All Downloads are FREE. Search and download functionalities are using the official Maven repository.

gwtrpc.shaded.com.google.common.base.Preconditions Maven / Gradle / Ivy

There is a newer version: 1.0-alpha-8
Show newest version
/*
 * Copyright (C) 2007 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.base;

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import javax.annotation.Nullable;

/**
 * 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 {@code 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 * *

{@code
 * 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 * *

{@code
 * 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: * *

{@code
 *   void exampleBadCaller() {
 *     double d = sqrt(-1.0);
 * }
 * }
* *

would be flagged as having called {@code 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 {@link java.util.NoSuchElementException} or {@link * 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, {@link Verify} offers assertions * similar to those in this class for non-precondition checks. * *

{@code java.util.Objects.requireNonNull()}

* *

Projects which use {@code com.google.common} should generally avoid the use of {@link * java.util.Objects#requireNonNull(Object)}. Instead, use whichever of {@link * #checkNotNull(Object)} or {@link Verify#verifyNotNull(Object)} is appropriate to the situation. * (The same goes for the message-accepting overloads.) * *

Only {@code %s} is supported

* *

In {@code Preconditions} error message template strings, only the {@code "%s"} specifier is * supported, not the full range of {@link java.util.Formatter} specifiers. * *

More information

* *

See the Guava User Guide on using {@code * Preconditions}. * * @author Kevin Bourrillion * @since 2.0 */ @GwtCompatible public final class Preconditions { private Preconditions() {} /** * Ensures the truth of an expression involving one or more parameters to the calling method. * * @param expression a boolean expression * @throws IllegalArgumentException if {@code expression} is false */ public static void checkArgument(boolean expression) { if (!expression) { throw new IllegalArgumentException(); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * * @param expression a boolean expression * @param errorMessage the exception message to use if the check fails; will be converted to a * string using {@link String#valueOf(Object)} * @throws IllegalArgumentException if {@code expression} is false */ public static void checkArgument(boolean expression, @Nullable Object errorMessage) { if (!expression) { throw new IllegalArgumentException(String.valueOf(errorMessage)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * * @param expression a boolean expression * @param errorMessageTemplate a template for the exception message should the check fail. The * message is formed by replacing each {@code %s} placeholder in the template with an * argument. These are matched by position - the first {@code %s} gets {@code * errorMessageArgs[0]}, etc. Unmatched arguments will be appended to the formatted message in * square braces. Unmatched placeholders will be left as-is. * @param errorMessageArgs the arguments to be substituted into the message template. Arguments * are converted to strings using {@link String#valueOf(Object)}. * @throws IllegalArgumentException if {@code expression} is false */ public static void checkArgument( boolean expression, @Nullable String errorMessageTemplate, @Nullable Object... errorMessageArgs) { if (!expression) { throw new IllegalArgumentException(format(errorMessageTemplate, errorMessageArgs)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument(boolean b, @Nullable String errorMessageTemplate, char p1) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument(boolean b, @Nullable String errorMessageTemplate, int p1) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument(boolean b, @Nullable String errorMessageTemplate, long p1) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, char p1, char p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, char p1, int p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, char p1, long p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, char p1, @Nullable Object p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, int p1, char p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, int p1, int p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, int p1, long p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, int p1, @Nullable Object p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, long p1, char p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, long p1, int p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, long p1, long p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, long p1, @Nullable Object p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, char p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, int p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, long p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, @Nullable Object p2) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, @Nullable Object p2, @Nullable Object p3) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2, p3)); } } /** * Ensures the truth of an expression involving one or more parameters to the calling method. * *

