Java Pocket Guide

Chapter 8. Java Modifiers

Modifiers, which are Java keywords, may be applied to classes, interfaces, constructors, methods, and data members.

Table 8-1 lists the Java modifiers and their applicability.

Table 8-1. Java modifiers

Modifier	Class	Interface	Constructor	Method	Data member
Access modifiers
package-private	Yes	Yes	Yes	Yes	Yes
private	No	No	Yes	Yes	Yes
protected	No	No	Yes	Yes	Yes
public	Yes	Yes	Yes	Yes	Yes
Other modifiers
abstract	Yes	Yes	No	Yes	No
final	Yes	No	No	Yes	Yes
native	No	No	No	Yes	No
strictfp	Yes	Yes	No	Yes	No
static	No	No	No	Yes	Yes
synchronized	No	No	No	Yes	No
transient	No	No	No	No	Yes
volatile	No	No	No	No	Yes

Access Modifiers

Access modifiers define the access privileges of classes, interfaces, constructors, methods, and data members. Access modifiers consist of public, private, and protected. If no modifier is present, the default access of package-private is used.

Figure 8-1 illustrates the visibility of the access modifiers, including the differences between classes that are public and package-private. Note that in the figure, the modifiers refer to both data members and methods.

Figure 8-1. Visibility of access modifiers

Table 8-2 provides details on the visibility when these access modifiers ...