java.lang.Object
- org.djutils.exceptions.Throw

```
public final class Throw
extends Object
```
The Throw class has a number of static methods that make it easy to throw an exception under conditions for any Exception class, including the standard Java exceptions and exceptions from libraries that are used in the project. Instead of:
```
 if (car == null)
 {
     throw new NullPointerException("Car may not be null.");
 }
 if (Double.isNaN(car.getPosition()))
 {
     throw new IllegalArgumentException("Position of car " + car + " is NaN.");
 }
 
```
we can write:
```
 Throw.whenNull(car, "Car may not be null.");
 Throw.when(Double.isNaN(car.getPosition()), IllegalArgumentException.class, "Position of car %s is NaN.", car);
 
```
The exception message can be formatted with additional arguments, such that the overhead of building the exception message only occurs if the exception condition is met. All methods have a version where the first parameter is returned. Thereby, the Throw can be used as part of a super(...) call in a constructor.
Copyright (c) 2016-2023 Delft University of Technology, Jaffalaan 5, 2628 BX Delft, the Netherlands. All rights reserved. See for project information https://djutils.org. The DJUTILS project is distributed under a three-clause BSD-style license, which can be found at https://djutils.org/docs/license.html.
Author:

Alexander Verbraeck, Peter Knoppers, Wouter Schakel

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method	Description
`static void`	`throwUnchecked(Throwable e)`	Throw an unchecked exception for a method with a fixed signature (e.g., extending a method from a library that cannot be changed), without having to declare the exception, which can be impossible when extending a method.
`static <T extends Throwable> void`	`when(boolean condition, Class<T> throwableClass, String message)`	Throw a Throwable (such as an Exception or Error) if a condition is met, e.g.
`static <T extends Throwable> void`	`when(boolean condition, Class<T> throwableClass, String message, Object arg)`	Throw a Throwable (such as an Exception or Error) if a condition is met, e.g.
`static <T extends Throwable> void`	`when(boolean condition, Class<T> throwableClass, String message, Object arg1, Object arg2)`	Throw a Throwable (such as an Exception or Error) if a condition is met, e.g.
`static <T extends Throwable> void`	`when(boolean condition, Class<T> throwableClass, String message, Object arg1, Object arg2, Object arg3)`	Throw a Throwable (such as an Exception or Error) if a condition is met, e.g.
`static <T extends Throwable> void`	`when(boolean condition, Class<T> throwableClass, String message, Object arg1, Object arg2, Object arg3, Object... args)`	Throw a Throwable (such as an Exception or Error) if a condition is met, e.g.
`static <T extends Throwable,O> O`	`when(O object, boolean condition, Class<T> throwableClass, String message)`	Throw a Throwable (such as an Exception or Error) if a condition is met, e.g.
`static <T extends Throwable,O> O`	`when(O object, boolean condition, Class<T> throwableClass, String message, Object arg)`	Throw a Throwable (such as an Exception or Error) if a condition is met, e.g.
`static <T extends Throwable,O> O`	`when(O object, boolean condition, Class<T> throwableClass, String message, Object arg1, Object arg2)`	Throw a Throwable (such as an Exception or Error) if a condition is met, e.g.
`static <T extends Throwable,O> O`	`when(O object, boolean condition, Class<T> throwableClass, String message, Object arg1, Object arg2, Object arg3)`	Throw a Throwable (such as an Exception or Error) if a condition is met, e.g.
`static <T extends Throwable,O> O`	`when(O object, boolean condition, Class<T> throwableClass, String message, Object arg1, Object arg2, Object arg3, Object... args)`	Throw a Throwable (such as an Exception or Error) if a condition is met, e.g.
`static <O> O`	`whenNull(O object, String message)`	Throw a NullPointerException if object is null, e.g.
`static <O> O`	`whenNull(O object, String message, Object arg)`	Throw a NullPointerException if object is null, e.g.
`static <O> O`	`whenNull(O object, String message, Object arg1, Object arg2)`	Throw a NullPointerException if object is null, e.g.
`static <O> O`	`whenNull(O object, String message, Object arg1, Object arg2, Object arg3)`	Throw a NullPointerException if object is null, e.g.
`static <O> O`	`whenNull(O object, String message, Object arg1, Object arg2, Object arg3, Object... args)`	Throw a NullPointerException if object is null, e.g.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait