| Package | Description | 
|---|---|
| java.io | Provides for system input and output through data streams,
serialization and the file system. | 
| java.lang | Provides classes that are fundamental to the design of the Java
 programming language. | 
| java.nio | Defines buffers, which are containers for data, and provides an overview of the
other NIO packages. | 
| java.nio.charset | Defines charsets, decoders, and encoders, for translating between bytes and
Unicode characters. | 
| java.nio.file | Defines interfaces and classes for the Java virtual machine to access files,
 file attributes, and file systems. | 
| java.text | Provides classes and interfaces for handling text, dates, numbers, and messages
in a manner independent of natural languages. | 
| java.time | 
 The main API for dates, times, instants, and durations. | 
| java.time.format | 
 Provides classes to print and parse dates and times. | 
| java.util | Contains the collections framework, legacy collection classes, event model,
date and time facilities, internationalization, and miscellaneous utility
classes (a string tokenizer, a random-number generator, and a bit array). | 
| java.util.regex | Classes for matching character sequences against patterns specified by regular
expressions. | 
| java.util.stream | Classes to support functional-style operations on streams of elements, such
 as map-reduce transformations on collections. | 
| javax.annotation.processing | Facilities for declaring annotation processors and for
 allowing annotation processors to communicate with an annotation processing
 tool environment. | 
| javax.lang.model | Classes and hierarchies of packages used to model the Java
 programming language. | 
| javax.lang.model.element | Interfaces used to model elements of the Java programming language. | 
| javax.lang.model.util | Utilities to assist in the processing of
 program elements and
 types. | 
| javax.swing.text | Provides classes and interfaces that deal with editable
and noneditable text components. | 
| javax.tools | Provides interfaces for tools which can be invoked from a program,
 for example, compilers. | 
| Modifier and Type | Method and Description | 
|---|---|
| StringWriter | StringWriter. append(CharSequence csq)Appends the specified character sequence to this writer. | 
| CharArrayWriter | CharArrayWriter. append(CharSequence csq)Appends the specified character sequence to this writer. | 
| Writer | Writer. append(CharSequence csq)Appends the specified character sequence to this writer. | 
| PrintWriter | PrintWriter. append(CharSequence csq)Appends the specified character sequence to this writer. | 
| PrintStream | PrintStream. append(CharSequence csq)Appends the specified character sequence to this output stream. | 
| StringWriter | StringWriter. append(CharSequence csq,
      int start,
      int end)Appends a subsequence of the specified character sequence to this writer. | 
| CharArrayWriter | CharArrayWriter. append(CharSequence csq,
      int start,
      int end)Appends a subsequence of the specified character sequence to this writer. | 
| Writer | Writer. append(CharSequence csq,
      int start,
      int end)Appends a subsequence of the specified character sequence to this writer. | 
| PrintWriter | PrintWriter. append(CharSequence csq,
      int start,
      int end)Appends a subsequence of the specified character sequence to this writer. | 
| PrintStream | PrintStream. append(CharSequence csq,
      int start,
      int end)Appends a subsequence of the specified character sequence to this output
 stream. | 
| Modifier and Type | Class and Description | 
|---|---|
| class  | StringThe  Stringclass represents character strings. | 
| class  | StringBufferA thread-safe, mutable sequence of characters. | 
| class  | StringBuilderA mutable sequence of characters. | 
| Modifier and Type | Method and Description | 
|---|---|
| CharSequence | StringBuffer. subSequence(int start,
           int end) | 
| CharSequence | CharSequence. subSequence(int start,
           int end)Returns a  CharSequencethat is a subsequence of this sequence. | 
| CharSequence | String. subSequence(int beginIndex,
