Integer class

The Integer class wraps a value of the primitive type int. Integer class provides several methods for converting an int to a String and a String to an int.

static int MAX_VALUE: Maximum value an int can have.
static int MIN_VALUE: Minimum value an int can have.
static int SIZE: The number of bits used to represent an int value.

Constructor Summary

Integer(int value): Creates an Integer object for the int value.
Integer(String s): Creates an Integer object for the int value indicated by the String parameter.

Return an integer value as byte, double, float, int, long and short

byte byteValue(): Returns this Integer as a byte.
double doubleValue(): Returns this Integer as a double.
float floatValue(): Returns this Integer as a float.
int intValue(): Returns this Integer as an int.
long longValue(): Returns this Integer as a long.
short shortValue(): Returns this Integer as a short.

Compare two integer values

int compareTo(Integer anotherInteger): Compares two Integer objects numerically.
boolean equals(Object obj): Compares this object to the specified object.

Decode a string and return an integer value

static Integer decode(String nm): Decodes a String into an Integer.

Convert string to integer

static int parseInt(String s): Parses the string argument as a signed decimal integer.
static int parseInt(String s, int radix): Parses the string argument in the radix.
static Integer valueOf(int i): Returns a Integer instance representing the int value.
static Integer valueOf(String s): Returns an Integer holding the value of the String.
static Integer valueOf(String s, int radix): Returns an Integer from String based on the radix.

Convert integer to string

String toString(): Returns a String object representing this Integer's value.
static String toString(int i): Returns a String object representing the specified integer.
static String toString(int i, int radix): Returns a string representation of i in radix.

Reverse and rotate the integer in binary format

static int reverse(int i): Reversing the bits.
static int reverseBytes(int i): Reversing the bytes.
static int rotateLeft(int i, int distance): Rotating the bits by distance.
static int rotateRight(int i, int distance): Rotating the bits by distance.

Bit oriented operation

static int bitCount(int i): Count bits in the binary representation of the specified int value.
static int highestOneBit(int i): Returns an int value with at most a single one-bit, in the position of the highest-order ("leftmost") one-bit.
static int lowestOneBit(int i): Returns an int value with at most a single one-bit, in the position of the lowest-order ("rightmost") one-bit.

Return system property as integer

static Integer getInteger(String nm): Get the system property.
static Integer getInteger(String nm, int val): Get the integer value of the system property with a default value.
static Integer getInteger(String nm, Integer val): Returns the integer value of the system property with a default value.

Get the leading and trailing zeros

static int numberOfLeadingZeros(int i): Returns the number of zero bits preceding the highest-order ("leftmost") one-bit.
static int numberOfTrailingZeros(int i): Returns the number of zero bits following the lowest-order ("rightmost") one-bit.

Get the sign

static int signum(int i): Returns the sign.

Convert integer to binary, hexdecimal and octal format

static String toBinaryString(int i): Return the binary string for i.
static String toHexString(int i): Returns a hes string for i.
static String toOctalString(int i): Returns a octal string for i.

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