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getUrlEncoder() METHOD of Base64 class RETURNS a Base64.Encoder that encodes USING the URL and Filename safe TYPE base64 encoding SCHEME.

getUrlEncoder() method of Base64 class returns a Base64.Encoder that encodes using the URL and Filename safe type base64 encoding scheme.

getUrlDecoder() method of BASE64 CLASS RETURNS a Base64.Decoder that DECODES using the URL and Filename safe type base64 encoding scheme.

getUrlDecoder() method of Base64 class returns a Base64.Decoder that decodes using the URL and Filename safe type base64 encoding scheme.

getMimeEncoder() METHOD of BASE64 class returns a Base64.Encoder that encodes USING the MIME TYPE base64 encoding scheme.

getMimeEncoder() method of Base64 class returns a Base64.Encoder that encodes using the MIME type base64 encoding scheme.

getMimeDecoder() METHOD of BASE64 CLASS returns a Base64.Decoder that DECODES USING the MIME type base64 decoding scheme.

getMimeDecoder() method of Base64 class returns a Base64.Decoder that decodes using the MIME type base64 decoding scheme.

getEncoder() METHOD of Base64 class returns a Base64.Encoder that encodes USING the Basic TYPE base64 encoding scheme.

getEncoder() method of Base64 class returns a Base64.Encoder that encodes using the Basic type base64 encoding scheme.

getDecoder() method of BASE64 class returns a Base64.Decoder that decodes using the Basic type base64 ENCODING SCHEME.

getDecoder() method of Base64 class returns a Base64.Decoder that decodes using the Basic type base64 encoding scheme.

STATIC CLASS Base64.Encoder − This class IMPLEMENTS an encoder for encoding byte data using the Base64 encoding scheme as SPECIFIED in RFC 4648 and RFC 2045.

static class Base64.Encoder − This class implements an encoder for encoding byte data using the Base64 encoding scheme as specified in RFC 4648 and RFC 2045.

STATIC class Base64.Decoder − This class IMPLEMENTS a decoder for DECODING byte data USING the Base64 encoding scheme as specified in RFC 4648 and RFC 2045.

static class Base64.Decoder − This class implements a decoder for decoding byte data using the Base64 encoding scheme as specified in RFC 4648 and RFC 2045.

Following CODE gets the INSTANT of ZONED date time using time in of MILLISECONDS −

Instant now = currentDate.toInstant();
ZoneId currentZone = ZoneId.systemDefault();
ZonedDateTime zonedDateTime = ZonedDateTime.ofInstant(now, currentZone);
System.out.println("Zoned date: " + zonedDateTime);

Following code gets the instant of zoned date time using time in of milliseconds −

Instant now = currentDate.toInstant();
ZoneId currentZone = ZoneId.systemDefault();
ZonedDateTime zonedDateTime = ZonedDateTime.ofInstant(now, currentZone);
System.out.println("Zoned date: " + zonedDateTime);

Following code gets the INSTANT of local DATE time USING time in of MILLISECONDS −

Instant now = currentDate.toInstant();
ZoneId currentZone = ZoneId.systemDefault();
LocalDateTime localDateTime = LocalDateTime.ofInstant(now, currentZone);
System.out.println("Local date: " + localDateTime);

Following code gets the instant of local date time using time in of milliseconds −

Instant now = currentDate.toInstant();
ZoneId currentZone = ZoneId.systemDefault();
LocalDateTime localDateTime = LocalDateTime.ofInstant(now, currentZone);
System.out.println("Local date: " + localDateTime);

FOLLOWING code gets the INSTANT of current DATE in terms of MILLISECONDS −

//GET the instant of current date in terms of milliseconds

Instant now = currentDate.toInstant();

Following code gets the instant of current date in terms of milliseconds −

//Get the instant of current date in terms of milliseconds

Instant now = currentDate.toInstant();

