Java by API/java.lang/Integer — различия между версиями
Admin (обсуждение | вклад) м (1 версия) |
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(нет различий)
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Версия 17:43, 31 мая 2010
Содержание
- 1 Integer: bitCount(int i)
- 2 Integer: equals(Object obj)
- 3 Integer: highestOneBit(int i)
- 4 Integer: Integer.SIZE
- 5 Integer: intValue()
- 6 Integer: lowestOneBit(int i)
- 7 Integer.MAX_VALUE
- 8 Integer: MIN_VALUE
- 9 Integer: numberOfLeadingZeros(int i)
- 10 Integer: numberOfTrailingZeros(int i)
- 11 Integer: parseInt(String stringValue)
- 12 Integer: reverseBytes(int i)
- 13 Integer: rotateLeft(int i, int distance)
- 14 Integer: signum(int i)
- 15 Integer: toBinaryString(int intValue)
- 16 Integer: toHexString(int intValue)
- 17 Integer: toOctalString(int intValue)
- 18 Integer: valueOf(String stringValue)
Integer: bitCount(int i)
import java.io.IOException;
public class MainClass {
public static void main(String args[]) throws IOException {
int n = 170; // 10101010
System.out.println("Value in binary: 10101010");
System.out.println("Number of one bits: " + Integer.bitCount(n));
System.out.println("Highest one bit: " + Integer.highestOneBit(n));
System.out.println("Lowest one bit: " + Integer.lowestOneBit(n));
System.out.println("Number of leading zeros : " + Integer.numberOfLeadingZeros(n));
System.out.println("Number of trailing zeros : " + Integer.numberOfTrailingZeros(n));
System.out.println("\nBeginning with the value 1, " + "rotate left 16 times.");
n = 1;
for (int i = 0; i < 16; i++) {
n = Integer.rotateLeft(n, 1);
System.out.println(n);
}
}
}
Integer: equals(Object obj)
/*
* Output:
true
*/
public class MainClass {
public static void main(String args[]) {
Integer iobj1 = new Integer(5);
Integer iobj2 = new Integer("5");
System.out.println(iobj1.equals(iobj2));
}
}
Integer: highestOneBit(int i)
import java.io.IOException;
public class MainClass {
public static void main(String args[]) throws IOException {
int n = 170; // 10101010
System.out.println("Value in binary: 10101010");
System.out.println("Number of one bits: " + Integer.bitCount(n));
System.out.println("Highest one bit: " + Integer.highestOneBit(n));
System.out.println("Lowest one bit: " + Integer.lowestOneBit(n));
System.out.println("Number of leading zeros : " + Integer.numberOfLeadingZeros(n));
System.out.println("Number of trailing zeros : " + Integer.numberOfTrailingZeros(n));
System.out.println("\nBeginning with the value 1, " + "rotate left 16 times.");
n = 1;
for (int i = 0; i < 16; i++) {
n = Integer.rotateLeft(n, 1);
System.out.println(n);
}
}
}
Integer: Integer.SIZE
public class Main {
public static void main(String[] arg) {
System.out.println(Integer.SIZE);
}
}
Integer: intValue()
/*
* Output:
i1 = 5
i2 = 6
*/
public class MainClass {
public static void main(String args[]) {
Integer iobj1 = new Integer(5);
Integer iobj2 = new Integer("6");
int i1 = iobj1.intValue();
int i2 = iobj2.intValue();
System.out.println("i1 = " + i1);
System.out.println("i2 = " + i2);
}
}
Integer: lowestOneBit(int i)
import java.io.IOException;
public class MainClass {
public static void main(String args[]) throws IOException {
int n = 170; // 10101010
System.out.println("Value in binary: 10101010");
System.out.println("Number of one bits: " + Integer.bitCount(n));
System.out.println("Highest one bit: " + Integer.highestOneBit(n));
System.out.println("Lowest one bit: " + Integer.lowestOneBit(n));
System.out.println("Number of leading zeros : " + Integer.numberOfLeadingZeros(n));
System.out.println("Number of trailing zeros : " + Integer.numberOfTrailingZeros(n));
System.out.println("\nBeginning with the value 1, " + "rotate left 16 times.");
n = 1;
for (int i = 0; i < 16; i++) {
n = Integer.rotateLeft(n, 1);
System.out.println(n);
}
}
}
Integer.MAX_VALUE
/*
i=32767
i=-32768
i=-32767
i=2147483647
i=-2147483648
i=-2147483647
*/
public class MainClass {
public static void main(String[] unused) {
do_shorts();
do_ints();
}
protected static void do_shorts() {
short i = Short.MAX_VALUE;
System.out.println("i=" + i++);
System.out.println("i=" + i++);
System.out.println("i=" + i++);
}
protected static void do_ints() {
int i = Integer.MAX_VALUE;
System.out.println("i=" + i++);
System.out.println("i=" + i++);
System.out.println("i=" + i++);
}
}
Integer: MIN_VALUE
public class Main {
public static void main(String[] arg) {
