Package feign

Class Util

  • public class Util
extends java.lang.Object
    Utilities, typically copied in from guava, so as to avoid dependency conflicts.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static java.lang.String CONTENT_ENCODING
      The HTTP Content-Encoding header field name.
      static java.lang.String CONTENT_LENGTH
      The HTTP Content-Length header field name.
      static java.lang.String ENCODING_DEFLATE
      Value for the Content-Encoding header that indicates that DEFLATE encoding is in use.
      static java.lang.String ENCODING_GZIP
      Value for the Content-Encoding header that indicates that GZIP encoding is in use.
      static java.nio.charset.Charset ISO_8859_1
      ISO-8859-1: ISO Latin Alphabet Number 1 (ISO-LATIN-1).
      static java.lang.reflect.Type MAP_STRING_WILDCARD
      Type literal for Map<String, ?>.
      static java.lang.String RETRY_AFTER
      The HTTP Retry-After header field name.
      static java.nio.charset.Charset UTF_8
      UTF-8: eight-bit UCS Transformation Format.

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static void checkArgument​(boolean expression, java.lang.String errorMessageTemplate, java.lang.Object... errorMessageArgs)
      Copy of com.google.common.base.Preconditions#checkArgument.
      static <T> T checkNotNull​(T reference, java.lang.String errorMessageTemplate, java.lang.Object... errorMessageArgs)
      Copy of com.google.common.base.Preconditions#checkNotNull.
      static void checkState​(boolean expression, java.lang.String errorMessageTemplate, java.lang.Object... errorMessageArgs)
      Copy of com.google.common.base.Preconditions#checkState.
      static java.lang.String decodeOrDefault​(byte[] data, java.nio.charset.Charset charset, java.lang.String defaultValue)  
      static java.lang.String emptyToNull​(java.lang.String string)
      Adapted from com.google.common.base.Strings#emptyToNull.
      static java.lang.Object emptyValueOf​(java.lang.reflect.Type type)
      This returns well known empty values for well-known java types.
      static void ensureClosed​(java.io.Closeable closeable)  
      static boolean isBlank​(java.lang.String value)
      If the provided String is null or empty.
      static boolean isDefault​(java.lang.reflect.Method method)
      Identifies a method as a default instance method.
      static boolean isNotBlank​(java.lang.String value)
      If the provided String is not null or empty.
      static <T> T[] removeValues​(T[] values, java.util.function.Predicate<T> shouldRemove, java.lang.Class<T> type)
      Removes values from the array that meet the criteria for removal via the supplied Predicate value
      static java.lang.reflect.Type resolveLastTypeParameter​(java.lang.reflect.Type genericContext, java.lang.Class<?> supertype)
      Resolves the last type parameter of the parameterized supertype, based on the genericContext, into its upper bounds.
      static <T> T[] toArray​(java.lang.Iterable<? extends T> iterable, java.lang.Class<T> type)
      Adapted from com.google.common.base.Strings#emptyToNull.
      static byte[] toByteArray​(java.io.InputStream in)
      Adapted from com.google.common.io.ByteStreams.toByteArray().
      static java.lang.String toString​(java.io.Reader reader)
      Adapted from com.google.common.io.CharStreams.toString().
      static <T> java.util.Collection<T> valuesOrEmpty​(java.util.Map<java.lang.String,​java.util.Collection<T>> map, java.lang.String key)
      Returns an unmodifiable collection which may be empty, but is never null.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • CONTENT_LENGTH

        public static final java.lang.String CONTENT_LENGTH
        The HTTP Content-Length header field name.
        See Also:
        Constant Field Values

      • CONTENT_ENCODING

        public static final java.lang.String CONTENT_ENCODING
        The HTTP Content-Encoding header field name.
        See Also:
        Constant Field Values

      • RETRY_AFTER

        public static final java.lang.String RETRY_AFTER
        The HTTP Retry-After header field name.
        See Also:
        Constant Field Values

      • ENCODING_GZIP

        public static final java.lang.String ENCODING_GZIP
        Value for the Content-Encoding header that indicates that GZIP encoding is in use.
        See Also:
        Constant Field Values

      • ENCODING_DEFLATE

        public static final java.lang.String ENCODING_DEFLATE
        Value for the Content-Encoding header that indicates that DEFLATE encoding is in use.
        See Also:
        Constant Field Values

      • UTF_8

        public static final java.nio.charset.Charset UTF_8
        UTF-8: eight-bit UCS Transformation Format.