See {@link #checkArgument(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkArgument( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, @Nullable Object p2, @Nullable Object p3, @Nullable Object p4) { if (!b) { throw new IllegalArgumentException(format(errorMessageTemplate, p1, p2, p3, p4)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * * @param expression a boolean expression * @throws IllegalStateException if {@code expression} is false * @see Verify#verify Verify.verify() */ public static void checkState(boolean expression) { if (!expression) { throw new IllegalStateException(); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * * @param expression a boolean expression * @param errorMessage the exception message to use if the check fails; will be converted to a * string using {@link String#valueOf(Object)} * @throws IllegalStateException if {@code expression} is false * @see Verify#verify Verify.verify() */ public static void checkState(boolean expression, @Nullable Object errorMessage) { if (!expression) { throw new IllegalStateException(String.valueOf(errorMessage)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * * @param expression a boolean expression * @param errorMessageTemplate a template for the exception message should the check fail. The * message is formed by replacing each {@code %s} placeholder in the template with an * argument. These are matched by position - the first {@code %s} gets {@code * errorMessageArgs[0]}, etc. Unmatched arguments will be appended to the formatted message in * square braces. Unmatched placeholders will be left as-is. * @param errorMessageArgs the arguments to be substituted into the message template. Arguments * are converted to strings using {@link String#valueOf(Object)}. * @throws IllegalStateException if {@code expression} is false * @see Verify#verify Verify.verify() */ public static void checkState( boolean expression, @Nullable String errorMessageTemplate, @Nullable Object... errorMessageArgs) { if (!expression) { throw new IllegalStateException(format(errorMessageTemplate, errorMessageArgs)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState(boolean b, @Nullable String errorMessageTemplate, char p1) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState(boolean b, @Nullable String errorMessageTemplate, int p1) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState(boolean b, @Nullable String errorMessageTemplate, long p1) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, char p1, char p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState(boolean b, @Nullable String errorMessageTemplate, char p1, int p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, char p1, long p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, char p1, @Nullable Object p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState(boolean b, @Nullable String errorMessageTemplate, int p1, char p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState(boolean b, @Nullable String errorMessageTemplate, int p1, int p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState(boolean b, @Nullable String errorMessageTemplate, int p1, long p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, int p1, @Nullable Object p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, long p1, char p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState(boolean b, @Nullable String errorMessageTemplate, long p1, int p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, long p1, long p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, long p1, @Nullable Object p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, char p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, int p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, long p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, @Nullable Object p2) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, @Nullable Object p2, @Nullable Object p3) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2, p3)); } } /** * Ensures the truth of an expression involving the state of the calling instance, but not * involving any parameters to the calling method. * *

See {@link #checkState(boolean, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ public static void checkState( boolean b, @Nullable String errorMessageTemplate, @Nullable Object p1, @Nullable Object p2, @Nullable Object p3, @Nullable Object p4) { if (!b) { throw new IllegalStateException(format(errorMessageTemplate, p1, p2, p3, p4)); } } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * * @param reference an object reference * @return the non-null reference that was validated * @throws NullPointerException if {@code reference} is null * @see Verify#verifyNotNull Verify.verifyNotNull() */ @CanIgnoreReturnValue public static T checkNotNull(T reference) { if (reference == null) { throw new NullPointerException(); } return reference; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * * @param reference an object reference * @param errorMessage the exception message to use if the check fails; will be converted to a * string using {@link String#valueOf(Object)} * @return the non-null reference that was validated * @throws NullPointerException if {@code reference} is null * @see Verify#verifyNotNull Verify.verifyNotNull() */ @CanIgnoreReturnValue public static T checkNotNull(T reference, @Nullable Object errorMessage) { if (reference == null) { throw new NullPointerException(String.valueOf(errorMessage)); } return reference; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * * @param reference an object reference * @param errorMessageTemplate a template for the exception message should the check fail. The * message is formed by replacing each {@code %s} placeholder in the template with an * argument. These are matched by position - the first {@code %s} gets {@code * errorMessageArgs[0]}, etc. Unmatched arguments will be appended to the formatted message in * square braces. Unmatched placeholders will be left as-is. * @param errorMessageArgs the arguments to be substituted into the message template. Arguments * are converted to strings using {@link String#valueOf(Object)}. * @return the non-null reference that was validated * @throws NullPointerException if {@code reference} is null * @see Verify#verifyNotNull Verify.verifyNotNull() */ @CanIgnoreReturnValue public static T checkNotNull( T reference, @Nullable String errorMessageTemplate, @Nullable Object... errorMessageArgs) { if (reference == null) { throw new NullPointerException(format(errorMessageTemplate, errorMessageArgs)); } return reference; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull(T obj, @Nullable String errorMessageTemplate, char p1) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull(T obj, @Nullable String errorMessageTemplate, int p1) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull(T obj, @Nullable String errorMessageTemplate, long p1) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull( T obj, @Nullable String errorMessageTemplate, @Nullable Object p1) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull(T obj, @Nullable String errorMessageTemplate, char p1, char p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull(T obj, @Nullable String errorMessageTemplate, char p1, int p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull(T obj, @Nullable String errorMessageTemplate, char p1, long p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull( T obj, @Nullable String errorMessageTemplate, char p1, @Nullable Object p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull(T obj, @Nullable String errorMessageTemplate, int p1, char p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull(T obj, @Nullable String errorMessageTemplate, int p1, int p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull(T obj, @Nullable String errorMessageTemplate, int p1, long p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull( T obj, @Nullable String errorMessageTemplate, int p1, @Nullable Object p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull(T obj, @Nullable String errorMessageTemplate, long p1, char p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull(T obj, @Nullable String errorMessageTemplate, long p1, int p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull(T obj, @Nullable String errorMessageTemplate, long p1, long p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull( T obj, @Nullable String errorMessageTemplate, long p1, @Nullable Object p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull( T obj, @Nullable String errorMessageTemplate, @Nullable Object p1, char p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull( T obj, @Nullable String errorMessageTemplate, @Nullable Object p1, int p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull( T obj, @Nullable String errorMessageTemplate, @Nullable Object p1, long p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull( T obj, @Nullable String errorMessageTemplate, @Nullable Object p1, @Nullable Object p2) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull( T obj, @Nullable String errorMessageTemplate, @Nullable Object p1, @Nullable Object p2, @Nullable Object p3) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2, p3)); } return obj; } /** * Ensures that an object reference passed as a parameter to the calling method is not null. * *