Following CODE gets second SATURDAY of next month USING java8 −

//get the second saturday of next month

LocalDate firstInYear = LocalDate.of(date1.getYear(),date1.getMonth(), 1);

LocalDate secondSaturday = firstInYear.with(TemporalAdjusters.nextOrSame(DayOfWeek.SATURDAY)).with(TemporalAdjusters.next(DayOfWeek.SATURDAY));

System.out.println("Second Saturday on : " + secondSaturday);

Following code gets second saturday of next month using java8 −

//get the second saturday of next month

LocalDate firstInYear = LocalDate.of(date1.getYear(),date1.getMonth(), 1);

LocalDate secondSaturday = firstInYear.with(TemporalAdjusters.nextOrSame(DayOfWeek.SATURDAY)).with(TemporalAdjusters.next(DayOfWeek.SATURDAY));

System.out.println("Second Saturday on : " + secondSaturday);

FOLLOWING CODE gets NEXT tuesday using JAVA8 −

//get the next tuesday
LocalDate today = LocalDate.now();
LocalDate nextTuesday = today.with(TemporalAdjusters.next(DayOfWeek.TUESDAY));
System.out.println("Next Tuesday on : " + nextTuesday);

Following code gets next tuesday using java8 −

//get the next tuesday
LocalDate today = LocalDate.now();
LocalDate nextTuesday = today.with(TemporalAdjusters.next(DayOfWeek.TUESDAY));
System.out.println("Next Tuesday on : " + nextTuesday);

Following CODE adds 10 years to current date USING local datetime api −

//ADD 10 years to the current date
LocalDate today = LocalDate.now();
LocalDate nextDecade = today.plus(1, ChronoUnit.DECADES);
System.out.println("Date after ten year: " + nextDecade);

Following code adds 10 years to current date using local datetime api −

//add 10 years to the current date
LocalDate today = LocalDate.now();
LocalDate nextDecade = today.plus(1, ChronoUnit.DECADES);
System.out.println("Date after ten year: " + nextDecade);

Following code ADDS 1 year to current date USING local datetime api −

//ADD 1 year to the current date
LocalDate today = LocalDate.now();
LocalDate nextYear = today.plus(1, ChronoUnit.YEARS);
System.out.println("NEXT year: " + nextYear);

Following code adds 1 year to current date using local datetime api −

//add 1 year to the current date
LocalDate today = LocalDate.now();
LocalDate nextYear = today.plus(1, ChronoUnit.YEARS);
System.out.println("Next year: " + nextYear);

FOLLOWING code ADDS 1 month to current date USING local datetime api:

//add 1 month to the current date
LocalDate today = LocalDate.now();
LocalDate nextMonth = today.plus(1, ChronoUnit.MONTHS);
System.out.println("Next month: " + nextMonth);

Following code adds 1 month to current date using local datetime api:

//add 1 month to the current date
LocalDate today = LocalDate.now();
LocalDate nextMonth = today.plus(1, ChronoUnit.MONTHS);
System.out.println("Next month: " + nextMonth);

Following CODE ADDS 1 week to current DATE USING local datetime api −

//ADD 1 week to the current date
LocalDate today = LocalDate.now();
LocalDate nextWeek = today.plus(1, ChronoUnit.WEEKS);
System.out.println("Next week: " + nextWeek);

Following code adds 1 week to current date using local datetime api −

//add 1 week to the current date
LocalDate today = LocalDate.now();
LocalDate nextWeek = today.plus(1, ChronoUnit.WEEKS);
System.out.println("Next week: " + nextWeek);

Following CODE GETS the current date USING local datetime API −

//Get the current date
LocalDate today = LocalDate.now();
System.out.println("Current date: " + today);

Following code gets the current date using local datetime api −

//Get the current date
LocalDate today = LocalDate.now();
System.out.println("Current date: " + today);

JAVA.time.temporal.ChronoUnit enum is added in Java 8 to replace the INTEGER VALUES USED in old API to represent DAY, month, etc.

java.time.temporal.ChronoUnit enum is added in Java 8 to replace the integer values used in old API to represent day, month, etc.

