Java Data Type Q&A Questions and Answers





bigdecimal /

alternative 1ArithmeticException 1
bigdecimal 88c 1
convert 7currency 3
decimal 8digit 2
divide 7double 16
Encoding 2equal 1
exception 2Financial 2
float 4format 3
logarithm 1Long 4
math 12MathContext 2
memory 1money 3
optimization 2parse 4
power 2precision 5
Root 2round 37
scale 5scientific 3
String 15stripTrailingZeroes 2
trail 4trim 3
valueof 3zero 4

biginteger /

BigDecimal 7biginteger 88
bit 2byte 5
convert 3cryptography 3
digit 4encrypt 1
format 3long 1
math 6overflow 3
pow 4power 4
prime 4random 5
root 3sign 2
square 1String 7
toByteArray 3valueOf 3

bit /

128 bit 316 bit 8
24 bit 232 Bit 21
64 bit 1 10064 bit 2 8
64 bit JVM 2064 bit OS 1
AES 7ascii 3
binary 14bit 1 100
bit 2 50bitwise 42
bufferedimage 7c 5
character 6Convert 15
cryptography 9encrypt 2
enum 4exception 1
hex 9image 7
long 13manipulation 7
mask 5math 3
memory 6Negative Number 5
operation 19operator 46
Pattern 5pixel 4
Primitive 6shift 32
sign 2size 6
tiff 4ZipException 1

Boolean /

assignment 3autobox 5
beanutils 1bit 8
bitwise 5Boolean 1 100
Boolean 2 90Cast 4
Char 3condition 9
convert 13equal 9
error 11exception 5
expression 30false 12
getBoolean 4inverse 3
JavaBean 5logic 7
loop 11memory 6
method 39object 9
operator 11parameter 5
reflection 1return 30
size 11statement 18
switch 4true 9
value 27variable 19
volatile 1wrapper 1

byte /

audio 2binary 8
bit 37bitwise 7
buffer 8BufferedImage 5
byte 1 100byte 2 100
byte 3 59bytearray 9
bytecode 4Cast 9
character 19compare 7
convert 1 100convert 2 28
decrypt 3encoding 11
encrypt 5filewriter 3
hex 19image 14
jni 5jprofiler 1
JVM 3limit 4
Literal 6long 8
memory 6offset 2
order 2OutOfMemoryError 3
parse 5random 3
range 4read 27
sequence 6short 11
sign 14size 11
split 3stream 2
unicode 8utf8 5
wrapper 3

Calendar /

add 21before 8
Calendar 1 100Calendar 2 100
Calendar 3 85compare 16
convert 27date 1 100
date 2 12day 21
DST 12getInstance 11
getTime 11Gregorian 1
GregorianCalendar 18locale 7
Month 34schedule 4
String 26time 36
timezone 29util 39
week 40year 19

cast /

autobox 1Automatic 7
c 5cast 1 100
cast 2 35child 2
Class 36compiler 6
convert 15DefaultListModel 3
Downcast 5Dynamic 18
entity 2error 15
Exception 54Explicit 6
extend 2graphics 1
graphics2d 3gson 1
implicit 1instanceof 2
jni 5jruby 4
jvm 5List 10
long 5memory 1
method 8null 4
object 64oop 4
operation 1operator 6
parse 5precision 1
primitive 12problem 30
question 22reflection 10
runtime 13safe 4
sign 1statement 4
type 61unchecked 10
variable 20warn 7

character /

Arabic 9ascii 17
Backspace 3binary 12
bit 7bufferedreader 1
byte 9C 5
carriage 4char 1 100
char 2 100char 3 23
character 1 100character 2 100
character 3 100character 4 100
character 5 46charset 4
check 59Chinese 15
compare 49console 1
convert 1 100convert 2 79
count 44DecimalFormat 1
decode 13display 46
Encode 10encoding 61
encrypt 4english 4
equal 6escape 50
Font 9Format 11
French 5Generator 2
hex 6html 11
Illegal 16image 4
input 38intellij 1
internationalization 10invalid 3
isLetter 4japanese 24
jni 7json 6
letter 8literal 14
loop 15multibyte 7
newline 17number 34
operator 7parse 18
password 8Pattern 10
pdf 10primitive 7
print 46random 23
read 57Recognition 6
remove 79replace 1 100
replace 2 2resourcebundle 3
scanner 8search 12
size 9slash 5
space 19Spanish 4
special 68split 28
stream 1Tab 6
text 10Type 26
unicode 49utf 4
utf8 2value 33
variable 7whitespace 4
Wildcard 3word 12
write 15

