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Java References
Java String Methods
Splits the string at the specified string (regex)
Compares two strings in the dictionary order
Compares two strings ignoring case differences
Returns the length of the string
Replace all matching characters/text in the string
Replace all substrings matching the regex pattern
Returns a substring from the given string
Compares two strings
Compares two strings ignoring case differences
Checks whether the string contains a substring
Returns the index of the character/substring
Removes any leading and trailing whitespace
Returns the character at the given index
Converts characters in the string to lower case
Concatenates two strings and returns it
Returns the string representation of a value
checks whether the string matches the given regex
Checks if the string begins with the given string
Checks if the string ends with the given string
Checks whether a string is empty or not
Returns a canonical representation of the string
Encodes the string into a sequences of bytes
Checks whether the string is equal to charSequence
Returns a hash code for the string
Joins the given strings using the delimiter
Replace the first matching substring
Returns a subsequence from the string
Converts the string to a char array
Returns a formatted string
Java ArrayList Methods
inserts the element to the arraylist
adds all elements of a collection to arraylist
removes all the elements from arraylist
makes a copy of the array list
checks if the element is present in the arraylist
returns the element present in the specified index
returns the position of the specified element
removes multiple elements from the arraylist
removes the single element from the arraylist
returns the length of an arraylist
checks if the arraylist is empty
returns a portion of the arraylist
replace the single element from an arraylist
sorts the arraylist according to specified order
converts an arraylist to an array
converts the arraylist into a String
set the size of an araylist
returns position of last occurrence of the element
retains only the common elements
checks if a collection is a subset of arraylist
trims the capacity of arraylist equal to the size
removes a portion of the arraylist
replace all elements from the arraylist
removes element that satisfy the condition
performs an action to all elements of arraylist
returns an iterate to loop through the ArrayList
Java HashMap Methods
remove all elements from HashMap
makes the copy of the hashmap
checks if the HashMap is empty
returns the number of items in HashMap
inserts the specified item to the hashmap
inserts all items from a map to HashMap
inserts item if the key is not already present
removes the mapping for the specified key
checks if the specified key is present in HashMap
checks if HashMap contains the specified value
replaces the value for the specified key
replaces all values with
returns the value using the specified key
returns specified default value if key not found
performs the action to all entries of HashMap
returns a set view of all entries
returns a set view of all the keys of HashMap
returns a view of all values present in HashMap
merges the specified mapping to the HashMaps
computes a new value for the specified key
computes value if mapping for key is not present
computes a value for the mapping if key is present
Java Math Methods
returns the absolute value of a number
returns the arc cosine of the specified value
adds the specified numbers and returns it
returns the arc sine of the specified argument
returns the inverse tangent function of a value
returns the cosine of the specified angle
returns the sine of the specified angle in radians
returns the tangent value of the specified angle
returns the hyperbolic sine of the specified value
returns hyperbolic cosine of the specified value
returns hyperbolic tangent of the specified value
returns the square root of the specified number
returns the cube root of the specified number
returns first argument raised to power of second
subtracts the specified numbers and returns it
multiplies the specified numbers and returns it
adds 1 to the specified number and returns it
subtracts 1 from specified number and returns it
negates the specified variable and returns it
returns the int value from specified long argument
returns the smaller value among the arguments
returns the maximum value among the arguments
rounds the specified value upward
rounds the specified value downward and returns it
rounds the specified argument and returns it
converts angle from degree to radians
converts angle from radians to degrees
returns θ converting coordinates (x, y) to (r, θ)
copies the sign of second argument to the first
returns e raised to power of given value
returns e raised to power of given value minus 1
returns the unbiased exponent of specified number
computes the hypotenuse of a right-angle triangle
returns the remainder as per the IEEE 754 standard
returns the natural logarithm of specified value
returns the base 10 logarithm of specified value
returns natural logarithm of (specified value + 1)
returns number adjacent to specified number
returns number greater than and adjacent to value
returns number less than and adjacent to the value
returns closest mathematical integer of the vaue
returns a random value between 0.0 and 1.0
Java Object Methods
returns the class name of the object
returns the hashcode value of the object
converts an object into the string
checks if two objects are equal
creates a copy of the object