Preconditions (Guava: Google Core Libraries for Java 29.0-android API)

java.lang.Object
- com.google.common.base.Preconditions

```
@GwtCompatible
public final class Preconditions
extends Object
```
Static convenience methods that help a method or constructor check whether it was invoked correctly (that is, whether its preconditions were met).
If the precondition is not met, the Preconditions method throws an unchecked exception of a specified type, which helps the method in which the exception was thrown communicate that its caller has made a mistake. This allows constructs such as
```
 public static double sqrt(double value) {
   if (value < 0) {
     throw new IllegalArgumentException("input is negative: " + value);
   }
   // calculate square root
 }
 
```
to be replaced with the more compact
```
 public static double sqrt(double value) {
   checkArgument(value >= 0, "input is negative: %s", value);
   // calculate square root
 }
 
```
so that a hypothetical bad caller of this method, such as:
```
 void exampleBadCaller() {
   double d = sqrt(-1.0);
 }
 
```
would be flagged as having called sqrt() with an illegal argument.
Performance

Avoid passing message arguments that are expensive to compute; your code will always compute them, even though they usually won't be needed. If you have such arguments, use the conventional if/throw idiom instead.
Depending on your message arguments, memory may be allocated for boxing and varargs array creation. However, the methods of this class have a large number of overloads that prevent such allocations in many common cases.
The message string is not formatted unless the exception will be thrown, so the cost of the string formatting itself should not be a concern.
As with any performance concerns, you should consider profiling your code (in a production environment if possible) before spending a lot of effort on tweaking a particular element.
Other types of preconditions

Not every type of precondition failure is supported by these methods. Continue to throw standard JDK exceptions such as NoSuchElementException or UnsupportedOperationException in the situations they are intended for.
Non-preconditions

It is of course possible to use the methods of this class to check for invalid conditions which are not the caller's fault. Doing so is not recommended because it is misleading to future readers of the code and of stack traces. See Conditional failures explained in the Guava User Guide for more advice. Notably, Verify offers assertions similar to those in this class for non-precondition checks.
java.util.Objects.requireNonNull()

Projects which use com.google.common should generally avoid the use of Objects.requireNonNull(Object). Instead, use whichever of checkNotNull(Object) or Verify.verifyNotNull(Object) is appropriate to the situation. (The same goes for the message-accepting overloads.)
Only %s is supported

Preconditions uses Strings.lenientFormat(java.lang.String, java.lang.Object...) to format error message template strings. This only supports the "%s" specifier, not the full range of Formatter specifiers. However, note that if the number of arguments does not match the number of occurrences of "%s" in the format string, Preconditions will still behave as expected, and will still include all argument values in the error message; the message will simply not be formatted exactly as intended.
More information

See the Guava User Guide on using Preconditions.
Since:

2.0

Author:

Kevin Bourrillion

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static void`	`checkArgument(boolean expression)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean expression, Object errorMessage)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, char p1)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, char p1, char p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, char p1, int p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, char p1, long p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, char p1, Object p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, int p1)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, int p1, char p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, int p1, int p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, int p1, long p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, int p1, Object p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, long p1)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, long p1, char p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, long p1, int p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, long p1, long p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, long p1, Object p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean expression, String errorMessageTemplate, Object... errorMessageArgs)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, Object p1)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, Object p1, char p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, Object p1, int p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, Object p1, long p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, Object p1, Object p2)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, Object p1, Object p2, Object p3)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static void`	`checkArgument(boolean b, String errorMessageTemplate, Object p1, Object p2, Object p3, Object p4)` Ensures the truth of an expression involving one or more parameters to the calling method.
`static int`	`checkElementIndex(int index, int size)` Ensures that `index` specifies a valid element in an array, list or string of size `size`.
`static int`	`checkElementIndex(int index, int size, String desc)` Ensures that `index` specifies a valid element in an array, list or string of size `size`.
`static <T> T`	`checkNotNull(T reference)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T reference, Object errorMessage)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, char p1)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, char p1, char p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, char p1, int p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, char p1, long p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, char p1, Object p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, int p1)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, int p1, char p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, int p1, int p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, int p1, long p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, int p1, Object p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, long p1)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, long p1, char p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, long p1, int p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, long p1, long p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, long p1, Object p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T reference, String errorMessageTemplate, Object... errorMessageArgs)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, Object p1)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, Object p1, char p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, Object p1, int p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, Object p1, long p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, Object p1, Object p2)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, Object p1, Object p2, Object p3)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static <T> T`	`checkNotNull(T obj, String errorMessageTemplate, Object p1, Object p2, Object p3, Object p4)` Ensures that an object reference passed as a parameter to the calling method is not null.
`static int`	`checkPositionIndex(int index, int size)` Ensures that `index` specifies a valid position in an array, list or string of size `size`.
`static int`	`checkPositionIndex(int index, int size, String desc)` Ensures that `index` specifies a valid position in an array, list or string of size `size`.
`static void`	`checkPositionIndexes(int start, int end, int size)` Ensures that `start` and `end` specify valid positions in an array, list or string of size `size`, and are in order.
`static void`	`checkState(boolean expression)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean expression, Object errorMessage)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, char p1)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, char p1, char p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, char p1, int p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, char p1, long p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, char p1, Object p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, int p1)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, int p1, char p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, int p1, int p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, int p1, long p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, int p1, Object p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, long p1)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, long p1, char p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, long p1, int p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, long p1, long p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, long p1, Object p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean expression, String errorMessageTemplate, Object... errorMessageArgs)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, Object p1)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, Object p1, char p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, Object p1, int p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, Object p1, long p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, Object p1, Object p2)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, Object p1, Object p2, Object p3)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.
`static void`	`checkState(boolean b, String errorMessageTemplate, Object p1, Object p2, Object p3, Object p4)` Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

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

Method Detail

checkArgument
```
public static void checkArgument(boolean expression)
```
Ensures the truth of an expression involving one or more parameters to the calling method.