See {@link #checkNotNull(Object, String, Object...)} for details. * * @since 20.0 (varargs overload since 2.0) */ @CanIgnoreReturnValue public static T checkNotNull( T obj, @Nullable String errorMessageTemplate, @Nullable Object p1, @Nullable Object p2, @Nullable Object p3, @Nullable Object p4) { if (obj == null) { throw new NullPointerException(format(errorMessageTemplate, p1, p2, p3, p4)); } return obj; } /* * All recent hotspots (as of 2009) *really* like to have the natural code * * if (guardExpression) { * throw new BadException(messageExpression); * } * * refactored so that messageExpression is moved to a separate String-returning method. * * if (guardExpression) { * throw new BadException(badMsg(...)); * } * * The alternative natural refactorings into void or Exception-returning methods are much slower. * This is a big deal - we're talking factors of 2-8 in microbenchmarks, not just 10-20%. (This is * a hotspot optimizer bug, which should be fixed, but that's a separate, big project). * * The coding pattern above is heavily used in java.util, e.g. in ArrayList. There is a * RangeCheckMicroBenchmark in the JDK that was used to test this. * * But the methods in this class want to throw different exceptions, depending on the args, so it * appears that this pattern is not directly applicable. But we can use the ridiculous, devious * trick of throwing an exception in the middle of the construction of another exception. Hotspot * is fine with that. */ /** * Ensures that {@code index} specifies a valid element in an array, list or string of size * {@code size}. An element index may range from zero, inclusive, to {@code size}, exclusive. * * @param index a user-supplied index identifying an element of an array, list or string * @param size the size of that array, list or string * @return the value of {@code index} * @throws IndexOutOfBoundsException if {@code index} is negative or is not less than {@code size} * @throws IllegalArgumentException if {@code size} is negative */ @CanIgnoreReturnValue public static int checkElementIndex(int index, int size) { return checkElementIndex(index, size, "index"); } /** * Ensures that {@code index} specifies a valid element in an array, list or string of size * {@code size}. An element index may range from zero, inclusive, to {@code size}, exclusive. * * @param index a user-supplied index identifying an element of an array, list or string * @param size the size of that array, list or string * @param desc the text to use to describe this index in an error message * @return the value of {@code index} * @throws IndexOutOfBoundsException if {@code index} is negative or is not less than {@code size} * @throws IllegalArgumentException if {@code size} is negative */ @CanIgnoreReturnValue public static int checkElementIndex(int index, int size, @Nullable String desc) { // Carefully optimized for execution by hotspot (explanatory comment above) if (index < 0 || index >= size) { throw new IndexOutOfBoundsException(badElementIndex(index, size, desc)); } return index; } private static String badElementIndex(int index, int size, String desc) { if (index < 0) { return format("%s (%s) must not be negative", desc, index); } else if (size < 0) { throw new IllegalArgumentException("negative size: " + size); } else { // index >= size return format("%s (%s) must be less than size (%s)", desc, index, size); } } /** * Ensures that {@code index} specifies a valid position in an array, list or string of * size {@code size}. A position index may range from zero to {@code size}, inclusive. * * @param index a user-supplied index identifying a position in an array, list or string * @param size the size of that array, list or string * @return the value of {@code index} * @throws IndexOutOfBoundsException if {@code index} is negative or is greater than {@code size} * @throws IllegalArgumentException if {@code size} is negative */ @CanIgnoreReturnValue public static int checkPositionIndex(int index, int size) { return checkPositionIndex(index, size, "index"); } /** * Ensures that {@code index} specifies a valid position in an array, list