Class Utils

java.lang.Object
io.opencensus.internal.Utils
public final class Utils extends Object
General internal utility methods.

  • Constructor Details

    • Utils

      private Utils()

  • Method Details

    • checkArgument

      public static void checkArgument(boolean isValid, @Nullable Object errorMessage)
      Throws an IllegalArgumentException if the argument is false. This method is similar to Preconditions.checkArgument(boolean, Object) from Guava.
      Parameters:
      isValid - whether the argument check passed.
      errorMessage - the message to use for the exception. Will be converted to a string using String.valueOf(Object).

    • checkArgument

      public static void checkArgument(boolean expression, String errorMessageTemplate, @Nullable Object... errorMessageArgs)
      Throws an IllegalArgumentException if the argument is false. This method is similar to Preconditions.checkArgument(boolean, Object) from Guava.
      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
      NullPointerException - if the check fails and either errorMessageTemplate or errorMessageArgs is null (don't let this happen)

    • checkState

      public static void checkState(boolean isValid, @Nullable Object errorMessage)
      Throws an IllegalStateException if the argument is false. This method is similar to Preconditions.checkState(boolean, Object) from Guava.
      Parameters:
      isValid - whether the state check passed.
      errorMessage - the message to use for the exception. Will be converted to a string using String.valueOf(Object).

    • checkIndex

      public static void checkIndex(int index, int size)
      Validates an index in an array or other container. This method throws an IllegalArgumentException if the size is negative and throws an IndexOutOfBoundsException if the index is negative or greater than or equal to the size. This method is similar to Preconditions.checkElementIndex(int, int) from Guava.
      Parameters:
      index - the index to validate.
      size - the size of the array or container.

    • checkNotNull

      public static <T> T checkNotNull(T arg, @Nullable Object errorMessage)
      Throws a NullPointerException if the argument is null. This method is similar to Preconditions.checkNotNull(Object, Object) from Guava.
      Parameters:
      arg - the argument to check for null.
      errorMessage - the message to use for the exception. Will be converted to a string using String.valueOf(Object).
      Returns:
      the argument, if it passes the null check.

    • checkListElementNotNull

      public static <T> void checkListElementNotNull(List<T> list, @Nullable Object errorMessage)
      Throws a NullPointerException if any of the list elements is null.
      Parameters:
      list - the argument list to check for null.
      errorMessage - the message to use for the exception. Will be converted to a string using String.valueOf(Object).

    • checkMapElementNotNull

      public static <K,V> void checkMapElementNotNull(Map<K,V> map, @Nullable Object errorMessage)
      Throws a NullPointerException if any of the map elements is null.
      Parameters:
      map - the argument map to check for null.
      errorMessage - the message to use for the exception. Will be converted to a string using String.valueOf(Object).

    • equalsObjects

      public static boolean equalsObjects(@Nullable Object x, @Nullable Object y)
      Compares two Objects for equality. This functionality is provided by Objects.equal(Object, Object) in Java 7.

    • format

      private static String format(String template, @Nullable Object... args)
      Substitutes each %s in template with an argument. These are matched by position: the first %s gets 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.

      Copied from Preconditions.format(String, Object...) from Guava

      Parameters:
      template - a non-null string containing 0 or more %s placeholders.
      args - the arguments to be substituted into the message template. Arguments are converted to strings using String.valueOf(Object). Arguments can be null.