      • ISO_8859_1

        public static final java.nio.charset.Charset ISO_8859_1
        ISO-8859-1: ISO Latin Alphabet Number 1 (ISO-LATIN-1).

      • MAP_STRING_WILDCARD

        public static final java.lang.reflect.Type MAP_STRING_WILDCARD
        Type literal for Map<String, ?>.

    • Method Detail

      • checkArgument

        public static void checkArgument​(boolean expression,
                                 java.lang.String errorMessageTemplate,
                                 java.lang.Object... errorMessageArgs)
        Copy of com.google.common.base.Preconditions#checkArgument.

      • checkNotNull

        public static <T> T checkNotNull​(T reference,
                                 java.lang.String errorMessageTemplate,
                                 java.lang.Object... errorMessageArgs)
        Copy of com.google.common.base.Preconditions#checkNotNull.

      • checkState

        public static void checkState​(boolean expression,
                              java.lang.String errorMessageTemplate,
                              java.lang.Object... errorMessageArgs)
        Copy of com.google.common.base.Preconditions#checkState.

      • isDefault

        public static boolean isDefault​(java.lang.reflect.Method method)
        Identifies a method as a default instance method.

      • emptyToNull

        public static java.lang.String emptyToNull​(java.lang.String string)
        Adapted from com.google.common.base.Strings#emptyToNull.

      • removeValues

        public static <T> T[] removeValues​(T[] values,
                                   java.util.function.Predicate<T> shouldRemove,
                                   java.lang.Class<T> type)
        Removes values from the array that meet the criteria for removal via the supplied Predicate value

      • toArray

        public static <T> T[] toArray​(java.lang.Iterable<? extends T> iterable,
                              java.lang.Class<T> type)
        Adapted from com.google.common.base.Strings#emptyToNull.

      • valuesOrEmpty

        public static <T> java.util.Collection<T> valuesOrEmpty​(java.util.Map<java.lang.String,​java.util.Collection<T>> map,
                                                        java.lang.String key)
        Returns an unmodifiable collection which may be empty, but is never null.

      • ensureClosed

        public static void ensureClosed​(java.io.Closeable closeable)

      • resolveLastTypeParameter

        public static java.lang.reflect.Type resolveLastTypeParameter​(java.lang.reflect.Type genericContext,
                                                              java.lang.Class<?> supertype)
                                                       throws java.lang.IllegalStateException
        Resolves the last type parameter of the parameterized supertype, based on the genericContext, into its upper bounds.

        Implementation copied from retrofit.RestMethodInfo.

        Parameters:
        genericContext - Ex. Field.getGenericType()
        supertype - Ex. Decoder.class
        Returns:
        in the example above, the type parameter of Decoder.
        Throws:
        java.lang.IllegalStateException - if supertype cannot be resolved into a parameterized type using context.

      • emptyValueOf

        public static java.lang.Object emptyValueOf​(java.lang.reflect.Type type)
        This returns well known empty values for well-known java types. This returns null for types not in the following list.
        • [Bb]oolean
        • byte[]
        • Collection
        • Iterator
        • List
        • Map
        • Set

        When decoding HTTP 404 status, you'll need to teach decoders a default empty value for a type. This method cheaply supports typical types by only looking at the raw type (vs type hierarchy). Decorate for sophistication.

      • toString

        public static java.lang.String toString​(java.io.Reader reader)
                                 throws java.io.IOException
        Adapted from com.google.common.io.CharStreams.toString().
        Throws:
        java.io.IOException

      • toByteArray

        public static byte[] toByteArray​(java.io.InputStream in)
                          throws java.io.IOException
        Adapted from com.google.common.io.ByteStreams.toByteArray().
        Throws:
        java.io.IOException

      • decodeOrDefault

        public static java.lang.String decodeOrDefault​(byte[] data,
                                               java.nio.charset.Charset charset,
                                               java.lang.String defaultValue)

      • isNotBlank

        public static boolean isNotBlank​(java.lang.String value)
        If the provided String is not null or empty.
        Parameters:
        value - to evaluate.
        Returns:
        true of the value is not null and not empty.

      • isBlank

        public static boolean isBlank​(java.lang.String value)
        If the provided String is null or empty.
        Parameters:
        value - to evaluate.
        Returns:
        true if the value is null or empty.