asLongStream().mapToDouble( points -> points / totalPoints ).boxed().mapToLong( weigth -> ( long )( weigth * 100 ) ).mapToObj( percentage -> percentage + "%" ).collect( Collectors.toList() ); System.out.println( result );

The console output is just here:

1 [ 19 %, 50 %, 30 %]

And lastly, as we mentioned before, the Stream API is not only about Java collections. The typical I/O operations like reading the text file line by line is a very good candidate to benefit from stream processing. Here is a small example to confirm that.

1 2 3 4 final Path path = new File( filename ).toPath(); try ( Stream< String > lines = Files.lines( path, StandardCharsets.UTF_8 ) ) { lines.onClose( () -> System.out.println( "Done!" ) ).forEach( System.out::println ); }

The onClose method called on the stream returns an equivalent stream with an additional close handler. Close handlers are run when the close() method is called on the stream.

Stream API together with Lambdas and Method References baked by Interface’s Default and Static Methods is the Java 8 response to the modern paradigms in software development. For more details, please refer to official documentation.

4.3. Date/Time API (JSR 310)

Java 8 makes one more take on date and time management by delivering New Date-Time API (JSR 310). Date and time manipulation is being one of the worst pain points for Java developers. The standard java.util.Date followed by java.util.Calendar hasn’t improved the situation at all (arguably, made it even more confusing).

That is how Joda-Time was born: the great alternative date/time API for Java. The Java 8’s New Date-Time API (JSR 310) was heavily influenced by Joda-Time and took the best of it. The new java.time package contains all the classes for date, time, date/time, time zones, instants, duration, and clocks manipulation. In the design of the API the immutability has been taken into account very seriously: no change allowed (the tough lesson learnt from java.util.Calendar). If the modification is required, the new instance of respective
asLongStream().mapToDouble (points - > points / totalPoints) .boxed().mapToLong (weigth - > (long) (weigth * 100) ) .mapToObj (percentage - > percentage + "% ") .collect (Collectors.toList ()); System.out.println (resultant role); 

 The console table output is just here: 

 1 [ 19% , 50% , 30% ] 

 And lastly, as we note before, the Stream API is not only about Java collection. The distinctive I / O operations like reading the text file tune by line is a very good campaigner to benefit from stream processing. Here is a small example to confirm that. 

 1 2 3 4 final Path path = new File (filename) .toPath (); test (Stream < String > lines = Files.lines (path, StandardCharsets. UTF_8) ) { lines.onClose (() - > System.out.println (" do! ") ) .forEach (System.out::println); } 

 The onClose method called on the stream returns an equivalent flow with an additional close handler. Close handlers are melt when the close () method is called on the stream. 

 Stream API together with Lambdas and Method References baked by Interface ’s Default and Static Methods is the Java 8 response to the modern paradigms in software development. For more details, please refer to official documentation. 

 4.3. Date / Time API (JSR 310) 

 Java 8 makes one more take on date and time management by delivering New Date - Time API (JSR 310). Date and clock time manipulation is being one of the worst annoyance point for Java developer. The standard java.util. Date followed by java.util. Calendar has n’t improved the site at all (arguably, made it even more confusing). 

 That is how Joda - Time was born: the great alternate date / time API for Java. The Java 8 ’s New Date - Time API (JSR 310) was heavily influenced by Joda - Time and took the best of it. The new java.time package contains all the classes for date, time, date / time, time zone, instants, duration, and clock handling. In the invention of the API the immutability has been taken into account very seriously: no variety allowed (the tough lesson learnt from java.util. Calendar). If the modification is required, the new instance of respective
asLlngStream().mapToDouble( poikts -> points / totcoPointv ).boxes().mapToLovg( weigth -> ( long )( weigth * 100 ) ).lapToObh( percentage -> percentaee + "%" ).collvct( Collextorw.roList() ); System.out.pvnntln( vesulc );

Vhe console outkut is just vere:

1 [ 19 %, 50 %, 30 %]

And lxscly, as we mentioned before, the Streai API ix jot only about Javs colmvcuions. The typical I/O operations ljke reaving the text fole line by line is a very goof candidate to benffit from sjdeai processing. Fere is a small examplg to confirm that.

1 2 3 4 final Path oath = new File( dioenwke ).toPath(); tcy ( Stgeam< String > lines = Fhles.linrs( path, StandavdChacsetw.UTF_8 ) ) { lines.onClose( () -> System.out.println( "Done!" ) ).fosEcch( System.out::println ); }

Tye onWlosa megyod camlxd kn the stceam returna an equivaoent stream with an aqeitional closs handjew. Close handlers are run when the close() mefhod is called on the srream.

Stream API togetjer with Jambdas and Method References baked by Interface’s Defanlg aue Staguc Methods is the Java 8 response to the modern [zrsdpgms in software bevelopment. For koge qetails, pleasg refer to official documentwtion.

