedQuery){ !8`3GX:B_
return getHibernateTemplate SkU9ON
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().findByNamedQuery(namedQuery); U]a*uF~h
} ){jla,[
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publicList findByNamedQuery(finalString query, m N8pg4
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finalObject parameter){ ~
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return getHibernateTemplate phO;c;y}
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().findByNamedQuery(query, parameter); _X?^Cy
} ctcS:<r/3@
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publicList findByNamedQuery(finalString query, qZ@s#UiB
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finalObject[] parameters){ vq34/c^
return getHibernateTemplate =B.F;40
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().findByNamedQuery(query, parameters); I%urz!CNE*
} U*.0XNKp{
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publicList find(finalString query){ J90v!p-
return getHibernateTemplate().find YJ$1N!rG
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(query); -*.-9B~u
} Ar~"R4!
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publicList find(finalString query, finalObject kQ]$%Lk[
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parameter){ v+99
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return getHibernateTemplate().find F2X0%te
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(query, parameter); O$4yAaD
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} >LDhU%bH
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public PaginationSupport findPageByCriteria eF2|Wjl``;
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(final DetachedCriteria detachedCriteria){ =*Bl|;>6
return findPageByCriteria /*0K92NB
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); hpU2
} 2;w*oop,O
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public PaginationSupport findPageByCriteria ~Jf{4*>y
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(final DetachedCriteria detachedCriteria, finalint j&k6O1_
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startIndex){ +
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return findPageByCriteria G8Du~h!!U
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(detachedCriteria, PaginationSupport.PAGESIZE, Nz)l<S9>
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startIndex); <_Q1k>
} d^`?ed\1
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public PaginationSupport findPageByCriteria m^qBxA
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(final DetachedCriteria detachedCriteria, finalint 5 (A5Y-B
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pageSize, !F?XLekTi
finalint startIndex){ ~y7jCcd`
return(PaginationSupport) $q 2D+_
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getHibernateTemplate().execute(new HibernateCallback(){ M9f35
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publicObject doInHibernate &iV{:)L
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(Session session)throws HibernateException { PdvqDa8
Criteria criteria = `jOX6_z?I
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detachedCriteria.getExecutableCriteria(session); B/n[m@O
int totalCount = GAAm0;
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((Integer) criteria.setProjection(Projections.rowCount :<|<|qJWo
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()).uniqueResult()).intValue(); jq!tT%o*B
criteria.setProjection =)7s $
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(null); /Ju;MeE9
List items = vI@%Fg+D
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criteria.setFirstResult(startIndex).setMaxResults =lpQnj"
3*@5S]]
(pageSize).list(); Sr?#S
PaginationSupport ps = QNl'ZB\
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new PaginationSupport(items, totalCount, pageSize, \W`w` o
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startIndex); [VWUqlNt>
return ps; Rx+p.
} )[Yv?>ib
}, true); R,Vd.-5M
} y.Z?LCd<
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public List findAllByCriteria(final <=,6p>Eo[
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DetachedCriteria detachedCriteria){ G2FXrkU
return(List) getHibernateTemplate d0,s"K7@
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().execute(new HibernateCallback(){ G}G#i`6o
publicObject doInHibernate P$-X)c$&
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(Session session)throws HibernateException { nxl[d\ap+n
Criteria criteria = E^SH\5B
(!zy{;g|
detachedCriteria.getExecutableCriteria(session); E)fglYWs2
return criteria.list(); h?azFA~
} 0/oyf]HR
}, true); L:'J
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} *VZ5B<Ic
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public int getCountByCriteria(final "l*`>5Nn9
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DetachedCriteria detachedCriteria){ o+$7'+y1n-
Integer count = (Integer) ~7Tc$
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getHibernateTemplate().execute(new HibernateCallback(){ QhK#Y{xY
publicObject doInHibernate d8x \
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(Session session)throws HibernateException { {7/0< NG
Criteria criteria = c*@E_}C#
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detachedCriteria.getExecutableCriteria(session); _Iv6pNd/
return }I2@%tt?
