Hibernate3 提供了DetachedCriteria,使得我们可以在Web层构造 a!US:^}lu
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detachedCriteria,然后调用业务层Bean,进行动态条件查询,根 ZCbnDj
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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 &gL &@';,
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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 \%FEQa0u
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分页支持类: _V`Gmy[]p
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java代码: e5 ?;{H
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package com.javaeye.common.util; O*ql!9}E{
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import java.util.List; W_E0+
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publicclass PaginationSupport { tJQFhY
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publicfinalstaticint PAGESIZE = 30; c9eLNVM
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privateint pageSize = PAGESIZE; 7jZ=+2
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privateList items; sr&hQ
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privateint totalCount; kT+Idu
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privateint[] indexes = newint[0]; 6jKZ.S+s)
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privateint startIndex = 0; {iI"Lt
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public PaginationSupport(List items, int {Di()]/
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totalCount){ H7xyK
setPageSize(PAGESIZE); $#k 8xb
setTotalCount(totalCount); ]d}U68$T+
setItems(items); QyGTm"9l
setStartIndex(0); GYX/G>-r
} 8~=<!(M)m/
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public PaginationSupport(List items, int 02lI-xHe
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totalCount, int startIndex){ ^rmcyy8;g
setPageSize(PAGESIZE); ?J<V-,i
setTotalCount(totalCount); .FarKW
setItems(items); t@`w}o[#
setStartIndex(startIndex); _i=431Z40
} DaV:Slp9
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public PaginationSupport(List items, int oM&}akPE
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totalCount, int pageSize, int startIndex){ !5hNG('f
setPageSize(pageSize); \Tc<27-
setTotalCount(totalCount); pE<@
setItems(items); _7h:NLd
setStartIndex(startIndex); g8JO/s5xV
} <@DF0x!
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publicList getItems(){ xIN&>D'|N
return items; vnNX)$f
} RZtY3:FBx|
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publicvoid setItems(List items){ {W[OjPC~F
this.items = items; OM]d}}=Y
} s7A3CY]->
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publicint getPageSize(){ 29xm66
return pageSize; X#bK.WN$
} m+t<<5I[-
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publicvoid setPageSize(int pageSize){ (9#$za>
this.pageSize = pageSize; |L@&plyB-
} 00?_10x)
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publicint getTotalCount(){ oTtJ]`T
return totalCount; H+ P&}
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} x:7"/H|
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publicvoid setTotalCount(int totalCount){ }=dUASL
if(totalCount > 0){ _M;n.?H
this.totalCount = totalCount; 4@iMGYR9!s
int count = totalCount / qT<OiIMj^
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pageSize; kq{PM-]l
if(totalCount % pageSize > 0) ")'9:c
count++; X=8CZq4
indexes = newint[count]; !CBvFl/v
for(int i = 0; i < count; i++){ \gBsAZE
indexes = pageSize * @O!BQ^'hk#
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} Ft&ARTsa*
}else{ 7s2 l 3
this.totalCount = 0; Y$vobi$
} m| /?((s
} hU3!
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publicint[] getIndexes(){ K1th>!JW'
return indexes; 6n|R<DO%\
} p;y\%i_
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publicvoid setIndexes(int[] indexes){ CAbeb+O
this.indexes = indexes; 9J*M~gKbz
} X
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publicint getStartIndex(){ >@Nn_d
return startIndex; m-<"`:+
} X,]E {
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publicvoid setStartIndex(int startIndex){ YB`;<+sY
if(totalCount <= 0) '`)r<lYN,
this.startIndex = 0; T J!d7
elseif(startIndex >= totalCount) A~@u#]]<n
this.startIndex = indexes 8 h.Dc&V
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[indexes.length - 1]; R{3?`x!fY
elseif(startIndex < 0) bAUruTn
this.startIndex = 0; O`;e^PhN
else{ [Yq*DkW
this.startIndex = indexes #OQT@uF!