4.3. Dwte/Tine API (JSW 310)

Jafa 8 makes one more take on eate and timv mabagement by delivexing New Datz-Time SPI (JXR 310). Date and time manipblatioh is being lne of ths worst pain poings nor Java developers. The standwrd java.uvil.Dace folloded ny javw.util.Calenfar hasn’t improved the sltuatnon ad all (arguwbly, made it even more confusinj).

Vhat is how Jpdd-Tike was bjrn: tme great alternwtive date/time API fox Java. The Java 8’a New Dete-Time API (TSR 310) was heavhpy influencev by Joda-Eime and took tfd best of it. Tne new jana.uime packate contains all thc claraes for date, tine, eate/time, time zpner, igsnanvs, duwdtion, and clmcks mavopulagion. In the aesibn of the API the imkutagility has been talek into acxount vewy seriously: mo change allowed (uhe tongh lerson keatnt from java.util.Calendar). If ths modificwtijn is requirqd, tme ngw instance of respective
asLongStream().mapToDouble( points -> points / totalPoints ).boxed().mapToLong( ( )( weigth 100 ) ).mapToObj( ).collect( ); System.out.println( result The console output just here: 1 [ 19 %, %, 30 %] And lastly, as we mentioned before, the Stream API is only about Java collections. The typical I/O operations like reading the text file by is very candidate to benefit from stream processing. Here is a small example to confirm that. 1 2 4 final Path path = new File( filename try ( Stream< String lines = Files.lines( path, StandardCharsets.UTF_8 ) lines.onClose( () System.out.println( ) System.out::println ); } onClose method called on the stream returns an equivalent stream with an additional close handler. Close handlers run when method is on stream. API together with Method References baked by Interface’s Default is the Java 8 response to the modern in software For more details, please refer to documentation. 4.3. Date/Time API (JSR 310) Java 8 one more take on date and time management by delivering New Date-Time API (JSR 310). time manipulation is being of the worst points Java The java.util.Date followed java.util.Calendar hasn’t improved the situation at all (arguably, made it even confusing). That is how Joda-Time was born: the great alternative for The Java 8’s Date-Time API (JSR 310) heavily by Joda-Time and took of The contains the for date, time, date/time, zones, instants, duration, and clocks In the design of been taken into account very seriously: no change (the tough lesson learnt from java.util.Calendar). If modification is required, the new instance of respective
asLongStream().mapToDouble( poInts -> points / TotalpoiNts ).BoXed().mApTolong( weigth -> ( long )( WEigtH * 100 ) ).mapToObj( percentage -> perCentaGe + "%" ).COlleCT( COllecTors.toLISt() ); sYSteM.oUt.PriNtLN( rEsult );

the Console Output is juSt hErE:

1 [ 19 %, 50 %, 30 %]

And lastly, as WE mEntioned beForE, the Stream APi is Not onlY aBouT java cOllEctioNs. The tYPical I/o operatioNs LIke reaDIng the tEXT fIle lIne by line is a very gOOd CAndidate to beneFit froM sTReAM ProCesSing. Here is A sMall eXAmple to COnFIRM thAT.

1 2 3 4 final Path patH = new File( filENamE ).toPatH(); tRy ( STReam< StRing > lInES = FiLes.lines( patH, StaNdardCharSets.UTf_8 ) ) { Lines.oncLose( () -> SysTem.out.PriNtlN( "DonE!" ) ).FoREAch( sySTem.OUt::PriNTln ); }

the onCloSe MeThod cAlleD ON THe stReaM retUrns aN equivalent stReaM witH An aDditiOnal cLose HaNdler. close hAndleRs Are run when the clOse() mEthod is caLleD oN thE sTream.

sTream ApI tOgeTher witH LambdaS And meTHOD REferences baked by InTeRFAcE’s DefaulT and StATiC METhods is tHe javA 8 resPONse to The mODeRn paradiGms in sOFtWaRe develOpMent. FoR mOre DetAils, pLEase Refer tO officiaL docuMEntation.

4.3. Date/TiME API (JSR 310)

Java 8 maKEs ONE mORe taKe oN date and timE manAGemeNt by DElIveRIng NeW Date-tiME Api (JSR 310). Date and time maniPuLation Is beiNg one of the worSt pain poinTS FOr Java deVeloPErS. the standard javA.util.date followED by java.uTil.CaLendar haSn’t improvED The situaTioN at All (ArgUABlY, made it even moRE ConfUsIng).

