Static import inward Java allows to import static members of course of written report together with purpose them, every bit they are declared inward the same class. Static import is introduced inward Java v along amongst other features similar Generics, Enum, Autoboxing together with Unboxing together with variable declaration methods. Many programmer intend that using static import tin plough over the axe reduce code size together with allow y'all to freely purpose static plain of external course of written report without prefixing course of written report get upward on that. For representative without static import y'all volition access static constant MAX_VALUE of Integer course of written report every bit Integer.MAX_VALUE but past times using static import y'all tin plough over the axe import Integer.MAX_VALUE together with refer it every bit MAX_VALUE. Similar to regular import statements, static import every bit good allows wildcard * to import all static members of a class. In adjacent department nosotros volition encounter Java plan to demonstrate How to purpose static import statements to import static fields.
Static import representative inward Java
In this static import example, nosotros accept imported constants Integer.MAX_VALUE together with Integer.MIN_VALUE statically together with printing in that place value without prefixing class name on that. package test;
import static java.lang.Integer.MAX_VALUE;
import static java.lang.Integer.MIN_VALUE;
/**
*
* Java plan to demonstrate How to purpose static import inward Java 5
* By using static import y'all tin plough over the axe purpose static plain of external class
* every bit they are declared inward same class.
*
* @author Javin Paul
*/
public class StaticImportExample {
public static void main(String args[]) {
//without Static import
System.out.println("Maximum value of int variable inward Java without " +
import static java.lang.Integer.MAX_VALUE;
import static java.lang.Integer.MIN_VALUE;
/**
*
* Java plan to demonstrate How to purpose static import inward Java 5
* By using static import y'all tin plough over the axe purpose static plain of external class
* every bit they are declared inward same class.
*
* @author Javin Paul
*/
public class StaticImportExample {
public static void main(String args[]) {
//without Static import
System.out.println("Maximum value of int variable inward Java without " +
"static import : " + Integer.MAX_VALUE);
System.out.println("Minimum value of int variable inward Java without " +
System.out.println("Minimum value of int variable inward Java without " +
static import : " + Integer.MIN_VALUE);
//after static import inward Java 5
System.out.println("Maximum value of int variable using " +
//after static import inward Java 5
System.out.println("Maximum value of int variable using " +
static import : " + MAX_VALUE);
System.out.println("Minimum value of int variable using" +
System.out.println("Minimum value of int variable using" +
static import : " + MIN_VALUE);
}
}
Output:
Maximum value of int variable inward Java without static import : 2147483647
Minimum value of int variable inward Java without static import : -2147483648
Maximum value of int variable using static import : 2147483647
Minimum value of int variable using static import : -2147483648
}
}
Output:
Maximum value of int variable inward Java without static import : 2147483647
Minimum value of int variable inward Java without static import : -2147483648
Maximum value of int variable using static import : 2147483647
Minimum value of int variable using static import : -2147483648
If y'all aspect at import statements import static java.lang.Integer.MAX_VALUE, its written every bit import static rather than static import, hence only beware of that. We are non using * wildcard hither together with importing exclusively selected static fellow member but y'all tin plough over the axe every bit good purpose import static java.lang.Integer.* to import all static fields inward ane go.
Advantages of Static Import inward Java
Main wages of using static import inward Java is saving keystrokes. If y'all are oft using System.out.println() statements together with tried of typing it, y'all tin plough over the axe static import System.out or System.* together with afterward y'all tin plough over the axe type out.println() inward your code, Though I would propose to purpose this Eclipse shortcut to generate System.out.println statement which is much faster than static import. This is the sort of usage I encounter ane tin plough over the axe produce goodness from static import, other than that static import is only extension of regular import declaration inward Java. Similar to static plain y'all tin plough over the axe every bit good import static method inward your class, generally inward representative of Utility classes.
Drawback of Static Import inward Java
Many Java programmer fence against static import amongst argue that it reduces readability together with goes against how static plain should survive used i.e. prefixed amongst course of written report get upward e.g. Integer.MAX_VALUE. Static import has around other drawback inward damage of conflicts, in ane lawsuit y'all static import Integer.MAX_VALUE y'all tin plough over the axe non purpose MAX_VALUE every bit variable inward your programmer, compiler volition throw error. Similarly if y'all static import both Integer.MAX_VALUE together with Long.MAX_VALUE together with refer them inward code every bit MAX_VALUE, y'all volition larn next compile time fault :
java.lang.ExceptionInInitializerError
Caused by: java.lang.RuntimeException: Uncompilable rootage code - MAX_VALUE is already defined inward a static single-type import
at test.StaticImportExample.(StaticImportExample.java:6)
Could non uncovering the primary class: test.StaticImportExample. Program volition exit.
Exception inward thread "main" Java Re
Summary
Finally few points worth remembering most static import inward Java :
1) Static import statements are written every bit "import static" inward code together with non "static import".
2) If y'all import ii static fields amongst same get upward explicitly e.g. Integer.MAX_VALUE together with Long.MAX_VALUE together with then Java volition throw compile fourth dimension error. But if other static modifier is non imported explicitly e.g. y'all accept imported java.lang.Long.*, MAX_VALUE volition refer to Integer.MAX_VALUE.
3) Static import doesn't meliorate readability every bit expected, every bit many Java programmer prefer Integer.MAX_VALUE which is clear that which MAX_VALUE are y'all referring.
4) You tin plough over the axe apply static import statement non exclusively on static fields but every bit good on static methods inward Java.
That's all on What is static import inward Java 5, What is advantages together with drawbacks of using static import inward Java plan together with how to purpose static import inward Java. Honestly, its been almost a decade amongst Java v released but I accept rarely used static import statements. May survive inward hereafter I may figure out a potent convincing argue to purpose static import
Further Learning
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