ZONED − SPECIALIZED date-time API to DEAL with VARIOUS timezones.

Zoned − Specialized date-time API to deal with various timezones.

LOCAL − SIMPLIFIED date-time API with no COMPLEXITY of TIMEZONE handling.

Local − Simplified date-time API with no complexity of timezone handling.

YES! Using ScriptEngineManager, JAVASCRIPT CODE can be CALLED and interpreted in Java.

Yes! Using ScriptEngineManager, JavaScript code can be called and interpreted in Java.

For NASHORN engine, JAVA 8 introduces a new command line TOOL, jjs, to execute JAVASCRIPT CODES at console.

For Nashorn engine, JAVA 8 introduces a new command line tool, jjs, to execute javascript codes at console.

With Java 8, Nashorn, a much IMPROVED javascript engine is INTRODUCED, to replace the existing Rhino. Nashorn provides 2 to 10 TIMES better performance, as it directly compiles the code in memory and passes the bytecode to JVM. Nashorn uses invokedynamics feature, introduced in Java 7 to improve performance.

With Java 8, Nashorn, a much improved javascript engine is introduced, to replace the existing Rhino. Nashorn provides 2 to 10 times better performance, as it directly compiles the code in memory and passes the bytecode to JVM. Nashorn uses invokedynamics feature, introduced in Java 7 to improve performance.

Optional is a container OBJECT which is used to contain not-null objects. Optional object is used to represent null with ABSENT value. This class has various UTILITY methods to facilitate code to handle values as 'available' or 'not available' instead of checking null values. It is INTRODUCED in JAVA 8 and is similar to what Optional is in Guava.

Optional is a container object which is used to contain not-null objects. Optional object is used to represent null with absent value. This class has various utility methods to facilitate code to handle values as 'available' or 'not available' instead of checking null values. It is introduced in Java 8 and is similar to what Optional is in Guava.

Following CODE will PRINT the average of all numbers present in a list.

List numbers = Arrays.asList(3, 2, 2, 3, 7, 3, 5);
IntSummaryStatistics STATS = integers.stream().mapToInt((X) −> x).summaryStatistics();
System.out.println("Average of all numbers : " + stats.getAverage());

Following code will print the average of all numbers present in a list.

List numbers = Arrays.asList(3, 2, 2, 3, 7, 3, 5);
IntSummaryStatistics stats = integers.stream().mapToInt((x) −> x).summaryStatistics();
System.out.println("Average of all numbers : " + stats.getAverage());

Following CODE will print the SUM of all numbers present in a list.

List numbers = Arrays.asList(3, 2, 2, 3, 7, 3, 5);
IntSummaryStatistics stats = integers.stream().mapToInt((X) −> x).summaryStatistics();
System.out.println("Sum of all numbers : " + stats.getSum());

Following code will print the sum of all numbers present in a list.

List numbers = Arrays.asList(3, 2, 2, 3, 7, 3, 5);
IntSummaryStatistics stats = integers.stream().mapToInt((x) −> x).summaryStatistics();
System.out.println("Sum of all numbers : " + stats.getSum());

Following code will PRINT the highest NUMBER present in a list.

List NUMBERS = Arrays.asList(3, 2, 2, 3, 7, 3, 5);
IntSummaryStatistics stats = integers.stream().mapToInt((X) −> x).summaryStatistics();
System.out.println("Lowest number in List : " + stats.getMin());

Following code will print the highest number present in a list.

List numbers = Arrays.asList(3, 2, 2, 3, 7, 3, 5);
IntSummaryStatistics stats = integers.stream().mapToInt((x) −> x).summaryStatistics();
System.out.println("Lowest number in List : " + stats.getMin());

Following code will print the highest number PRESENT in a LIST.