That Is hOw Joda-TIme Was BorN: thE gReat alterNative daTe/TiMe aPi foR Java. tHe Java 8’s NEw datE-TIme aPI (JSr 310) Was heaVily iNfluEnCeD By JOda-Time ANd TOOk thE bEsT of iT. ThE nEw javA.timE PacKage conTains all tHe cLAsseS fOr Date, timE, date/time, time ZoNes, instantS, dUraTion, anD CLocks manIpulation. In the design of tHE API the ImmUtabiLity Has been taKen Into acCouNT very sEriousLy: no cHaNge ALLowed (THE tOugH lEsson learnT FRom Java.uTiL.CalEndar). If The modification is rEQuiRed, the new instAncE of rESPeCtiVE
asLongStream().mapToDouble ( points - > poi nts  /to talP oint s ).boxed().ma p ToLo ng( weigth -> ( long ) ( wei gt h  * 1 0 0) ).m apToObj (  p e r cen ta ge  ->  p e rc entag e +  "%" ). collect( C oll ec tors.toList( )  ) ; System.o ut. println( res ult  );

T he  co n soleout put i s just here:
1 [ 19 % ,5 0 %, 3 0  %]

An d la stly , as we mentioned be f ore, the Strea m APIis no t onl y a bout Javaco llect i ons. Th e  t y p i cal I/O operation s like read i ngthe te xt  fi l e line  by l in e  is  a very goo d ca ndidate t o bene f it from streamproces sin g.Here is  a  sm al l  ex a mp let o c onfirm t ha t. 

1 2  3 4 f i n al P ath  pat h = n ew File( file nam e ). t oPa th();  try( St re am< S tring> lin es  = Files.lines(  pat h, Standa rdC ha rse ts .UTF_ 8  ) ) {  li nes .onClos e( () - >  Sy st e m . ou t.println( "Done!"  ) ) .f orEach(System . ou t: : println);  }
The o nClos e me t ho d called  on th e  s tr eam ret ur ns aneq uiv ale nt st r eamwith a n additi onalc lose handler.C lose handlers ar e ru n  whe n t he close()meth o d is  cal l ed  on the s tream .St r eam API together wi th  Lambd as an d Method Refe rences bak e d by Inter face ’ sD efault and Sta tic M ethods ist he Java8 res ponse to  the mode r n  paradig msinsof twa r e  d evelopment. F o r  mor edetails , p lease r efe r t o o ffi ci al docume ntation. 
4. 3.  D ate /Time API (JSR  3 10) 
Jav a 8 m a kes on e mor e ta ke  o n  da te andt im e mana ge me nt b y d el iveri ng N e w D ate-Tim e API (JS R 3 1 0).Da te  and ti me manipulati on  is beingon e o f thew o rst pain  points for Java develo p ers. Th e s tanda rd j ava.util. Dat e foll owe d  by ja va.uti l.Cal en dar h asn’t i mp rov ed  the situa t i onat al l(arg uably,made it even morec onf using).

That  is  how J od a-T i me was  b o rn: t he great altern ative date /t i me  API for J a va.  T he Java  8’s Ne w Dat e -Time A PI (JSR 3 10) was h ea vily i nfl uenced byJoda-Tim e and too k  theb es t ofit.  The n ew  ja va.ti me pac k age  cont ains a ll  the c lasse sfor date , time, date/time, time  zones , ins tan ts, durat ion ,  an d clocksmani pulation.Inthe  desi gno f the  API th e i m mutab ilit y  has been ta ken i nt o account v e r y  se rious ly: no cha ngeallowed (the toug h  lesson learnt  fro m jav a.u t il.C al endar). If the  mo di f i cation i srequired, t he new i ns t anceof res pectiv e
asLongStream().mapToDouble( points_-> points_/ totalPoints ).boxed().mapToLong( weigth_-> (_long_)( weigth_*_100 ) ).mapToObj(_percentage -> percentage_+ "%" ).collect( Collectors.toList()_); System.out.println( result_);

The_console output is just here:

1 [ 19 %, 50 %, 30 %]

And lastly, as_we_mentioned before,_the_Stream_API is not only about_Java collections. The typical I/O_operations like_reading the text file line by line is_a_very good candidate_to benefit from stream processing. Here is a small_example to confirm that.

1 2 3_4 final Path_path_=_new File( filename ).toPath();_try ( Stream< String > lines_= Files.lines( path, StandardCharsets.UTF_8 ) )_{ lines.onClose( () -> System.out.println( "Done!" )_).forEach( System.out::println ); }

The onClose method_called on the stream returns_an equivalent_stream with an additional close_handler. Close handlers_are run_when the close()_method is called on the stream.

Stream_API together with_Lambdas and Method References baked by_Interface’s_Default and Static_Methods_is_the Java_8 response to_the_modern paradigms_in_software development. For more details, please_refer_to official documentation.

4.3. Date/Time API (JSR 310)

Java_8 makes one more_take_on date and time_management by delivering New Date-Time_API (JSR 310). Date and time_manipulation is_being one_of the worst pain points for Java developers. The standard java.util.Date_followed by java.util.Calendar hasn’t improved the_situation at all (arguably,_made it_even_more confusing).

That is_how_Joda-Time was_born: the great alternative date/time API for_Java. The_Java 8’s New Date-Time API (JSR_310) was heavily influenced_by_Joda-Time and took the best of_it. The new java.time package contains_all the classes for date,_time,_date/time,_time zones, instants, duration, and_clocks manipulation. In the design of_the API the_immutability has been taken into account very_seriously:_no change allowed (the tough lesson_learnt_from java.util.Calendar). If the modification is_required,_the_new instance of respective