           int endIndex)Returns a character sequence that is a subsequence of this sequence. | 
| Modifier and Type | Method and Description | 
|---|---|
| StringBuffer | StringBuffer. append(CharSequence s)Appends the specified  CharSequenceto this
 sequence. | 
| Appendable | Appendable. append(CharSequence csq)Appends the specified character sequence to this Appendable. | 
| StringBuilder | StringBuilder. append(CharSequence s) | 
| StringBuffer | StringBuffer. append(CharSequence s,
      int start,
      int end) | 
| Appendable | Appendable. append(CharSequence csq,
      int start,
      int end)Appends a subsequence of the specified character sequence to this
 Appendable. | 
| StringBuilder | StringBuilder. append(CharSequence s,
      int start,
      int end) | 
| static int | Character. codePointAt(CharSequence seq,
           int index)Returns the code point at the given index of the
  CharSequence. | 
| static int | Character. codePointBefore(CharSequence seq,
               int index)Returns the code point preceding the given index of the
  CharSequence. | 
| static int | Character. codePointCount(CharSequence seq,
              int beginIndex,
              int endIndex)Returns the number of Unicode code points in the text range of
 the specified char sequence. | 
| boolean | String. contains(CharSequence s)Returns true if and only if this string contains the specified
 sequence of char values. | 
| boolean | String. contentEquals(CharSequence cs)Compares this string to the specified  CharSequence. | 
| StringBuffer | StringBuffer. insert(int dstOffset,
      CharSequence s) | 
| StringBuilder | StringBuilder. insert(int dstOffset,
      CharSequence s) | 
| StringBuffer | StringBuffer. insert(int dstOffset,
      CharSequence s,
      int start,
      int end) | 
| StringBuilder | StringBuilder. insert(int dstOffset,
      CharSequence s,
      int start,
      int end) | 
| static String | String. join(CharSequence delimiter,
    CharSequence... elements)Returns a new String composed of copies of the
  CharSequence elementsjoined together with a copy of
 the specifieddelimiter. | 
| static String | String. join(CharSequence delimiter,
    CharSequence... elements)Returns a new String composed of copies of the
  CharSequence elementsjoined together with a copy of
 the specifieddelimiter. | 
| static String | String. join(CharSequence delimiter,
    Iterable<? extends CharSequence> elements)Returns a new  Stringcomposed of copies of theCharSequence elementsjoined together with a copy of the
 specifieddelimiter. | 
| static int | Character. offsetByCodePoints(CharSequence seq,
                  int index,
                  int codePointOffset)Returns the index within the given char sequence that is offset
 from the given  indexbycodePointOffsetcode points. | 
| String | String. replace(CharSequence target,
       CharSequence replacement)Replaces each substring of this string that matches the literal target
 sequence with the specified literal replacement sequence. | 
| Modifier and Type | Method and Description | 
|---|---|
| static String | String. join(CharSequence delimiter,
    Iterable<? extends CharSequence> elements)Returns a new  Stringcomposed of copies of theCharSequence elementsjoined together with a copy of the
 specifieddelimiter. | 
| Constructor and Description | 
|---|
| StringBuffer(CharSequence seq)Constructs a string buffer that contains the same characters
 as the specified  CharSequence. | 
| StringBuilder(CharSequence seq)Constructs a string builder that contains the same characters
 as the specified  CharSequence. | 
| Modifier and Type | Class and Description | 
|---|---|
| class  | CharBufferA char buffer. | 
| Modifier and Type | Method and Description | 
|---|---|
| CharBuffer | CharBuffer. append(CharSequence csq)Appends the specified character sequence  to this
 buffer  (optional operation). | 
| CharBuffer | CharBuffer. append(CharSequence csq,
      int start,
      int end)Appends a subsequence of the  specified character sequence  to this
 buffer  (optional operation). | 
| static CharBuffer | CharBuffer. wrap(CharSequence csq)Wraps a character sequence into a buffer. | 