Date Time /

add 64calculate 62
calculation 18calender 11
compare 1 100compare 2 26
Convert 1 100Convert 2 89
current 53date 1 100
date 2 100date 3 100
date 4 100date 5 100
date 6 100date 7 100
date 8 100date 9 43
datetime 1 100datetime 2 6
DAY 94Daylight 11
difference 48dst 10
excel 11find 25
Format 1 100Format 2 100
Format 3 100Format 4 100
Format 5 79GMT 19
Gregorian 2hour 24
jodatime 75list 14
locale 33milliseconds 32
month 54parse 1 100
parse 2 28query 10
range 21schedule 7
Sort 10String 73
time 1 100time 2 31
timestamp 1 100timestamp 2 20
type 23Unparseable 24
UTC 23validation 63
WEEK 47YEAR 54

Date Time Format /

capitalize 1convert 6
Date Time Format 30date 6
datetime 1day 3
Excel 2format 14
jodatime 2locale 4
localization 2month 2
parse 8ParseException 2
Pattern 4strftime 1
String 7Text 3
time 3timezone 6
year 2

decimal /

Ascii 7binary 17
bit 4byte 2
character 2comma 5
convert 1 100convert 2 4
currency 2decimal 81
DecimalFormat 2decode 2
digit 15divide 5
double 10expansion 2
exponential 1float 8
format 70fraction 6
hex 2hexadecimal 2
length 1locale 4
long 1math 3
numberformat 2octal 4
output 4place 85
point 17precision 6
restrict 2round 25
scientific 3separator 5
string 10Trim 3
value 14

Development /

base64 66equal 1 100
equal 2 2Exception 1 100
Exception 2 20format 1 100
format 2 100format 3 10
getResourceAsStream 7ImageIO 5
initialization 18json 47
math 31validation 48

double /

add 18buffer 36
byte 7calculation 14
cast 10character 5
compare 20convert 71
divide 8Format 42
long 21math 17
money 4number 31
parse 28parseDouble 18
precision 30round 37
subtraction 7value 1
variable 29

enum /

Annotation 10c 6
class 39Compare 11
compile 6Convert 11
declare 11element 14
enum 1 100enum 2 100
enum 3 100enum 4 12
enumeration 19EnumSet 6
equal 2error 18
extend 14field 8
function 8instance 8
keyword 7loop 5
member 5method 28
nest 11number 7
object 10ordinal 7
package 5Parameter 8
parse 2Pattern 9
problem 30Property 6
reference 11reflection 9
scjp 2singleton 9
Statement 13Switch 15
type 31Usage 6
value 38valueOf 9
variable 10

float /

accuracy 5arithmetic 5
audio 2binary 4
byte 4c 1
Cast 10clojure 1
compare 9convert 67
currency 3decimalformat 1
divide 7double 47
error 15exception 2
float 1 100float 2 21
floatToIntBits 3format 16
ieee754 4image 3
jni 1literal 2
long 8math 7
NAN 3number 30
operator 2parseFloat 4
precision 17primitive 9
printf 2Random 4
round 11swt 1
union 1value 27
variable 10

hexadecimal /

ascii 18Base64 2
binary 9Color 6
convert 35Decode 4
encoding 3Escape 1
format 6hex 48
hexadecimal 27RGB 2
syntax 1Unicode 6
value 23

Integer /

autobox 15bigdecimal 12
BigInteger 15binary 23
bit 27bitwise 15
boolean 26byte 59
Cast 49char 67
character 27compare 43
console 7convert 1 100
convert 2 53cryptography 2
decimal 17digit 21
divide 13double 74
element 9enum 17
equal 22error 20
float 45format 27
hex 21input 18
Integer 1 100Integer 2 100
Integer 3 100Integer 4 100
Integer 5 85length 13
literal 15Long 54
loop 21math 19
memory 7negative 16
number 93odd 6
operator 19output 14
overflow 12parameter 15
parse 40parseint 35
primitive 19println 6
public 6random 28
range 13reverse 12
Round 16Scanner 13
short 21sign 27
size 8Sort 13
split 12string 1 100
string 2 78sum 22
swap 4too large 10
unique 7validation 12
value 90valueOf 14
variable 36wrapper 5
zero 16