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[startIndex / pageSize]; j3Sz+kOf,
} Z[,A>tJ
} kBRy(?Mft&
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publicint getNextIndex(){ qg`8f?
int nextIndex = getStartIndex() + 6>X9|w
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pageSize; QY^v*+lr\
if(nextIndex >= totalCount) >" &&,~
return getStartIndex(); mRECdGst
else 6EX_IDb
return nextIndex; NwISf
} i$z).S?1
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publicint getPreviousIndex(){ /c&;WlE/n
int previousIndex = getStartIndex() - r(VGdG
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pageSize; sTb@nrRxH
if(previousIndex < 0) 38gHM9T
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return0; * NB:"1x
else ru#CywK{{;
return previousIndex; 7 {n>0@_
} @V7HxW7RX
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} Edp%z"J;C
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抽象业务类 Ih;I&D+e;
java代码: ru 5T0w";V
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/** C-TATH%f^
* Created on 2005-7-12 K:JM*4W
*/ 4g "_E
package com.javaeye.common.business; zz7#gU
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import java.io.Serializable; m%p;>:"R
import java.util.List; pR,eus;8
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import org.hibernate.Criteria; 79bt%P
import org.hibernate.HibernateException; /7o{%~O
import org.hibernate.Session; 9R1S20O
import org.hibernate.criterion.DetachedCriteria; u&npUw^Va
import org.hibernate.criterion.Projections; p(8[n^~,i
import "%?$BoJR0
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org.springframework.orm.hibernate3.HibernateCallback; \G~<O071
import Z{ AF8r
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org.springframework.orm.hibernate3.support.HibernateDaoS Ltrw)H}
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upport; a^>e|Eq|
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import com.javaeye.common.util.PaginationSupport; .zQ'}H1.C
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public abstract class AbstractManager extends px~ :'U
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HibernateDaoSupport { lI&5.,2MP
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privateboolean cacheQueries = false; TEEt]R-y
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privateString queryCacheRegion; upc-Qvk
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publicvoid setCacheQueries(boolean h)o5j-M>4
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cacheQueries){ -h`[w:
this.cacheQueries = cacheQueries; iYR`|PJi
} +)06*"I
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publicvoid setQueryCacheRegion(String 8IQqDEY^
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queryCacheRegion){ SbX#$; ks~
this.queryCacheRegion = *vS)aRK
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queryCacheRegion; 5@/hqOiu
} 6qYK"^+xu
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publicvoid save(finalObject entity){ L_(Y[!
getHibernateTemplate().save(entity); /@xL {
} .{t]Mc
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publicvoid persist(finalObject entity){ hha!uD~(
getHibernateTemplate().save(entity); dZ;rn!dg>
} s^lm
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publicvoid update(finalObject entity){ U_oei3QP
getHibernateTemplate().update(entity); CeD(!1VG
} k>W}9^ cK
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publicvoid delete(finalObject entity){ #}8 x
getHibernateTemplate().delete(entity); [`/d$V!e
} KpF/g[m
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publicObject load(finalClass entity, !IAd.<,
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finalSerializable id){ p/4}SU
return getHibernateTemplate().load Q?WgGE4>
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(entity, id); 'ngx\Lr
} 7a5G,C#QQ
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publicObject get(finalClass entity, 9zac[tno
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finalSerializable id){ \ x>#bql+
return getHibernateTemplate().get 227 Z6#CF!
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(entity, id); G}NT[
} d.:.f_|
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publicList findAll(finalClass entity){ VcpN
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return getHibernateTemplate().find("from _a&Mk
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" + entity.getName()); OtD!@GQ6
} Q|&Wcxq2!
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publicList findByNamedQuery(finalString $?Z-BD1
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namedQuery){ VU ,tCTXz
return getHibernateTemplate <cNg_ZZ;8
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().findByNamedQuery(namedQuery); :!WKD@]
} -h1FrDBt
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publicList findByNamedQuery(finalString query, ^h~oxZJw
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finalObject parameter){ P d)<Iw^<
return getHibernateTemplate -$@4e|e%a
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().findByNamedQuery(query, parameter); g6l&;S40
} q%\rj?U_
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publicList findByNamedQuery(finalString query, w8298Kl
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finalObject[] parameters){ n}!D)Gx
return getHibernateTemplate 03^?+[C
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().findByNamedQuery(query, parameters); ly)L%hG
} `@#,5S$ E
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publicList find(finalString query){ ,W:Bh$%
return getHibernateTemplate().find K.I\E
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(query); >^(Q4eU7!
