Autoboxing pitfalls

1. Use carefully Boolean in setter method for boolean attribute:

EXAMPLE :
DON'T DO THIS (throws null pointer exception):

public

class BooleanMethod {

boolean attribute = false;

/**

*

@return the attribute

*/

public boolean isAttribute() {

return attribute;

}

/**

*

@param attribute the attribute to set

*/

public void setAttribute(boolean attribute) {

this.attribute = attribute;

}

public static void main (String [] args) {

BooleanMethod obj =

new BooleanMethod();

Boolean condition =

null;

obj.setAttribute(condition);

System.

out.println(obj.isAttribute());

}

}

Exception in thread "main"

java.lang.NullPointerExceptionat BooleanMethod.main(BooleanMethod.java:23)

BETTER

public

class BooleanMethod {

boolean attribute = false;

/**

*

@return the attribute

*/

public boolean isAttribute() {

return attribute;

}

/**

*

@param attribute the attribute to set

*/

public void setAttribute(boolean attribute) {

this.attribute = attribute;

}

public static void main (String [] args) {

BooleanMethod obj =

new BooleanMethod();

Boolean condition =

null;

if (condition != null){

obj.setAttribute(condition);

}

System.

out.println(obj.isAttribute());

condition = Boolean.

TRUE;

if (condition != null){

obj.setAttribute(condition);

}

System.

out.println(obj.isAttribute());

}

}