feign

Class Util

java.lang.Object

feign.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 and 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.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

Methods

Modifier and Type	Method and 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	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 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).

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.

emptyToNull

public static java.lang.String emptyToNull(java.lang.String string)

Adapted from com.google.common.base.Strings#emptyToNull.

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