Parameters:

expression - a boolean expression

Throws:

IllegalArgumentException - if expression is false

checkArgument
```
public static void checkArgument(boolean expression,
                                 @NullableDecl
                                 Object errorMessage)
```
Ensures the truth of an expression involving one or more parameters to the calling method.

Parameters:

expression - a boolean expression

errorMessage - the exception message to use if the check fails; will be converted to a string using String.valueOf(Object)

Throws:

IllegalArgumentException - if expression is false

checkArgument
```
public static void checkArgument(boolean expression,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 @NullableDecl
                                 Object... errorMessageArgs)
```
Ensures the truth of an expression involving one or more parameters to the calling method.

Parameters:

expression - a boolean expression

errorMessageTemplate - a template for the exception message should the check fail. The message is formed by replacing each %s placeholder in the template with an argument. These are matched by position - the first %s gets errorMessageArgs[0], etc. Unmatched arguments will be appended to the formatted message in square braces. Unmatched placeholders will be left as-is.

errorMessageArgs - the arguments to be substituted into the message template. Arguments are converted to strings using String.valueOf(Object).

Throws:

IllegalArgumentException - if expression is false

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 char p1)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 int p1)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 long p1)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 @NullableDecl
                                 Object p1)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 char p1,
                                 char p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 char p1,
                                 int p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 char p1,
                                 long p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 char p1,
                                 @NullableDecl
                                 Object p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 int p1,
                                 char p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 int p1,
                                 int p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 int p1,
                                 long p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 int p1,
                                 @NullableDecl
                                 Object p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 long p1,
                                 char p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 long p1,
                                 int p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 long p1,
                                 long p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 long p1,
                                 @NullableDecl
                                 Object p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 @NullableDecl
                                 Object p1,
                                 char p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 @NullableDecl
                                 Object p1,
                                 int p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 @NullableDecl
                                 Object p1,
                                 long p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 @NullableDecl
                                 Object p1,
                                 @NullableDecl
                                 Object p2)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 @NullableDecl
                                 Object p1,
                                 @NullableDecl
                                 Object p2,
                                 @NullableDecl
                                 Object p3)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkArgument

public static void checkArgument(boolean b,
                                 @NullableDecl
                                 String errorMessageTemplate,
                                 @NullableDecl
                                 Object p1,
                                 @NullableDecl
                                 Object p2,
                                 @NullableDecl
                                 Object p3,
                                 @NullableDecl
                                 Object p4)

Ensures the truth of an expression involving one or more parameters to the calling method.

See checkArgument(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState
```
public static void checkState(boolean expression)
```
Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

Parameters:

expression - a boolean expression

Throws:

IllegalStateException - if expression is false

See Also:

Verify.verify()

checkState
```
public static void checkState(boolean expression,
                              @NullableDecl
                              Object errorMessage)
```
Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

Parameters:

expression - a boolean expression

errorMessage - the exception message to use if the check fails; will be converted to a string using String.valueOf(Object)

Throws:

IllegalStateException - if expression is false

See Also:

Verify.verify()

checkState
```
public static void checkState(boolean expression,
                              @NullableDecl
                              String errorMessageTemplate,
                              @NullableDecl
                              Object... errorMessageArgs)
```
Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

Parameters:

expression - a boolean expression

errorMessageTemplate - a template for the exception message should the check fail. The message is formed by replacing each %s placeholder in the template with an argument. These are matched by position - the first %s gets errorMessageArgs[0], etc. Unmatched arguments will be appended to the formatted message in square braces. Unmatched placeholders will be left as-is.

errorMessageArgs - the arguments to be substituted into the message template. Arguments are converted to strings using String.valueOf(Object).

Throws:

IllegalStateException - if expression is false

See Also:

Verify.verify()

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              char p1)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              int p1)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              long p1)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              @NullableDecl
                              Object p1)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              char p1,
                              char p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              char p1,
                              int p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              char p1,
                              long p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              char p1,
                              @NullableDecl
                              Object p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              int p1,
                              char p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              int p1,
                              int p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              int p1,
                              long p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              int p1,
                              @NullableDecl
                              Object p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              long p1,
                              char p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              long p1,
                              int p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              long p1,
                              long p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              long p1,
                              @NullableDecl
                              Object p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              @NullableDecl
                              Object p1,
                              char p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              @NullableDecl
                              Object p1,
                              int p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              @NullableDecl
                              Object p1,
                              long p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              @NullableDecl
                              Object p1,
                              @NullableDecl
                              Object p2)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              @NullableDecl
                              Object p1,
                              @NullableDecl
                              Object p2,
                              @NullableDecl
                              Object p3)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkState

public static void checkState(boolean b,
                              @NullableDecl
                              String errorMessageTemplate,
                              @NullableDecl
                              Object p1,
                              @NullableDecl
                              Object p2,
                              @NullableDecl
                              Object p3,
                              @NullableDecl
                              Object p4)

Ensures the truth of an expression involving the state of the calling instance, but not involving any parameters to the calling method.

See checkState(boolean, String, Object...) for details.

Since:: 20.0 (varargs overload since 2.0)

checkNotNull
```
@CanIgnoreReturnValue
 @NonNullDecl
public static <T> T checkNotNull(@NonNullDecl
                                                                     T reference)
```
Ensures that an object reference passed as a parameter to the calling method is not null.

Parameters:

reference - an object reference

Returns:

the non-null reference that was validated

Throws:

NullPointerException - if reference is null

See Also:

Verify.verifyNotNull()