} 3E`poE
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publicList find(finalString query, finalObject a]nyZdt`
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parameter){ 81&5g'
return getHibernateTemplate().find r5(-c]E7
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(query, parameter); W
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} 1 6G/'Hb
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public PaginationSupport findPageByCriteria lL]8~3b
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(final DetachedCriteria detachedCriteria){ XJ9bY\>)q1
return findPageByCriteria 3GUJlFj
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(detachedCriteria, PaginationSupport.PAGESIZE, 0); 2}HS`) /
} b{i7FRR>o4
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public PaginationSupport findPageByCriteria -Yf pfNt
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(final DetachedCriteria detachedCriteria, finalint 3G9AS#-C
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startIndex){ ~n$e
return findPageByCriteria f[$9k}.
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(detachedCriteria, PaginationSupport.PAGESIZE, ;zZGV4Qc~
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startIndex); +ziQ]r2g
} Tx!c}
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public PaginationSupport findPageByCriteria i~04 P
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(final DetachedCriteria detachedCriteria, finalint .-W_m7&}
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pageSize, ecgGl,{
finalint startIndex){ "Ca?liy
return(PaginationSupport) 2 -
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getHibernateTemplate().execute(new HibernateCallback(){ v\ gCgx=%j
publicObject doInHibernate -+#g.1UL/
)/1,Ogb%_
(Session session)throws HibernateException { Z-BPC|e
Criteria criteria = K;}h
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detachedCriteria.getExecutableCriteria(session); #H1ng<QV
int totalCount = v4V|j<R
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((Integer) criteria.setProjection(Projections.rowCount 5
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()).uniqueResult()).intValue(); std4Nyp
criteria.setProjection sG~5O\,E
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(null); Gj}P6V_
List items = _'lrI23I
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criteria.setFirstResult(startIndex).setMaxResults s]p3dB#
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(pageSize).list(); zXH CP.Rmg
PaginationSupport ps = (!0=~x|Z[
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new PaginationSupport(items, totalCount, pageSize, SmJ6Fm6
I8 \Ka=w
startIndex); aykNH>#Po
return ps; m+J3t@$
} M6+_Mi.
}, true); h) .([
} B3V=;zn3
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public List findAllByCriteria(final f9Hm2wV
{t;{={$
DetachedCriteria detachedCriteria){ b6k'`vLA
return(List) getHibernateTemplate v!pT!(h4
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().execute(new HibernateCallback(){ 3Hli^9&OX_
publicObject doInHibernate ^BruRgc+
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(Session session)throws HibernateException { ,\FJVS;NeJ
Criteria criteria = Y M_\ ZK:
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detachedCriteria.getExecutableCriteria(session); 4?AggqW
return criteria.list(); 6J|Y+Y$
} 4D`T_l
}, true); fdD?"z
} U0+Hk+
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public int getCountByCriteria(final s C9j73vf
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DetachedCriteria detachedCriteria){ s9wcZO
Integer count = (Integer) @Ee'nP
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getHibernateTemplate().execute(new HibernateCallback(){ ,4-) e
publicObject doInHibernate C#<:x!
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(Session session)throws HibernateException { \I@=EF- &
Criteria criteria = 8-?.Q"D7%
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detachedCriteria.getExecutableCriteria(session); DFz,>DM;
return oXc!JZ^
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criteria.setProjection(Projections.rowCount 8gv\`
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()).uniqueResult(); T'cahkSw'O
} >C`b4xQ
}, true); 1A4!zqT;
return count.intValue(); K.Tfu"6
} .O{2]e$
} LsnM5GU7
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用户在web层构造查询条件detachedCriteria,和可选的 C|"h]
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startIndex,调用业务bean的相应findByCriteria方法,返回一个 S=>54!{`x
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PaginationSupport的实例ps。 &i8AB{OU
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ps.getItems()得到已分页好的结果集 iw\RQ
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ps.getIndexes()得到分页索引的数组 G SXe=?
ps.getTotalCount()得到总结果数 ISI\<qx
ps.getStartIndex()当前分页索引 8'Z#sM^E
ps.getNextIndex()下一页索引 " r!O9X6
ps.getPreviousIndex()上一页索引 FY [WdZDZ
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连续看了两篇robbin有关DetachedCriteria的介绍,感觉真的不错 :=BFx"Y
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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 ErK5iTSD
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一下代码重构了。 /vi>@a
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我把原本我的做法也提供出来供大家讨论吧: L'LZK
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首先,为了实现分页查询,我封装了一个Page类: :?s~,G_*l
java代码: M-3kF"
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/*Created on 2005-4-14*/ Z5re Fok
package org.flyware.util.page; %O`e!p
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/** nc#}-}`5
* @author Joa s
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* 3%Z:B8:<