Java Integer getInteger() Method

There are three different types of Java getInteger() methods which can be differentiated depending on its parameter. These are:

Java Integer getInteger(String nm) Method
Java Integer getInteger(String nm, int val) Method
Java Integer getInteger(String nm, Integer val) Method

1. Java Integer getInteger(String nm) Method:

The getInteger(String nm) method is a method of Integer class under java.lang package. This method determines the integer value of the system property with the specified name of method argument. If there is no property with the specified name of method argument, if the specified name is empty or null or if the property does not have the correct numeric format, it will returned null.

Syntax:

Following is the declaration of getInteger(String nm) method:

Parameter:

DataType	Parameter	Description	Required/Optional
String	nm	It is the system property name from which we get the value as an integer object.	Required

Returns:

The getInteger(String nm) method will returns the value of the property specified as method argument as an Integer object.

Exceptions:

Compatibility Version:

Java 1.2 and above

Example 1

public class IntegerGetIntegerExample1 {
	public static void main(String[] args) {		
		// It determines the integer value of the system property 
	      String str = "sun.arch.data.model";
	      System.out.println("Value = "+Integer.getInteger(str));	   
	      //It will Prints null
	      str = "Java";
	      System.out.println("Value = "+Integer.getInteger(str));
		}
}

Output:

sun.arch.data.model is the Java System property which determines the version of the JVM is used - 32 or 64bit.

Value = 64
Value = null

Example 2

public class IntegerGetIntegerExample2 {
	public static void main(String[] args) {		
		// Get one default system property
		System.out.println("Default property: "+Integer.getInteger("sun.arch.data.model"));
		// set a custom property
		System.setProperty("test.integer", "100");
		// get the value of the custom property we set
		System.out.println("Custom Property: " +Integer.getInteger("test.integer"));
		}
}

Output:

Default property: 64
Custom Property: 100

Example 3

import java.util.Scanner;
public class IntegerGetIntegerExample3 {
	public static void main(String[] args) {
		System.out.print("Enter the desired input string: ");
		Scanner readString = new Scanner(System.in);
		// It determines the integer value of the system property 
		String str= readString.next();	     
	      System.out.println("Default Value = "+Integer.getInteger(str));	
	      readString.close();
	      //It will Prints null
	      str = "Java";
	      System.out.println("Custom Value = "+Integer.getInteger(str));
		}
}

Output:

Enter the desired input string: sun.arch.data.model
Default Value = 64
Custom Value = null

2. Java Integer getInteger(String nm, int val) Method:

The getInteger(String nm, int val) method is a method of Integer class under java.lang package. This method determines the integer value of the system property with the specified name of method argument.

The first argument is treated as the name of a system property. The string value of this property is then interpreted as an integer value and an Integer object representing this value is returned.

The second argument is the default value. An Integer object that represents the value of the second argument is returned if there is no property of the specified name, if the property does not have the correct numeric format, or if the specified name is empty or null.

Syntax:

Following is the declaration of getInteger(String nm, int val) method:

Parameter:

DataType	Parameter	Description	Required/Optional
String	nm	It is the system property name from which we get the value as an integer object.	Required
Int	val	It is the default value specified by user which returned if property were not found.	Required

Returns:

The getInteger(String nm, int val) method returns the value of the system property name specified as method argument as an Integer object and if not found, the default value will be returned as specified by the user.

Exceptions:

Compatibility Version:

Java 1.2 and above

Example 1

public class IntegerGetIntegerDemo1 {
	public static void main(String[] args) {		
		String myKey = "MySystemKey";
	      System.setProperty(myKey, "102");
	      System.out.println(Integer.getInteger(myKey));
	      System.out.println(Integer.getInteger("NoExist",999));
		}
}

Output:

102
999

Example 2

public class IntegerGetIntegerDemo2 {
	public static void main(String[] args) {		
		// Get one default system property
				System.out.println("System Property: "+Integer.getInteger("java.vm.specification.vendor", 123));
				// without default value
				System.out.println("Default property: "+ Integer.getInteger("sun.arch.data.model"));
				// set a custom property
				System.setProperty("test.integer", "100");
				// get the value of the custom property we set
				System.out.println("Custom Property:" + Integer.getInteger("test.integer"));
				System.out.println("Custom Property: " + Integer.getInteger("none.existent",124));
		}
}

