I have several java files in a package and all of them have the same import blocks e.g :
package org.ezim.core;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.Socket;
import org.ezim.core.Ezim;
import org.ezim.core.EzimDtxSemantics;
import org.ezim.core.EzimLogger;
import org.ezim.ui.EzimFileOut;
import org.ezim.ui.EzimMain;
It looks awful having the same batches of code in each file and i want to refactor it.
I was wondering if its possible to put all these imports in a single java file then use a single line in all the other java files to call them.
Its like the extend function for classes (for variables) , but i want one for the imports.
Thanks
No. That isn't possible. What is possible is not using imports at all, instead you can use fully qualified class names like
org.ezim.core.Ezim ezim = new org.ezim.core.Ezim(); // <-- not import needed.
You can always use * sign to import multiple classes from one package, but thus watch for name clashes.
Related
I have this class that I want to import into another class that is outside the previous class folder.
So, I have a GoogleDriveAPI class, which I want to import to DocumentServices class.
on top of my GoogleDriveAPI class there is this line
package org.ofbiz.ClientManagementServices;
but when I try to import it to DocumentServices class with this line below
import org.ofbiz.clientmanagementservices.GoogleDriveAPI;
I get this error below,
error: package org.ofbiz.clientmanagementservices does not exist
[javac17] import org.ofbiz.clientmanagementservices.GoogleDriveAPI;
What might be the problem with my import because I am 100% sure I am doing the right thing?
Java packages are cas sensitive.
You should change the import to :
import org.ofbiz.ClientManagementServices.GoogleDriveAPI;
I am working on a somewhat large project with many subdirectories. I am, however, coming across an issue of importing classes from within another directory. The directory structure is as so:
main.dir
repository.dir
Bill.java
transaction.dir
AutomaticBillPay.java
How can I import Bill into AutomaticBillPay?
I have tried may iterations of:
package main;
package main.repositorysys;
import main.repositorysys.Bill;
import repositorysys.Bill;
import Bill;
Sadly, the only line that compiles is the first: package main;. Any tips / direction will help!
You can achieve it through this
/*Declare your class package */
package main.transactionsubsys;
/*import the classes you want */
import main.repositorysys.Bill;
/*Write your class*/
public class AutomaticBillPay {
/*AutomaticBillPay code */
}
Your AutomaticBillPay should look like this:
package main.transaction;
import main.repository.Bill;
public class AutomaticBillPay {
// your class implementation here
}
Not sure where repositorysys came from?
package should be the full path to your encompassing directory
import should be the full path to the class you want to import
I have a problem with the following code:
parent.strokeCap(SQUARE);
I tried importing these:
import processing.core.PApplet;
import processing.core.PGraphics;
import processing.core.PShape;
import processing.core.PConstants;
import processing.core.PShapeSVG;
import processing.core.PGraphicsJava2D;
import processing.core.PStyle;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.Arrays;
But the problem persists. Do I have to make another import? I tried to find what value SQUARE represents but was unable to find any info about what it should contain.
note that you're not writing "Processing", you're writing Java, with all the regular Java formalisms and requirements, with some of your imports simply being the Processing API library. If you need a library constant, PConstants.SQUARE will get you there.
What is the difference between "import java.lang.Integer;" and " import java.lang.Integer.*;".
I have read on internet that the Integer is a class inside the lang package. If this is true then then " import java.lang.Integer.*;" should give an compilation error because the statement " import java.lang.Integer.*;" mean to import all the classes inside the package Integer but Integer is not a package it is a class.
But both statements compile without any error.
Please clarify. Thanks a lot in advance.
If i will write "import java.lang.Integer;" so its a particular find Integer Function only.if I will write "import java.lang.Integer.*; so Its all function Included which Extension of "java.lang.integer".
import java.lang.Integer.*;
The above statement is a less common form of import, allows you to import the public nested classes of an enclosing class(in this case Integer class).
Consider for example, if the graphics.Rectangle class contained useful nested classes, such as Rectangle.DoubleWide and Rectangle.Square, you could import Rectangle and its nested classes by using the following two statements.
import graphics.Rectangle;
import graphics.Rectangle.*;
Be aware that the second import statement will not import Rectangle.
I am new in using eclipse java using multiple .java files. My eclipse java project consist of one project file two package files, each with one .java class
My 2nd java class import the 1st java class/package, like so
VerifyLogin.java
package VerifyLogin;
import ArgumentCountException;
ArgumentCountException.java
// ...
The problem is VerifyLogin.java is getting an error
Import ArgumentCountException cannot be resolved
Or any reference I have to ArgumentCountException cannot be resolved to a type.
In java if you need to import a class then you need to use the full qualified name for that class, as the following:
import packageName.YourClass;
For Example, if your need to use Scanner class, then you need to import it as:
import java.util.Scanner;
But if the class was withing the same package, you don't need to import it.
When importing your class, it should be done as below:
//Current package name for the VerifyLogin Class (All package names should be lowercase by convention)
package packageforcurrentclass;
//Import statements: import thedependencyclasspackage.thedependencyclassname
import exceptionpackage.ArgumentCountException;
public class VerifyLogin
{
...
}