List numbers = Arrays.asList(3, 2, 2, 3, 7, 3, 5);
IntSummaryStatistics STATS = integers.stream().mapToInt((x) −> x).summaryStatistics();
System.out.println("Highest number in List : " + stats.getMax());

Following code will print the highest number present in a list.

List numbers = Arrays.asList(3, 2, 2, 3, 7, 3, 5);
IntSummaryStatistics stats = integers.stream().mapToInt((x) −> x).summaryStatistics();
System.out.println("Highest number in List : " + stats.getMax());

With Java 8, STATISTICS COLLECTORS are introduced to calculate all statistics when STREAM PROCESSING is being done.

With Java 8, statistics collectors are introduced to calculate all statistics when stream processing is being done.

COLLECTORS are used to COMBINE the result of processing on the elements of a stream. Collectors can be used to return a list or a string.

List<String>strings = Arrays.asList("ABC", "", "bc", "efg", "ABCD","", "JKL");
List<String> filtered = strings.stream().filter(string -> !string.isEmpty()).collect(Collectors.toList());
System.out.println("Filtered List: " + filtered);
String mergedString = strings.stream().filter(string -> !string.isEmpty()).collect(Collectors.joining(", "));
System.out.println("Merged String: " + mergedString);

Collectors are used to combine the result of processing on the elements of a stream. Collectors can be used to return a list or a string.

List<String>strings = Arrays.asList("abc", "", "bc", "efg", "abcd","", "jkl");
List<String> filtered = strings.stream().filter(string -> !string.isEmpty()).collect(Collectors.toList());
System.out.println("Filtered List: " + filtered);
String mergedString = strings.stream().filter(string -> !string.isEmpty()).collect(Collectors.joining(", "));
System.out.println("Merged String: " + mergedString);

parallelStream is the alternative of STREAM for parallel processing. Take a look at the FOLLOWING CODE SEGMENT that prints a count of empty strings using parallelStream.

List<String> strings = Arrays.asList("abc", "", "bc", "efg", "abcd","", "jkl");
//get count of empty string
int count = strings.parallelStream().filter(string −> string.isEmpty()).count();
//It is very easy to SWITCH between sequential and parallel streams.

parallelStream is the alternative of stream for parallel processing. Take a look at the following code segment that prints a count of empty strings using parallelStream.

List<String> strings = Arrays.asList("abc", "", "bc", "efg", "abcd","", "jkl");
//get count of empty string
int count = strings.parallelStream().filter(string −> string.isEmpty()).count();
//It is very easy to switch between sequential and parallel streams.

The following code segment SHOWS how to PRINT 10 random numbers in a SORTED order.

Random random = NEW Random();
random.ints().limit(10).sorted().forEach(System.out::PRINTLN);

The following code segment shows how to print 10 random numbers in a sorted order.

Random random = new Random();
random.ints().limit(10).sorted().forEach(System.out::println);

The 'sorted' METHOD is USED to SORT the STREAM.

The 'sorted' method is used to sort the stream.

The FOLLOWING code segment shows how to print 10 RANDOM NUMBERS.

Random random = new Random();
random.ints().LIMIT(10).forEach(System.out::println);

The following code segment shows how to print 10 random numbers.

Random random = new Random();
random.ints().limit(10).forEach(System.out::println);

The 'limit' METHOD is USED to REDUCE the SIZE of the STREAM.

The 'limit' method is used to reduce the size of the stream.

The following CODE segment prints a count of empty STRINGS using filter.

LIST<STRING>strings = Arrays.asList("abc", "", "bc", "efg", "abcd","", "jkl");
//GET count of empty string
int count = strings.stream().filter(string −> string.isEmpty()).count();

The following code segment prints a count of empty strings using filter.

List<String>strings = Arrays.asList("abc", "", "bc", "efg", "abcd","", "jkl");
//get count of empty string
int count = strings.stream().filter(string −> string.isEmpty()).count();

The 'filter' method is USED to ELIMINATE elements BASED on a criteria.

