CLASES NUMERICAS JAVA WINDOWS

UNIDAD 1: JAVA ELEMENTOS BASICOS

TEMA 5: JAVA CLASES ESPECIALES

En java como lenguaje de programacion orientado a objetos existen aparte de la clase String vista en el tema anterior cuatro clases especiales descendientes de la clase numbers que contienen una serie de metodos que facilitan la interaccion con los usuarios de nuestras aplicaciones en captura y despliegue de datos numericos.

Sin embargo su caracteristica mas importante a tomar en cuenta es que objetos numericos derivados de estaS clase no pueden entrar a operaciones DIRECTAMENTE ni recibir el resultado de operaciones.

Class Integer

public  final  class  java.lang.**Integer **extends  java.lang.**Number**  
{
        // Fields
    public final static int **MAX_VALUE**; 
    public final static int **MIN_VALUE**;

        // Constructors
    public **Integer**(int  value);        
    public **Integer**(String  s);

        // Methods
    public double **doubleValue**();
    public boolean **equals**(Object  obj);        
    public float **floatValue**(); 
    public static Integer **getInteger**(String  nm);      
    public static Integer **getInteger**(String  nm, int  val);    
    public static Integer **getInteger**(String  nm, Integer  val);        
    public int **hashCode**();     
    public int **intValue**();     
    public long **longValue**();   
    public static int **parseInt**(String  s);     
    public static int **parseInt**(String  s, int  radix); 
    public static String **toBinaryString**(int  i);       
    public static String **toHexString**(int  i);  
    public static String **toOctalString**(int  i);        
    public String **toString**();  
    public static String **toString**(int  i);     
    public static String  **toString**(int  i, int  radix);        
    public static Integer **valueOf**(String  s);  
    public static Integer **valueOf**(String  s, int  radix);      
}
Esta clase convierte un dato de tipo int a un objeto.
Este objeto contiene un solo campo de tipo int.
Pero tambien el objeto contiene una serie de metodos para convertir un valor int a una String y tambien para convertir una String a int.
Ademas de otros metodos de igual utilidad.

* Clase y notas tomadas directamente de java.sun

Class Double

public final class java.lang.Double extends java.lang.Number

{
        // Fields
    public final static double **MAX_VALUE**;      
    public final static double **MIN_VALUE**;      
    public final static double **NaN**;    
    public final static double **NEGATIVE_INFINITY**;      
    public final static double **POSITIVE_INFINITY**;

        // Constructors
    public **Double**(double  value);      
    public **Double**(String  s);  
        // Methods
    public static long **doubleToLongBits**(double  value);        
    public double **doubleValue**();       
    public boolean **equals**(Object  obj); 
    public float **floatValue**(); 
    public int **hashCode**();     
    public int **intValue**();     
    public boolean **isInfinite**();       
    public static boolean **isInfinite**(double  v);       
    public boolean **isNaN**();    
    public static boolean **isNaN**(double  v);    
    public static double **longBitsToDouble**(long  bits); 
    public long **longValue**();   
    public String **toString**();  
    public static String **toString**(double  d);  
    public static Double **valueOf**(String  s);   
}

* La misma fuente y las mismas notas de la clase anterior

Class Float

public  final  class  java.lang.**Float **extends  java.lang.**Number**  
{
        // Fields
    public final static float **MAX_VALUE**;       
    public final static float **MIN_VALUE**;       
    public final static float **NaN**;     
    public final static float **NEGATIVE_INFINITY**;       
    public final static float **POSITIVE_INFINITY**;       
  // Constructors
    public **Float**(double  value);       
    public **Float**(float  value);        
    public **Float**(String  s);   
        // Methods
    public double **doubleValue**();       
    public boolean **equals**(Object  obj); 
    public static int **floatToIntBits**(float  value);    
    public float **floatValue**(); 
    public int **hashCode**();     
    public static float **intBitsToFloat**(int  bits);     
    public int **intValue**();     
    public boolean **isInfinite**();       
    public static boolean **isInfinite**(float  v); 
    public boolean **isNaN**();    
    public static boolean **isNaN**(float  v);     
    public long **longValue**();   
    public String **toString**();  
    public static String **toString**(float  f);   
    public static Float **valueOf**(String  s);    
}