Output:

System Property: 123
Default property: 64
Custom Property:100
Custom Property: 124

Example 3

import java.util.Scanner;
public class IntegerGetIntegerDemo3 {
	public static void main(String[] args) {		
		Integer i = new Integer(25);
		System.out.println("Enter the desired system property:");	     	      
		Scanner readString = new Scanner(System.in);
		String str = readString.next();
		readString.close();
		//Returns the integer value of the system property
	      System.out.println("Default Value: "+Integer.getInteger(str, i));
	      //Returns default value as system property "abcd" does not exist
	      System.out.println("Custom Value: "+Integer.getInteger("abcd", i));
		}
}

Output:

Enter the desired system property:
sun.arch.data.model
Default Value: 64
Custem Value: 25

3. Java Integer getInteger(String nm, Integer val) Method:

The getInteger( String nm, Integer val ) method is a method of Integer class under java.lang package. This method determines the integer value of the system property with the specified name of method argument.

The first argument is treated as the name of a system property. System properties are accessible through the System.getProperty(java.lang.String) method. The string value of this property is then interpreted as an integer value and an Integer object representing this value is returned.

If the property value begins with the two ASCII characters 0x or the ASCII character #, not followed by a minus sign, rest of it is parsed as a hexadecimal integer exactly.
If the property value begins with the ASCII character 0 followed by another character, rest of it is parsed as an octal integer exactly.
Otherwise, the property value is parsed as a decimal integer.

The second argument is the default value. This value is returned if there is no property of the specified name, if the property does not have the correct numeric format, or if the specified name is empty or null.

Syntax:

Following is the declaration of getInteger(String nm, Integer val) method:

Parameter:

DataType	Parameter	Description	Required/Optional
String	nm	It is the system property name from which we get the value as an integer object.	Required
Integer	val	It is the deafult value specified by user which returned if property were not found.	Required

Returns:

The getInteger(String nm, Integer val) method returns the value of the system property name specified as method argument as an Integer object and if not found, the default value will be returned as specified by the user.

Exceptions:

Compatibility Version:

Java 1.2 and above

Example 1

public class IntegerGetIntegerString1 {
	public static void main(String[] args) {
		// Print default system property
		System.out.println(Integer.getInteger("java.vm.specification.vendor", new Integer(133)));
		// without default value
		System.out.println("Default property:"+ Integer.getInteger("sun.arch.data.model"));
		// set a custom property
		System.setProperty("test.integer", "100");
		// Print the value of the custom property
		System.out.println("Custom Property: " + Integer.getInteger("test.integer"));
		System.out.println("Custom Property: " + Integer.getInteger("not.exist", new Integer(105)));

	}
}

Output:

133
Default property:64
Custom Property: 100
Custom Property: 105

Example 2

import java.util.Scanner;
public class IntegerGetIntegerString2 {
	public static void main(String[] args) {
	  System.out.print("Enter the desired System Property name: ");
	  Scanner readString = new Scanner(System.in);
	  String str = readString.next();
	  readString.close();
	  Integer i = new Integer(25);	     
	  //Returns the Integer value of the system property 
	  System.out.println("System Property Value: "+Integer.getInteger(str, i));
	  //Returns default specified value as system property "abcd" does not exist 
	  System.out.println("Custom Value: "+Integer.getInteger("abcd", i));
	  }
}

Output:

Enter the desired System Property name: sun.arch.data.model
System Property Value: 64
Custom Value: 25

Example 3

public class IntegerGetIntegerString3 {
	public static void main(String[] args) {		
		String myKey = "MySystemKey";
	    System.setProperty(myKey, "102");
	    System.out.println(Integer.getInteger(myKey));
	    System.out.println(Integer.getInteger("NoExist",new Integer(950)));
		}
}

Output: