Java : OutputStreamWriter con ejemplos

OutputStreamWriter (Java SE 21 & JDK 21) en Java con ejemplos.
Encontrará ejemplos de código en la mayoría de los métodos de OutputStreamWriter.

Nota :

Este artículo puede utilizar software de traducción para su comodidad. Consulte también la versión original en inglés.

Summary

Un OutputStreamWriter es un puente entre los flujos de caracteres y los flujos de bytes: los caracteres que se escriben en él se codifican en bytes utilizando un conjunto de caracteres especificado. El conjunto de caracteres que utiliza puede especificarse por nombre o puede proporcionarse explícitamente, o puede aceptarse el conjunto de caracteres predeterminado. (Traducción automática)

Class diagram

final var os = new ByteArrayOutputStream();

try (final var writer = new OutputStreamWriter(os)) {
    writer.write("abcd");
}

System.out.println(os); // abcd
System.out.println(Arrays.toString(os.toByteArray())); // [97, 98, 99, 100]

final var os = new ByteArrayOutputStream();

try (final var writer = new BufferedWriter(new OutputStreamWriter(os))) {
    writer.write("abcd");
    writer.newLine();
    writer.write("XYZ");
}

System.out.println(os);

// Result
// ↓
//abcd
//XYZ

Fields declared in Writer

lock

Consulte el siguiente enlace.

Writer con ejemplos

Constructors

OutputStreamWriter (OutputStream out)

Crea un OutputStreamWriter que utiliza la codificación de caracteres predeterminada, o donde out es un PrintStream, el conjunto de caracteres utilizado por el flujo de impresión. (Traducción automática)

final var os = new ByteArrayOutputStream();

try (final var writer = new OutputStreamWriter(os)) {
    writer.write("abcd");
}

System.out.println(os); // abcd
System.out.println(Arrays.toString(os.toByteArray())); // [97, 98, 99, 100]

OutputStreamWriter (OutputStream out, String charsetName)

Crea un OutputStreamWriter que utiliza el conjunto de caracteres nombrado. (Traducción automática)

final var sjis = "Shift_JIS";
final var os = new ByteArrayOutputStream();

try (final var writer = new OutputStreamWriter(os, sjis)) {
    writer.write("○△×");
}

System.out.println(os.toString(sjis)); // ○△×

final var bytes = os.toByteArray();
System.out.println(Arrays.toString(bytes)); // [-127, -101, -127, -94, -127, 126]

OutputStreamWriter (OutputStream out, Charset cs)

Crea un OutputStreamWriter que utiliza el conjunto de caracteres dado. (Traducción automática)

final var sjis = Charset.forName("Shift_JIS");
final var os = new ByteArrayOutputStream();

try (final var writer = new OutputStreamWriter(os, sjis)) {
    writer.write("○△×");
}

System.out.println(os.toString(sjis)); // ○△×

final var bytes = os.toByteArray();
System.out.println(Arrays.toString(bytes)); // [-127, -101, -127, -94, -127, 126]

OutputStreamWriter (OutputStream out, CharsetEncoder enc)

Crea un OutputStreamWriter que utiliza el codificador de caracteres indicado. (Traducción automática)

final var sjis = Charset.forName("Shift_JIS");
final var os = new ByteArrayOutputStream();

try (final var writer = new OutputStreamWriter(os, sjis.newEncoder())) {
    writer.write("○△×");
}

System.out.println(os.toString(sjis)); // ○△×

final var bytes = os.toByteArray();
System.out.println(Arrays.toString(bytes)); // [-127, -101, -127, -94, -127, 126]

Methods

void close ()

Cierra el flujo, lavándolo primero. (Traducción automática)

final var os = new ByteArrayOutputStream();

try (final var writer = new OutputStreamWriter(os)) {
    writer.write("abcd");
}

System.out.println(os); // abcd
System.out.println(Arrays.toString(os.toByteArray())); // [97, 98, 99, 100]

// An example without a try-with-resources statement.
final var os = new ByteArrayOutputStream();
final var writer = new OutputStreamWriter(os);
try {
    writer.write("abcd");
} finally {
    writer.close();
}

System.out.println(os); // abcd
System.out.println(Arrays.toString(os.toByteArray())); // [97, 98, 99, 100]

void flush ()

Limpia la corriente. (Traducción automática)

final var os = new ByteArrayOutputStream();

try (final var writer = new OutputStreamWriter(os)) {
    writer.write("abcd");

    final var ret1 = os.toString();
    System.out.println(ret1.isEmpty()); // true

    writer.flush();

    final var ret2 = os.toString();
    System.out.println(ret2); // abcd

    writer.write("XYZ");

    final var ret3 = os.toString();
    System.out.println(ret3); // abcd
}

final var ret4 = os.toString();
System.out.println(ret4); // abcdXYZ

String getEncoding ()

Devuelve el nombre de la codificación de caracteres que utiliza esta secuencia. (Traducción automática)

try (final var writer = new OutputStreamWriter(new ByteArrayOutputStream())) {
    final var ret = writer.getEncoding();
    System.out.println(ret); // UTF8
}

final var sjis = Charset.forName("Shift_JIS");

try (final var writer = new OutputStreamWriter(new ByteArrayOutputStream(), sjis)) {
    final var ret = writer.getEncoding();
    System.out.println(ret); // SJIS
}

void write (char[] cbuf, int off, int len)

Escribe una parte de una matriz de caracteres. (Traducción automática)

final char[] cbuf = {'a', 'b', 'c', 'd'};

{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(cbuf, 0, 1);
    }
    System.out.println(os); // a
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(cbuf, 0, 2);
    }
    System.out.println(os); // ab
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(cbuf, 0, 3);
    }
    System.out.println(os); // abc
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(cbuf, 0, 4);
    }
    System.out.println(os); // abcd
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        //writer.write(cbuf, 0, 5); // IndexOutOfBoundsException
    }
}

final char[] cbuf = {'a', 'b', 'c', 'd'};

{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(cbuf, 0, 4);
    }
    System.out.println(os); // abcd
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(cbuf, 1, 3);
    }
    System.out.println(os); // bcd
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(cbuf, 2, 2);
    }
    System.out.println(os); // cd
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(cbuf, 3, 1);
    }
    System.out.println(os); // d
}

void write (int c)

Escribe un solo caracter. (Traducción automática)

final var os = new ByteArrayOutputStream();

try (final var writer = new OutputStreamWriter(os)) {
    writer.write('a');
    writer.write('b');
    writer.write('c');
}

System.out.println(os); // abc

void write (String str, int off, int len)

Escribe una parte de una cadena. (Traducción automática)

final var str = "abcd";

{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(str, 0, 1);
    }
    System.out.println(os); // a
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(str, 0, 2);
    }
    System.out.println(os); // ab
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(str, 0, 3);
    }
    System.out.println(os); // abc
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(str, 0, 4);
    }
    System.out.println(os); // abcd
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        //writer.write(str, 0, 5); // IndexOutOfBoundsException
    }
}

final var str = "abcd";

{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(str, 0, 4);
    }
    System.out.println(os); // abcd
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(str, 1, 3);
    }
    System.out.println(os); // bcd
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(str, 2, 2);
    }
    System.out.println(os); // cd
}
{
    final var os = new ByteArrayOutputStream();
    try (final var writer = new OutputStreamWriter(os)) {
        writer.write(str, 3, 1);
    }
    System.out.println(os); // d
}

Methods declared in Writer

append, append, append, nullWriter, write, write

Consulte el siguiente enlace.

Writer con ejemplos

Ejemplos de API

Java : OutputStreamWriter con ejemplos

Summary

Fields declared in Writer

lock

Constructors

OutputStreamWriter (OutputStream out)

OutputStreamWriter (OutputStream out, String charsetName)

OutputStreamWriter (OutputStream out, Charset cs)

OutputStreamWriter (OutputStream out, CharsetEncoder enc)

Methods

void close ()

void flush ()

String getEncoding ()

void write (char[] cbuf, int off, int len)

void write (int c)

void write (String str, int off, int len)

Methods declared in Writer

append, append, append, nullWriter, write, write

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