La misma fuente y notas anteriores —- Class Long public final class java.lang.Long extends java.lang.Number { Fields public final static long MAX_VALUE; public final static long MIN_VALUE; Constructors public Long(long value); public Long(String s); // Methods public double doubleValue(); public boolean equals(Object obj); public float floatValue(); public static Long getLong(String nm); public static Long getLong(String nm, long val); public static Long getLong(String nm, Long val); public int hashCode(); public int intValue(); public long longValue(); public static long parseLong(String s); public static long parseLong(String s, int radix); public static String toBinaryString(long i); public static String toHexString(long i); public static String toOctalString(long i); public String toString(); public static String toString(long i); public static String toString(long i, int radix); public static Long valueOf(String s); public static Long valueOf(String s, int radix); } * La misma fuente y notas anteriores

*CLASS STRING

Constructores: String() Constructs a new empty String.String(String) Constructs a new String that is a copy of the specified String.String(char[]) Constructs a new String whose initial value is the specified array of characters.String(char[], int, int) Constructs a new String whose initial value is the specified sub array of characters.String(byte[], int, int, int) Constructs a new String whose initial value is the specified sub array of bytes.String(byte[], int) Constructs a new String whose value is the specified array of bytes.String(StringBuffer) Construct a new string whose value is the current contents of the given string buffer METODOS:**

charAt(int) Returns the character at the specified index.compareTo(String) Compares this String to another specified String.concat(String) Concatenates the specified string to the end of this String.copyValueOf(char[], int, int) Returns a String that is equivalent to the specified character array.copyValueOf(char[]) Returns a String that is equivalent to the specified character array.endsWith(String) Determines whether the String ends with some suffix.equals(Object) Compares this String to the specified object.equalsIgnoreCase(String) Compares this String to another object.getBytes(int, int, byte[], int) Copies characters from this String into the specified byte array.getChars(int, int, char[], int) Copies characters from this String into the specified character array.hashCode() Returns a hashcode for this String.indexOf(int) Returns the index within this String of the first occurrence of the specified character.indexOf(int, int) Returns the index within this String of the first occurrence of the specified character, starting the search at fromIndex.indexOf(String) Returns the index within this String of the first occurrence of the specified substring.indexOf(String, int) Returns the index within this String of the first occurrence of the specified substring.intern() Returns a String that is equal to this String but which is guaranteed to be from the unique String pool.lastIndexOf(int) Returns the index within this String of the last occurrence of the specified character.lastIndexOf(int, int) Returns the index within this String of the last occurrence of the specified character.lastIndexOf(String) Returns the index within this String of the last occurrence of the specified substring.lastIndexOf(String, int) Returns the index within this String of the last occurrence of the specified substring.length() Returns the length of the String.regionMatches(int, String, int, int) Determines whether a region of this String matches the specified region of the specified String.regionMatches(boolean, int, String, int, int) Determines whether a region of this String matches the specified region of the specified String.replace(char, char) Converts this String by replacing all occurences of oldChar with newChar.startsWith(String, int) Determines whether this String starts with some prefix.startsWith(String) Determines whether this String starts with some prefix.substring(int) Returns the substring of this String.substring(int, int) Returns the substring of a String.toCharArray() Converts this String to a character array.toLowerCase() Converts all of the characters in this String to lower case.toString() Converts this String to a String.toUpperCase() Converts all of the characters in this String to upper case.trim() Trims leading and trailing whitespace from this String.valueOf(Object) Returns a String that represents the String value of the object.valueOf(char[]) Returns a String that is equivalent to the specified character array.valueOf(char[], int, int) Returns a String that is equivalent to the specified character array.valueOf(boolean) Returns a String object that represents the state of the specified boolean.valueOf(char) Returns a String object that contains a single charactervalueOf(int) Returns a String object that represents the value of the specified integer.valueOf(long) Returns a String object that represents the value of the specified long.valueOf(float) Returns a String object that represents the value of the specified float.valueOf(double) Returns a String object that represents the value of the specified double.