How to convert String to primitive type value?

Given the str reference which refers to an instance of String without leading and trailing white space:

• Convert String to int:

  try {
    int i = Integer.parseInt(str);
    /* or */
    Integer I = Integer.valueOf(str);
    int i1 = I.intValue();
  } 
  catch (NumberFormatException e){
    ;
  }
  

  Here is another example for the string presents a hexdecimal string:

  try {
    int i = Integer.parseInt(str, 16 );
  } 
  catch (NumberFormatException e){
    ;
  }
  

  Note: Parses the string argument as a signed integer in the radix specified by the second argument. The characters in the string must all be digits, of the specified radix (as determined by whether Character.digit(char, int) returns a nonnegative value) except that the first character may be an ASCII minus sign '-' ('\u002D') to indicate a negative value. The resulting byte value is returned.

• Convert String to short:

  try {
    short s = Short.parseShort(str);
    /* or */
    Short S = Short.valueOf(str);
    short s1 = S.shortValue();
  } 
  catch (NumberFormatException e){
    ;
  }
  

• Convert String to byte:

   
  try {
    byte b = Byte.parseByte(str); 
    /* or */
    Byte B = Byte.valueOf(str);
    byte b1 = B.byteValue();
  } 
  catch (NumberFormatException e){
    ;
  }
  

• Convert String to long:

   
  try {
    long l = Long.parseLong(str); 
    /* or */
    Long L = Long.valueOf(str);
    long l1 = L.longValue();
  } 
  catch (NumberFormatException e){
    ;
  }
  

• Convert String to float:

   
  try {
    float f = Float.parseFloat(str); 
    float f1 = Float.valueOf(str).floatValue();
  } 
  catch (NumberFormatException e){
    ;
  }
  

• Convert String to double:

   
  try {
    double d= Double.parseDouble(str); 
    double d1 = Double.valueOf(str).doubleValue();
  } 
  catch (NumberFormatException e){
    ;
  }
  

• Convert String to boolean:

   
    Boolean B = Boolean.valueOf(str); 
    boolean b= B.booleanValue(); 
  

  No exception needs to catch because the Boolean returned represents the value true if the string argument is not null and is equal, ignoring case, to the string "true".

• Convert String to char:

  try { 
    char c= str.charAt(0); 
  } 
  catch (IndexOutOfBoundsException e){
   ;
  }
  

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