Number /

Big number 12binary 24
calculate 33Convert 66
Count number 67factorial number 6
game 24input number 44
Large Number 28line number 52
long 30loop 34
magic 11maximum 15
negative Number 40octal 4
Page Number 25phone number 25
prime number 86Random Number 1 100
Random Number 2 100Random Number 3 100
Random Number 4 18Random 43
read 31revision 1
sequence 20Serial Number 18
small 23Sort 23
sum 29text 16
unique Number 32variable 28
version number 15

Number Format /

comma 2Convert 7
country 2currency 5
digit 8local 1
locale 2localization 1
money 1Notation 2
number format 1 100number format 2 22
numberformat 54NumberFormatException 1 100
NumberFormatException 2 9numeric 3
Pattern 5phone 4
Scientific 2sign 3
validation 4

primitive /

anonymous 3autobox 7
boxing 3c 1
Check 6convert 7
equal 3field 1
immutable 4instanceof 2
memory 3null 5
Parameter 3primitive 1 100
primitive 2 27reference 10
reflection 11sign 3
swap 1value 15
variable 12wrapper 5

SimpleDateFormat /

convert 19date 22
dateformat 13datetime 12
day 12dd 1
Format 27GMT 4
locale 8month 13
parse 34pattern 8
PM 4SimpleDateFormat 94
ss 4string 15
time 9timezone 16

string /

append 21args 51
binary 31Buffer 51
c 20case 34
charAt 26check 1 100
check 2 10color 31
compare 1 100compare 2 89
comparision 24compile 16
concat 27concatenate 12
concatenation 24contain 67
convert 1 100convert 2 55
Count 40declare 26
decode 11decrypt 15
difference 41display 28
drawString 5empty 25
encode 9encoding 33
encrypt 24error 26
Escape 19expression 24
extract 45find 70
font 11html 50
image 10immutable 71
index 51indexOf 59
Insert 27intern 27
japanese 5jni 4
length 61letter 35
line 43List 57
Literal 63Long 51
loop 71manipulation 65
match 45memory 41
MessageFormat 9newline 10
null 59operator 24
order 21padding 15
parse 1 100parse 2 29
pass 58Pattern 35
permutation 7Pool 39
print 45quote 33
read 39reflection 18
remove 75replace 1 100
replace 2 46replaceAll 64
replaceFirst 10reverse 63
scanner 30search 63
sentence 13size 27
Sort 39space 83
Split 1 100Split 2 100
Split 3 100Split 4 25
stream 1String 1 100
String 10 100String 11 100
String 12 100String 13 100
String 14 100String 15 100
String 16 100String 17 100
String 18 100String 19 100
String 2 100String 20 100
String 21 17String 3 100
String 4 100String 5 100
String 6 100String 7 100
String 8 100String 9 100
StringIndexOutOfBoundsException 3switch 26
text 33trim 21
unicode 49utf 2
value 1 100value 2 14
valueOf 10variable 65
whitespace 9word 60

StringBuffer /

append 18capacity 4
compare 4concatenation 2
content 2convert 4
deleteCharAt 1efficiency 1
end 2final 2
instance 1length 1
memory 6new 4
OutOfMemoryError 2parse 4
replace 6setCharAt 1
size 7start 1
StringBuffer 1 100StringBuffer 2 95
stringwriter 1text 3

StringBuilder /

append 5capacity 2
compare 2concatenation 5
content 1efficiency 1
final 1memory 3
OutOfMemoryError 1replace 8
StringBuilder 58

StringTokenizer /

delimiter 9ERROR 6
line 3nextToken 3
null 4read 2
Scanner 3Sort 3
split 17StringTokenizer 1 100
StringTokenizer 2 100StringTokenizer 3 17
token 13word 4

substring /

endIndex 1error 2
extract 8find 15
index 4IndexOf 5
match 6memory 2
range 5Replace 16
search 12split 6
substring 1 100substring 2 53
word 3

TimeZone /

convert 60country 2
date 39datetime 8
daylight savings 6default 4
dst 13EST 5
format 12getDefault 5
getTimeZone 1gmt 7
GregorianCalendar 4hour 7
Joda 2jodatime 9
locale 10parse 12
PST 4system 5
Time 16timestamp 5
TimeZone 1 100TimeZone 2 2
UTC 5