| static CharBuffer | CharBuffer. wrap(CharSequence csq,
    int start,
    int end)Wraps a character sequence into a buffer. | 
| Modifier and Type | Method and Description | 
|---|---|
| boolean | CharsetEncoder. canEncode(CharSequence cs)Tells whether or not this encoder can encode the given character
 sequence. | 
| Modifier and Type | Method and Description | 
|---|---|
| static Path | Files. write(Path path,
     Iterable<? extends CharSequence> lines,
     Charset cs,
     OpenOption... options)Write lines of text to a file. | 
| static Path | Files. write(Path path,
     Iterable<? extends CharSequence> lines,
     OpenOption... options)Write lines of text to a file. | 
| Modifier and Type | Method and Description | 
|---|---|
| static boolean | Normalizer. isNormalized(CharSequence src,
            Normalizer.Form form)Determines if the given sequence of char values is normalized. | 
| static String | Normalizer. normalize(CharSequence src,
         Normalizer.Form form)Normalize a sequence of char values. | 
| Modifier and Type | Method and Description | 
|---|---|
| static YearMonth | YearMonth. parse(CharSequence text)Obtains an instance of  YearMonthfrom a text string such as2007-12. | 
| static Year | Year. parse(CharSequence text)Obtains an instance of  Yearfrom a text string such as2007. | 
| static MonthDay | MonthDay. parse(CharSequence text)Obtains an instance of  MonthDayfrom a text string such as--12-03. | 
| static Period | Period. parse(CharSequence text)Obtains a  Periodfrom a text string such asPnYnMnD. | 
| static Duration | Duration. parse(CharSequence text)Obtains a  Durationfrom a text string such asPnDTnHnMn.nS. | 
| static OffsetTime | OffsetTime. parse(CharSequence text)Obtains an instance of  OffsetTimefrom a text string such as10:15:30+01:00. | 
| static LocalDateTime | LocalDateTime. parse(CharSequence text)Obtains an instance of  LocalDateTimefrom a text string such as2007-12-03T10:15:30. | 
| static LocalDate | LocalDate. parse(CharSequence text)Obtains an instance of  LocalDatefrom a text string such as2007-12-03. | 
| static ZonedDateTime | ZonedDateTime. parse(CharSequence text)Obtains an instance of  ZonedDateTimefrom a text string such as2007-12-03T10:15:30+01:00[Europe/Paris]. | 
| static OffsetDateTime | OffsetDateTime. parse(CharSequence text)Obtains an instance of  OffsetDateTimefrom a text string
 such as2007-12-03T10:15:30+01:00. | 
| static Instant | Instant. parse(CharSequence text)Obtains an instance of  Instantfrom a text string such as2007-12-03T10:15:30.00Z. | 
| static LocalTime | LocalTime. parse(CharSequence text)Obtains an instance of  LocalTimefrom a text string such as10:15. | 
| static YearMonth | YearMonth. parse(CharSequence text,
     DateTimeFormatter formatter)Obtains an instance of  YearMonthfrom a text string using a specific formatter. | 
| static Year | Year. parse(CharSequence text,
     DateTimeFormatter formatter)Obtains an instance of  Yearfrom a text string using a specific formatter. | 
| static MonthDay | MonthDay. parse(CharSequence text,
     DateTimeFormatter formatter)Obtains an instance of  MonthDayfrom a text string using a specific formatter. | 
| static OffsetTime | OffsetTime. parse(CharSequence text,
     DateTimeFormatter formatter)Obtains an instance of  OffsetTimefrom a text string using a specific formatter. | 
| static LocalDateTime | LocalDateTime. parse(CharSequence text,
     DateTimeFormatter formatter)Obtains an instance of  LocalDateTimefrom a text string using a specific formatter. | 
| static LocalDate | LocalDate. parse(CharSequence text,
     DateTimeFormatter formatter)Obtains an instance of  LocalDatefrom a text string using a specific formatter. | 
| static ZonedDateTime | ZonedDateTime. parse(CharSequence text,
     DateTimeFormatter formatter)Obtains an instance of  ZonedDateTimefrom a text string using a specific formatter. | 
| static OffsetDateTime | OffsetDateTime. parse(CharSequence text,
     DateTimeFormatter formatter)Obtains an instance of  OffsetDateTimefrom a text string using a specific formatter. | 