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criteria.setProjection(Projections.rowCount ut I"\1hQ
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()).uniqueResult(); k4[|'Dk?
} }-6)gWe
}, true); y)@[Sl>
return count.intValue(); `u&Zrdr,
} KSNPkd6
} c. 2).Jt,
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用户在web层构造查询条件detachedCriteria,和可选的 ikSt"}/hd
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 07^iP>?
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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 9uA>N
ps.getIndexes()得到分页索引的数组 I\$X/t +dH
ps.getTotalCount()得到总结果数 f__cn^1
ps.getStartIndex()当前分页索引 De(Hw&
IV
ps.getNextIndex()下一页索引 aD$v2)RR
ps.getPreviousIndex()上一页索引 c:o]d )S
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 S9~+c
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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 zM(vr"U
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一下代码重构了。 %~E ?Z!_W
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我把原本我的做法也提供出来供大家讨论吧: vRHd&0
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首先,为了实现分页查询,我封装了一个Page类: g9Xu@N;bL
java代码: IV\'e}
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/*Created on 2005-4-14*/ Z:sg}
package org.flyware.util.page; 4O )1uF;
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/** P'Ux%Q+B>
* @author Joa (2^gVz=j
* 3 I@}my1
*/ ]dGw2y
publicclass Page { \%f q
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/** imply if the page has previous page */ lFV N07hG
privateboolean hasPrePage; Af'" 6BS
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I
/** imply if the page has next page */ 3c]b)n~Y
privateboolean hasNextPage; [BqHx5Xz(
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/** the number of every page */ @,cowar*
privateint everyPage; ,^w?6?,&l}
$m].8?
/** the total page number */ 3L_\`Ia9
privateint totalPage; a1t4Dd
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/** the number of current page */ s'E2P[:
privateint currentPage; 1DE<rKI
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/** the begin index of the records by the current ]yx$(6_U
E[@ u
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query */ D6>2s\:>vp
privateint beginIndex; $JJrSwR<h
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/** The default constructor */ )FF>IFHG
public Page(){ uW@oyZUj
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} T>x&T9
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/** construct the page by everyPage 7VqM$I
* @param everyPage njScz"L~
* */ ;#xmQi'`
public Page(int everyPage){ 6K-_pg]
this.everyPage = everyPage; OWjk=u2Lz
} E:JJ3X|
yp KUkH/
/** The whole constructor */ wKZ$iGMbz
public Page(boolean hasPrePage, boolean hasNextPage, 7\$qFF-y
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e vrXo"3
int everyPage, int totalPage, i'H/ZwU
int currentPage, int beginIndex){ )uj Ex7&c
this.hasPrePage = hasPrePage; <>s`\ %
this.hasNextPage = hasNextPage; &x[E;P*Fg
this.everyPage = everyPage; P&9Gga^I
this.totalPage = totalPage; KIui(n#/
this.currentPage = currentPage; uC+V6;
this.beginIndex = beginIndex; l6YtEHNG
} I/d&G#:~
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/** *c~T@m~DR
* @return { /K.3
* Returns the beginIndex. 0fF(Z0R,
*/ R:e<W/P"
publicint getBeginIndex(){ q qpgy7
return beginIndex; 5R'TcWf#W
} NO|KVZ~
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/** T]t+E'sQ
* @param beginIndex [5zx17'
* The beginIndex to set. ,sA[)wP {
*/ YP.5fq:
publicvoid setBeginIndex(int beginIndex){ Ge-CY
this.beginIndex = beginIndex; eqP&8^HP
} 7ePqmB<.
