Applying Package Imports
Now that you understand the basics of importing packages in Java, let's explore how to apply package imports in your code.
Importing Classes from Packages
To use a class from a package, you need to either import the specific class or use the fully qualified name of the class. Here's an example:
// Importing a specific class
import java.util.ArrayList;
public class MyClass {
public void example() {
ArrayList<String> myList = new ArrayList<>();
}
}
In this example, we import the ArrayList class from the java.util package, allowing us to use ArrayList directly in our code without having to specify the full package name.
Importing Packages with Wildcards
As mentioned earlier, you can use the wildcard * to import all classes from a package. This can be useful when you need to use multiple classes from the same package. Here's an example:
// Importing all classes from the java.util package
import java.util.*;
public class MyClass {
public void example() {
ArrayList<String> myList = new ArrayList<>();
HashMap<String, Integer> myMap = new HashMap<>();
}
}
In this example, we import all classes from the java.util package using the wildcard *. This allows us to use ArrayList and HashMap directly in our code without having to specify the full package name.
Avoiding Naming Conflicts
As mentioned earlier, you need to be careful when importing packages to avoid naming conflicts. If two packages contain classes with the same name, you will need to use the fully qualified name of the class to avoid ambiguity.
Here's an example of how to handle a naming conflict:
import com.labex.util.MyClass;
import com.example.util.MyClass;
public class MyMainClass {
public void example() {
// Use the fully qualified name to reference the classes
com.labex.util.MyClass labexMyClass = new com.labex.util.MyClass();
com.example.util.MyClass exampleMyClass = new com.example.util.MyClass();
}
}
In this example, we import two classes named MyClass from different packages. To use these classes, we need to reference them using their fully qualified names to avoid any ambiguity.
By understanding how to apply package imports in your Java code, you can effectively organize and manage your codebase, making it easier to develop and maintain your Java applications.