| static LocalTime | LocalTime. parse(CharSequence text,
     DateTimeFormatter formatter)Obtains an instance of  LocalTimefrom a text string using a specific formatter. | 
| Modifier and Type | Method and Description | 
|---|---|
| TemporalAccessor | DateTimeFormatter. parse(CharSequence text)Fully parses the text producing a temporal object. | 
| TemporalAccessor | DateTimeFormatter. parse(CharSequence text,
     ParsePosition position)Parses the text using this formatter, providing control over the text position. | 
| <T> T | DateTimeFormatter. parse(CharSequence text,
     TemporalQuery<T> query)Fully parses the text producing an object of the specified type. | 
| TemporalAccessor | DateTimeFormatter. parseBest(CharSequence text,
         TemporalQuery<?>... queries)Fully parses the text producing an object of one of the specified types. | 
| TemporalAccessor | DateTimeFormatter. parseUnresolved(CharSequence text,
               ParsePosition position)Parses the text using this formatter, without resolving the result, intended
 for advanced use cases. | 
| Constructor and Description | 
|---|
| DateTimeParseException(String message,
                      CharSequence parsedData,
                      int errorIndex)Constructs a new exception with the specified message. | 
| DateTimeParseException(String message,
                      CharSequence parsedData,
                      int errorIndex,
                      Throwable cause)Constructs a new exception with the specified message and cause. | 
| Modifier and Type | Method and Description | 
|---|---|
| StringJoiner | StringJoiner. add(CharSequence newElement)Adds a copy of the given  CharSequencevalue as the next
 element of theStringJoinervalue. | 
| StringJoiner | StringJoiner. setEmptyValue(CharSequence emptyValue)Sets the sequence of characters to be used when determining the string
 representation of this  StringJoinerand no elements have been
 added yet, that is, when it is empty. | 
| Constructor and Description | 
|---|
| StringJoiner(CharSequence delimiter)Constructs a  StringJoinerwith no characters in it, with noprefixorsuffix, and a copy of the supplieddelimiter. | 
| StringJoiner(CharSequence delimiter,
            CharSequence prefix,
            CharSequence suffix)Constructs a  StringJoinerwith no characters in it using copies
 of the suppliedprefix,delimiterandsuffix. | 
| Modifier and Type | Method and Description | 
|---|---|
| Matcher | Pattern. matcher(CharSequence input)Creates a matcher that will match the given input against this pattern. | 
| static boolean | Pattern. matches(String regex,
       CharSequence input)Compiles the given regular expression and attempts to match the given
 input against it. | 
| Matcher | Matcher. reset(CharSequence input)Resets this matcher with a new input sequence. | 
| String[] | Pattern. split(CharSequence input)Splits the given input sequence around matches of this pattern. | 
| String[] | Pattern. split(CharSequence input,
     int limit)Splits the given input sequence around matches of this pattern. | 
| Stream<String> | Pattern. splitAsStream(CharSequence input)Creates a stream from the given input sequence around matches of this
 pattern. | 
| Modifier and Type | Method and Description | 
|---|---|
| static Collector<CharSequence,?,String> | Collectors. joining()Returns a  Collectorthat concatenates the input elements into aString, in encounter order. | 
| static Collector<CharSequence,?,String> | Collectors. joining(CharSequence delimiter)Returns a  Collectorthat concatenates the input elements,
 separated by the specified delimiter, in encounter order. | 
| static Collector<CharSequence,?,String> | Collectors. joining(CharSequence delimiter,
       CharSequence prefix,
       CharSequence suffix)Returns a  Collectorthat concatenates the input elements,
 separated by the specified delimiter, with the specified prefix and
 suffix, in encounter order. | 
| Modifier and Type | Method and Description | 
|---|---|
| static Collector<CharSequence,?,String> | Collectors. joining(CharSequence delimiter)Returns a  Collectorthat concatenates the input elements,
