Java by API/java.lang/Double — различия между версиями

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Версия 17:43, 31 мая 2010

Double: byteValue()

  
public class Main {
  public static void main(String[] args) {
    Double dObj = new Double("10.50");
    byte b = dObj.byteValue();
    System.out.println(b);
    short s = dObj.shortValue();
    System.out.println(s);
    int i = dObj.intValue();
    System.out.println(i);
    float f = dObj.floatValue();
    System.out.println(f);
    double d = dObj.doubleValue();
    System.out.println(d);
  }
}
/*
10
10
10
10.5
10.5
*/





Double: compare(double d1, double d2)

  

public class Main {
  public static void main(String[] args) {
    double d1 = 5.5;
    double d2 = 5.4;
    int i1 = Double.rupare(d1, d2);
    if (i1 > 0) {
      System.out.println(">");
    } else if (i1 < 0) {
      System.out.println("<");
    } else {
      System.out.println("=");
    }
    Double dObj1 = new Double("5.5");
    Double dObj2 = new Double("5.4");
    int i2 = dObj1.rupareTo(dObj2);
    if (i2 > 0) {
      System.out.println(">");
    } else if (i2 < 0) {
      System.out.println("<");
    } else {
      System.out.println("=");
    }
  }
}





Double: compareTo(Double anotherDouble)

  

public class Main {
  public static void main(String[] args) {
    double d1 = 5.5;
    double d2 = 5.4;
    int i1 = Double.rupare(d1, d2);
    if (i1 > 0) {
      System.out.println(">");
    } else if (i1 < 0) {
      System.out.println("<");
    } else {
      System.out.println("=");
    }
    Double dObj1 = new Double("5.5");
    Double dObj2 = new Double("5.4");
    int i2 = dObj1.rupareTo(dObj2);
    if (i2 > 0) {
      System.out.println(">");
    } else if (i2 < 0) {
      System.out.println("<");
    } else {
      System.out.println("=");
    }
  }
}





Double: doubleValue()

  
/*
 * Output:
 
10.234
 */
public class MainClass {
  public static void main(String args[]) {
    double degrees = Double.valueOf("10.234").doubleValue();
    System.out.println(degrees);
  }
}





Double: equals

  
/*
 * Output:
3.14159 = 3.14159 -> true
 * 
  
 */
public class MainClass {
  public static void main(String args[]) {
  Double d1 = new Double(3.14159);
  Double d2 = new Double("314159E-5");
  System.out.println(d1 + " = " + d2 + " -> " + d1.equals(d2));
  }
}





Double: floatValue()

  
public class Main {
  public static void main(String[] args) {
    Double dObj = new Double("10.50");
    byte b = dObj.byteValue();
    System.out.println(b);
    short s = dObj.shortValue();
    System.out.println(s);
    int i = dObj.intValue();
    System.out.println(i);
    float f = dObj.floatValue();
    System.out.println(f);
    double d = dObj.doubleValue();
    System.out.println(d);
  }
}
/*
10
10
10
10.5
10.5
*/





Double: intValue()

  
public class Main {
  public static void main(String[] args) {
    Double dObj = new Double("10.50");
    byte b = dObj.byteValue();
    System.out.println(b);
    short s = dObj.shortValue();
    System.out.println(s);
    int i = dObj.intValue();
    System.out.println(i);
    float f = dObj.floatValue();
    System.out.println(f);
    double d = dObj.doubleValue();
    System.out.println(d);
  }
}
/*
10
10
10
10.5
10.5
*/





Double: isInfinite()

  
/*
 * Output:
 * 
Infinity: true, false
NaN: false, true
 *  
 */
public class MainClass {
  public static void main(String args[]) {
  Double d1 = new Double(1/0.);
  Double d2 = new Double(0/0.);
  System.out.println(d1 + ": " + d1.isInfinite() + ", " + d1.isNaN());
  System.out.println(d2 + ": " + d2.isInfinite() + ", " + d2.isNaN());
  }
}





Double: isNaN()

  
/*
 * Output:
 * 
Infinity: true, false
NaN: false, true
 *  
 */
public class MainClass {
  public static void main(String args[]) {
  Double d1 = new Double(1/0.);
  Double d2 = new Double(0/0.);
  System.out.println(d1 + ": " + d1.isInfinite() + ", " + d1.isNaN());
  System.out.println(d2 + ": " + d2.isInfinite() + ", " + d2.isNaN());
  }
}





Double.MAX_VALUE

  
/*
 * Output:
 
1.7976931348623157E308
 */
public class MainClass {
  public static void main(String args[]) {
    System.out.println(Double.MAX_VALUE);
  }
}





Double.MIN_VALUE

  
/*
 * Output:
 
4.9E-324
 */
public class MainClass {
  public static void main(String args[]) {
    System.out.println(Double.MIN_VALUE);
  }
}





Double.NEGATIVE_INFINITY

  
/*
 * Output:
 
-Infinity
 */
public class MainClass {
  public static void main(String args[]) {
    System.out.println(Double.NEGATIVE_INFINITY);
  }
}





Double: parseDouble(String s)

  

public class Main {
  public static void main(String[] argv) throws Exception {
    double d = Double.parseDouble("123.4e10");
    System.out.println(d);
  }
}





Double.POSITIVE_INFINITY

  
/*
 * Output:
 
Infinity
 */
public class MainClass {
  public static void main(String args[]) {
    System.out.println(Double.POSITIVE_INFINITY);
  }
}





Double: shortValue()

  
public class Main {
  public static void main(String[] args) {
    Double dObj = new Double("10.50");
    byte b = dObj.byteValue();
    System.out.println(b);
    short s = dObj.shortValue();
    System.out.println(s);
    int i = dObj.intValue();
    System.out.println(i);
    float f = dObj.floatValue();
    System.out.println(f);
    double d = dObj.doubleValue();
    System.out.println(d);
  }
}
/*
10
10
10
10.5
10.5
*/





Double: toString(double d)

  

public class Main {
  public static void main(String[] args) {
    double d = 8.48;
    String s = Double.toString(d);
  }
}





Double: valueOf(String stringValue)

  
/*
 * Output:
 
10.234
 */
public class MainClass {
  public static void main(String args[]) {
    double degrees = Double.valueOf("10.234").doubleValue();
    System.out.println(degrees);
  }
}





new Double(double value)

  
/*
 * Output:
3.14159 = 3.14159 -> true
 * 
  
 */
public class MainClass {
  public static void main(String args[]) {
  Double d1 = new Double(3.14159);
  Double d2 = new Double("314159E-5");
  System.out.println(d1 + " = " + d2 + " -> " + d1.equals(d2));
  }
}





new Double(String stringValue) "-5"

  
/*
 * Output:
3.14159 = 3.14159 -> true
 * 
  
 */
public class MainClass {
  public static void main(String args[]) {
  Double d1 = new Double(3.14159);
  Double d2 = new Double("314159E-5");
  System.out.println(d1 + " = " + d2 + " -> " + d1.equals(d2));
  }
}


Источник — «http://jexp.ru/index.php?title=Java_by_API/java.lang/Double&oldid=2056»