or string of * size {@code size}. A position index may range from zero to {@code size}, inclusive. * * @param index a user-supplied index identifying a position in an array, list or string * @param size the size of that array, list or string * @param desc the text to use to describe this index in an error message * @return the value of {@code index} * @throws IndexOutOfBoundsException if {@code index} is negative or is greater than {@code size} * @throws IllegalArgumentException if {@code size} is negative */ @CanIgnoreReturnValue public static int checkPositionIndex(int index, int size, @Nullable String desc) { // Carefully optimized for execution by hotspot (explanatory comment above) if (index < 0 || index > size) { throw new IndexOutOfBoundsException(badPositionIndex(index, size, desc)); } return index; } private static String badPositionIndex(int index, int size, String desc) { if (index < 0) { return format("%s (%s) must not be negative", desc, index); } else if (size < 0) { throw new IllegalArgumentException("negative size: " + size); } else { // index > size return format("%s (%s) must not be greater than size (%s)", desc, index, size); } } /** * Ensures that {@code start} and {@code end} specify a valid positions in an array, list * or string of size {@code size}, and are in order. A position index may range from zero to * {@code size}, inclusive. * * @param start a user-supplied index identifying a starting position in an array, list or string * @param end a user-supplied index identifying a ending position in an array, list or string * @param size the size of that array, list or string * @throws IndexOutOfBoundsException if either index is negative or is greater than {@code size}, * or if {@code end} is less than {@code start} * @throws IllegalArgumentException if {@code size} is negative */ public static void checkPositionIndexes(int start, int end, int size) { // Carefully optimized for execution by hotspot (explanatory comment above) if (start < 0 || end < start || end > size) { throw new IndexOutOfBoundsException(badPositionIndexes(start, end, size)); } } private static String badPositionIndexes(int start, int end, int size) { if (start < 0 || start > size) { return badPositionIndex(start, size, "start index"); } if (end < 0 || end > size) { return badPositionIndex(end, size, "end index"); } // end < start return format("end index (%s) must not be less than start index (%s)", end, start); } /** * Substitutes each {@code %s} in {@code template} with an argument. These are matched by * position: the first {@code %s} gets {@code args[0]}, etc. If there are more arguments than * placeholders, the unmatched arguments will be appended to the end of the formatted message in * square braces. * * @param template a string containing 0 or more {@code %s} placeholders. null is treated as * "null". * @param args the arguments to be substituted into the message template. Arguments are converted * to strings using {@link String#valueOf(Object)}. Arguments can be null. */ // Note that this is somewhat-improperly used from Verify.java as well. static String format(@Nullable String template, @Nullable Object... args) { template = String.valueOf(template); // null -> "null" args = args == null ? new Object[]{"(Object[])null"} : args; // start substituting the arguments into the '%s' placeholders StringBuilder builder = new StringBuilder(template.length() + 16 * args.length); int templateStart = 0; int i = 0; while (i < args.length) { int placeholderStart = template.indexOf("%s", templateStart); if (placeholderStart == -1) { break; } builder.append(template, templateStart, placeholderStart); builder.append(args[i++]); templateStart = placeholderStart + 2; } builder.append(template, templateStart, template.length()); // if we run out of placeholders, append the extra args in square braces if (i < args.length) { builder.append(" ["); builder.append(args[i++]); while (i < args.length) { builder.append(", "); builder.append(args[i++]); } builder.append(']'); } return builder.toString(); } }





© 2015 - 2024 Weber Informatics LLC | Privacy Policy