public class StringType extends NonNullFieldType<String>
String type. Null values are not supported by this class.
Strings are encoded as a sequence of characters followed by 0x00, where each character is encoded via
UnsignedIntEncoder, with the special exception that the characters 0x0000 and 0x0001
are prefixed with a 0x01 byte to avoid writing a 0x00. We rely on the fact that UnsignedIntEncoder
encodes 0 and 1 as 0x00 and 0x01, respectively.
name, NAME_PATTERN, REFERENCE_TYPE_NAME, signature, typeToken| Constructor and Description |
|---|
StringType() |
| Modifier and Type | Method and Description |
|---|---|
int |
compare(String string1,
String string2)
Order two field values.
|
<S> String |
convert(FieldType<S> type,
S value)
|
String |
fromParseableString(ParseContext ctx)
Parse a value previously encoded by
toParseableString() as a self-delimited String
and positioned at the start of the given parsing context. |
String |
fromString(String string)
Parse a non-null value previously encoded by
toString(T). |
boolean |
hasPrefix0xff()
Determine whether any of this field type's encoded values start with a
0xff byte. |
String |
read(ByteReader reader)
Read a value from the given input.
|
void |
skip(ByteReader reader)
Read and discard a value from the given input.
|
String |
toParseableString(String value)
Encode a possibly null value as a
String for later decoding by fromParseableString(). |
String |
toString(String value)
Encode a non-null value as a
String for later decoding by fromString(). |
void |
write(ByteWriter writer,
String value)
Write a value to the given output.
|
validateequals, genericizeForIndex, getDefaultValue, getDefaultValueObject, getEncodingSignature, getKeyRange, getName, getTypeToken, hashCode, hasPrefix0x00, toString, validateAndWriteclone, finalize, getClass, notify, notifyAll, wait, wait, waitcomparing, comparing, comparingDouble, comparingInt, comparingLong, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLongpublic String read(ByteReader reader)
FieldTypepublic void write(ByteWriter writer, String value)
FieldTypepublic void skip(ByteReader reader)
FieldTypepublic String toString(String value)
FieldTypeString for later decoding by fromString().
Each of the characters in the returned String must be one of the valid XML characters
(tab, newline, carriage return, \u0020 - \ud7ff, and \ue000 - \fffdf).
The implementation in FieldType checks that value is not null, then delegates to FieldType.toParseableString(T).
Subclasses that override this method should also override fromString().
toString in class FieldType<String>value - actual value, never nullvalue acceptable to fromString()public String fromString(String string)
FieldTypetoString(T).
The implementation in FieldType creates a new ParseContext based on string,
delegates to FieldType.toParseableString(T) to parse it, and verifies that all of string was consumed
during the parse. Subclasses that override this method should also override toString(T).
fromString in class FieldType<String>string - non-null value previously encoded as a String by toString(T)public String toParseableString(String value)
FieldTypeString for later decoding by fromParseableString().
The string value must be self-delimiting, i.e., decodable even when followed by arbitrary additional characters,
and must not start with whitespace or closing square bracket ("]").
In addition, each of the characters in the returned String must be one of the valid XML characters
(tab, newline, carriage return, \u0020 - \ud7ff, and \ue000 - \fffdf).
toParseableString in class FieldType<String>value - actual value (possibly null)value acceptable to fromParseableString()public String fromParseableString(ParseContext ctx)
FieldTypetoParseableString() as a self-delimited String
and positioned at the start of the given parsing context.fromParseableString in class FieldType<String>ctx - parse context starting with a string previously encoded via toParseableString()public boolean hasPrefix0xff()
FieldType0xff byte.
Certain optimizations are possible when this is not the case. It is safe for this method to always return true.
Note: changing the return value of this method usually means changing the binary encoding, resulting in an incompatible type.
The implementation in FieldType returns true.
hasPrefix0xff in class FieldType<String>0xff existspublic int compare(String string1, String string2)
FieldType
This method must provide a total ordering of all supported Java values that is consistent with the database ordering,
i.e., the unsigned lexicographical ordering of the corresponding byte[] encoded field values.
If null is a supported Java value, then the returned Comparator must accept null parameters without
throwing an exception (note, this is a stronger requirement than the Comparator interface normally requires).
Note: by convention, null values usually sort last.
public <S> String convert(FieldType<S> type, S value)
FieldTypeFieldType into a value of this FieldType.
For a non-null value, the implementation in FieldType first checks whether the value is already
a valid value for this type; if so, the value is returned. Otherwise, it invokes type.toString(value) to convert value into a String, and then attempts to parse that string via
this.fromString(); if the parse fails, an IllegalArgumentException is thrown.
If value is null, the implementation in FieldType returns null, unless this type does not support null
values, in which case an IllegalArgumentException is thrown.
Special handling also exists for certain conversions between built-in types:
value != 0char and a String of length one are convertible (other Strings are not)char[] array and a String are convertibleCopyright © 2020. All rights reserved.