 separated by the specified delimiter, in encounter order. | 
| static Collector<CharSequence,?,String> | Collectors. joining(CharSequence delimiter,
       CharSequence prefix,
       CharSequence suffix)Returns a  Collectorthat concatenates the input elements,
 separated by the specified delimiter, with the specified prefix and
 suffix, in encounter order. | 
| Modifier and Type | Method and Description | 
|---|---|
| JavaFileObject | Filer. createClassFile(CharSequence name,
               Element... originatingElements)Creates a new class file, and returns an object to allow
 writing to it. | 
| FileObject | Filer. createResource(JavaFileManager.Location location,
              CharSequence pkg,
              CharSequence relativeName,
              Element... originatingElements)Creates a new auxiliary resource file for writing and returns a
 file object for it. | 
| JavaFileObject | Filer. createSourceFile(CharSequence name,
                Element... originatingElements)Creates a new source file and returns an object to allow
 writing to it. | 
| FileObject | Filer. getResource(JavaFileManager.Location location,
           CharSequence pkg,
           CharSequence relativeName)Returns an object for reading an existing resource. | 
| void | Messager. printMessage(Diagnostic.Kind kind,
            CharSequence msg)Prints a message of the specified kind. | 
| void | Messager. printMessage(Diagnostic.Kind kind,
            CharSequence msg,
            Element e)Prints a message of the specified kind at the location of the
 element. | 
| void | Messager. printMessage(Diagnostic.Kind kind,
            CharSequence msg,
            Element e,
            AnnotationMirror a)Prints a message of the specified kind at the location of the
 annotation mirror of the annotated element. | 
| void | Messager. printMessage(Diagnostic.Kind kind,
            CharSequence msg,
            Element e,
            AnnotationMirror a,
            AnnotationValue v)Prints a message of the specified kind at the location of the
 annotation value inside the annotation mirror of the annotated
 element. | 
| Modifier and Type | Method and Description | 
|---|---|
| static boolean | SourceVersion. isIdentifier(CharSequence name)Returns whether or not  nameis a syntactically valid
 identifier (simple name) or keyword in the latest source
 version. | 
| static boolean | SourceVersion. isKeyword(CharSequence s)Returns whether or not  sis a keyword or literal in the
  latest source version. | 
| static boolean | SourceVersion. isName(CharSequence name)Returns whether or not  nameis a syntactically valid
  qualified name in the latest source version. | 
| Modifier and Type | Interface and Description | 
|---|---|
| interface  | NameAn immutable sequence of characters. | 
| Modifier and Type | Method and Description | 
|---|---|
| boolean | Name. contentEquals(CharSequence cs)Compares this name to the specified  CharSequence. | 
| Modifier and Type | Method and Description | 
|---|---|
| Name | Elements. getName(CharSequence cs)Return a name with the same sequence of characters as the
 argument. | 
| PackageElement | Elements. getPackageElement(CharSequence name)Returns a package given its fully qualified name. | 
| TypeElement | Elements. getTypeElement(CharSequence name)Returns a type element given its canonical name. | 
| Modifier and Type | Class and Description | 
|---|---|
| class  | SegmentA segment of a character array representing a fragment
 of text. | 
| Modifier and Type | Method and Description | 
|---|---|
| CharSequence | Segment. subSequence(int start,
           int end)Returns a  CharSequencethat is a subsequence of this sequence. | 
| Modifier and Type | Method and Description | 
|---|---|
| CharSequence | SimpleJavaFileObject. getCharContent(boolean ignoreEncodingErrors)This implementation always throws UnsupportedOperationException. | 
| CharSequence | ForwardingFileObject. getCharContent(boolean ignoreEncodingErrors) | 
| CharSequence | FileObject. getCharContent(boolean ignoreEncodingErrors)Gets the character content of this file object, if available. | 
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