System.out.println(Integer.MAX_VALUE);
System.out.println(Integer.MIN_VALUE);
}
}
Integer: numberOfLeadingZeros(int i)
import java.io.IOException;
public class MainClass {
public static void main(String args[]) throws IOException {
int n = 170; // 10101010
System.out.println("Value in binary: 10101010");
System.out.println("Number of one bits: " + Integer.bitCount(n));
System.out.println("Highest one bit: " + Integer.highestOneBit(n));
System.out.println("Lowest one bit: " + Integer.lowestOneBit(n));
System.out.println("Number of leading zeros : " + Integer.numberOfLeadingZeros(n));
System.out.println("Number of trailing zeros : " + Integer.numberOfTrailingZeros(n));
System.out.println("\nBeginning with the value 1, " + "rotate left 16 times.");
n = 1;
for (int i = 0; i < 16; i++) {
n = Integer.rotateLeft(n, 1);
System.out.println(n);
}
}
}
Integer: numberOfTrailingZeros(int i)
import java.io.IOException;
public class MainClass {
public static void main(String args[]) throws IOException {
int n = 170; // 10101010
System.out.println("Value in binary: 10101010");
System.out.println("Number of one bits: " + Integer.bitCount(n));
System.out.println("Highest one bit: " + Integer.highestOneBit(n));
System.out.println("Lowest one bit: " + Integer.lowestOneBit(n));
System.out.println("Number of leading zeros : " + Integer.numberOfLeadingZeros(n));
System.out.println("Number of trailing zeros : " + Integer.numberOfTrailingZeros(n));
System.out.println("\nBeginning with the value 1, " + "rotate left 16 times.");
n = 1;
for (int i = 0; i < 16; i++) {
n = Integer.rotateLeft(n, 1);
System.out.println(n);
}
}
}
Integer: parseInt(String stringValue)
/*
* Output:
Sum is 8
*/
public class MainClass {
public static void main(String args[]) {
int i = Integer.parseInt("3");
int j = Integer.parseInt("5");
int sum = i + j;
System.out.print("Sum is " + sum);
}
}
Integer: reverseBytes(int i)
public class Main {
public static void main(String args[]) {
System.out.println(Integer.reverseBytes(10));
System.out.println(Integer.reverseBytes(-10));
System.out.println(Integer.reverseBytes(0));
}
}
Integer: rotateLeft(int i, int distance)
import java.io.IOException;
public class MainClass {
public static void main(String args[]) throws IOException {
int n = 170; // 10101010
System.out.println("Value in binary: 10101010");
System.out.println("Number of one bits: " + Integer.bitCount(n));
System.out.println("Highest one bit: " + Integer.highestOneBit(n));
System.out.println("Lowest one bit: " + Integer.lowestOneBit(n));
System.out.println("Number of leading zeros : " + Integer.numberOfLeadingZeros(n));
System.out.println("Number of trailing zeros : " + Integer.numberOfTrailingZeros(n));
System.out.println("\nBeginning with the value 1, " + "rotate left 16 times.");
n = 1;
for (int i = 0; i < 16; i++) {
n = Integer.rotateLeft(n, 1);
System.out.println(n);
}
}
}
Integer: signum(int i)
public class Main {
public static void main(String args[]) {
System.out.println(Integer.signum(10));
System.out.println(Integer.signum(-10));
System.out.println(Integer.signum(0));
}
}
Integer: toBinaryString(int intValue)
/*
* Output:
Binary is 1011
*/
public class MainClass {
public static void main(String args[]) {
int i = 11;
System.out.println("Binary is " + Integer.toBinaryString(i));
}
}
Integer: toHexString(int intValue)
/*
* Output:
Hex is b
*/
public class MainClass {
public static void main(String args[]) {
int i = 11;
System.out.println("Hex is " + Integer.toHexString(i));
}
}
Integer: toOctalString(int intValue)
/*
* Output:
Octal is 13
*/
public class MainClass {
public static void main(String args[]) {
int i = 11;
System.out.println("Octal is " +
Integer.toOctalString(i));
}
}
Integer: valueOf(String stringValue)
/*
* Output:
true
c
12
2
13245
12341234
11234.123
4.321324123412341E10
*/
public class MainClass {
public static void main(String args[]) {
Boolean bool = Boolean.valueOf("true");
Character c = new Character("c");
Byte b = Byte.valueOf("12");
Short s = Short.valueOf("2");
Integer i = Integer.valueOf("13245");
Long l = Long.valueOf("12341234");
Float f = Float.valueOf("11234.1234");
Double d = Double.valueOf("43213241234.123412341234");
System.out.println(bool);
System.out.println(c);
System.out.println(b);
System.out.println(s);
System.out.println(i);
System.out.println(l);
System.out.println(f);
System.out.println(d);
}
}