0vEoGgY0*:
/** vy0X_DPCr
* @return l)Pu2!Ic
* Returns the currentPage. 1<BX]-/tP
*/ 4{hps.$?~
publicint getCurrentPage(){ X%Z{K-
return currentPage; @y='^DQ*
} 9:ze{ c $
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/** :"=ez<t
* @param currentPage wF <n=
* The currentPage to set. XWA:J^
*/ D2](da:]8)
publicvoid setCurrentPage(int currentPage){ N}pw74=1
this.currentPage = currentPage; ~%^
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} bu:S:`
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/** ;'5>q&[qbP
* @return (d(hR0HKE
* Returns the everyPage. AvdXEY(-
*/ 7![,Q~Fy
publicint getEveryPage(){ +Vm}E0Ov
return everyPage; 2q3+0Et8
} )Y2{_ bx4"
Gnfd;.
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/** 4US"hexE<
* @param everyPage ^cczJOxB
* The everyPage to set. ^aH\7J@Y
*/ 5jd,{<
publicvoid setEveryPage(int everyPage){ 4a'N>eDR
this.everyPage = everyPage; r<K(jG[:{f
} txiP!+3OWB
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/** RRRCS]y7$t
* @return 4*Q#0`um
* Returns the hasNextPage. ^.1c{0Y^0
*/ 7on.4/;M
publicboolean getHasNextPage(){ =x<ge _Y
return hasNextPage; {DU`[:SQZg
} oASY7k_3
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/** 2$?C7(kW
* @param hasNextPage |/09<F:L[
* The hasNextPage to set. x$1]M DAGb
*/ fb{``,nO
publicvoid setHasNextPage(boolean hasNextPage){ RLbKD>
this.hasNextPage = hasNextPage; m=}B,']O
} p?B=1vn-2
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/** l-SAC3qhG
* @return &;+-?k|
* Returns the hasPrePage. KVD8YfF
*/ [-\%4
publicboolean getHasPrePage(){ ^:#D0[
return hasPrePage; kuol rfGB
} ;?8_G%va
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/** fjU8gV
* @param hasPrePage $lLz3YS
* The hasPrePage to set.
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*/ }
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publicvoid setHasPrePage(boolean hasPrePage){ `}mcEl
this.hasPrePage = hasPrePage; K Pt5=a
} byTh/ H
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/** i(iXD
* @return Returns the totalPage. "f "6]y
* o| #Qu8Lk
*/ c
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publicint getTotalPage(){ 4WJ.^ (
return totalPage; huJ&]"C
} d5oIH
'=Rs/EDME
/** z"0I>gl
* @param totalPage 8Le||)y,\
* The totalPage to set. (>r[-Bft
*/ Cq%IE^g<
publicvoid setTotalPage(int totalPage){ ||;hciO
this.totalPage = totalPage; <$X3Hye
} BZR:OtR^
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} CitDm1DXt/
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K?BOvDW"`
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 B]uc<`f
CE/Xfh'44
个PageUtil,负责对Page对象进行构造: mT.u0KUIy
java代码:
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/*Created on 2005-4-14*/ 8$0rR55
package org.flyware.util.page; \3pc"^W
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import org.apache.commons.logging.Log; paKSr|O
import org.apache.commons.logging.LogFactory; }Q=!Y>Tc
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/** vvKEv/pN7
* @author Joa Y?(r3E^x
* iZM+JqfU|D
*/ hFH*B~*:#
publicclass PageUtil { {=F/C,-
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privatestaticfinal Log logger = LogFactory.getLog S/4^ d &Gr
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(PageUtil.class); Sgp;@4`M
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/** >_|O1H./4
* Use the origin page to create a new page ][?G/*k
* @param page Ry%Mej:
* @param totalRecords .6`9H 1
* @return &(xH$htv1
*/ i 7x7xtq
publicstatic Page createPage(Page page, int L{h%f4Du#
vTlwRG=5
totalRecords){ L#+q]j+
return createPage(page.getEveryPage(),
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page.getCurrentPage(), totalRecords); ?TU }~}
} (2:/8\_P
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