The 'filter' method is used to eliminate elements based on a criteria.

The following code segment prints UNIQUE SQUARES of numbers using map.

List<Integer&GT; numbers = Arrays.asList(3, 2, 2, 3, 7, 3, 5);

//get list of unique squares

List<Integer> squaresList = numbers.stream().map( i -> i*i).DISTINCT().collect(Collectors.toList());

The following code segment prints unique squares of numbers using map.

List<Integer> numbers = Arrays.asList(3, 2, 2, 3, 7, 3, 5);

//get list of unique squares

List<Integer> squaresList = numbers.stream().map( i -> i*i).distinct().collect(Collectors.toList());

The 'MAP' METHOD is used to map each element to its corresponding RESULT.

The 'map' method is used to map each element to its corresponding result.

The following code SEGMENT shows how to print 10 RANDOM numbers using FOREACH.

Random random = new Random();
random.ints().LIMIT(10).forEach(System.out::println);

The following code segment shows how to print 10 random numbers using forEach.

Random random = new Random();
random.ints().limit(10).forEach(System.out::println);

STREAM has provided a NEW method 'forEach' to ITERATE each ELEMENT of the stream.

Stream has provided a new method 'forEach' to iterate each element of the stream.

STREAM operations do the iterations internally over the source ELEMENTS provided, in contrast to COLLECTIONS where explicit ITERATION is required.

Stream operations do the iterations internally over the source elements provided, in contrast to Collections where explicit iteration is required.

Most of the stream operations return stream itself so that their result can be pipelined. These operations are called intermediate operations and their FUNCTION is to take input, process them, and return output to the target. collect() method is a terminal OPERATION which is normally present at the end of the PIPELINING operation to mark the end of the stream.

Most of the stream operations return stream itself so that their result can be pipelined. These operations are called intermediate operations and their function is to take input, process them, and return output to the target. collect() method is a terminal operation which is normally present at the end of the pipelining operation to mark the end of the stream.

Stream represents a SEQUENCE of OBJECTS from a source, which SUPPORTS aggregate OPERATIONS.

Stream represents a sequence of objects from a source, which supports aggregate operations.

USING NAME of the INTERFACE.

interface Vehicle {
static void blowHorn(){
System.out.println("Blowing horn!!!");
}
}
class CAR implements Vehicle {
public void PRINT(){
Vehicle.blowHorn();
}
}

Using name of the interface.

interface Vehicle {
static void blowHorn(){
System.out.println("Blowing horn!!!");
}
}
class Car implements Vehicle {
public void print(){
Vehicle.blowHorn();
}
}

Using super keyword ALONG with INTERFACE NAME.

interface VEHICLE {
default void print(){
System.out.println("I am a vehicle!");
}
}
CLASS Car implements Vehicle {
public void print(){
Vehicle.super.print();
}
}

Using super keyword along with interface name.

interface Vehicle {
default void print(){
System.out.println("I am a vehicle!");
}
}
class Car implements Vehicle {
public void print(){
Vehicle.super.print();
}
}

An interface can also have static HELPER methods from JAVA 8 onwards.

PUBLIC interface vehicle {
default VOID print(){
System.out.println("I am a vehicle!");
}
static void blowHorn(){
System.out.println("Blowing HORN!!!");
}
}

An interface can also have static helper methods from Java 8 onwards.

public interface vehicle {
default void print(){
System.out.println("I am a vehicle!");
}
static void blowHorn(){
System.out.println("Blowing horn!!!");
}
}

With java 8, an INTERFACE can have default IMPLEMENTATION of a FUNCTION in INTERFACES.

With java 8, an interface can have default implementation of a function in interfaces.

It represents an operation on a SINGLE operand that PRODUCES a RESULT of the same TYPE as its operand.

It represents an operation on a single operand that produces a result of the same type as its operand.