org.apache.juneau.serializer.SerializerPipe Maven / Gradle / Ivy
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// * *
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package org.apache.juneau.serializer;
import static org.apache.juneau.common.internal.IOUtils.*;
import static org.apache.juneau.common.internal.ThrowableUtils.*;
import static org.apache.juneau.internal.ClassUtils.*;
import java.io.*;
import java.nio.charset.*;
import org.apache.juneau.*;
import org.apache.juneau.common.internal.*;
import org.apache.juneau.internal.*;
/**
* A wrapper around an object that a serializer sends its output to.
*
*
* For character-based serializers, the output object can be any of the following:
*
* - {@link Writer}
*
- {@link OutputStream} - Output will be written as UTF-8 encoded stream.
*
- {@link File} - Output will be written as system-default encoded stream.
*
- {@link StringBuilder}
*
*
*
* For stream-based serializers, the output object can be any of the following:
*
* - {@link OutputStream}
*
- {@link File}
*
*
* See Also:
*/
public final class SerializerPipe implements Closeable {
private final Object output;
private final boolean autoClose;
private OutputStream outputStream;
private Writer writer;
private Charset charset;
/**
* Writer-based constructor.
*
* @param output The object to pipe the serializer output to.
*/
SerializerPipe(Object output, Charset streamCharset, Charset fileCharset) {
boolean isFile = (output instanceof File);
this.output = output;
this.autoClose = isFile;
Charset cs = isFile ? fileCharset : streamCharset;
if (cs == null)
cs = isFile ? Charset.defaultCharset() : UTF8;
this.charset = cs;
}
/**
* Stream-based constructor.
*
* @param output The object to pipe the serializer output to.
*/
SerializerPipe(Object output) {
this.output = output;
this.autoClose = false;
this.charset = null;
}
/**
* Wraps the specified output object inside an output stream.
*
*
* Subclasses can override this method to implement their own specialized output streams.
*
*
* This method can be used if the output object is any of the following class types:
*
* - {@link OutputStream}
*
- {@link File}
*
*
* @return
* The output object wrapped in an output stream.
* Calling {@link OutputStream#close()} on the returned object simply flushes the response and does not close
* the underlying stream.
* @throws IOException If object could not be converted to an output stream.
*/
public OutputStream getOutputStream() throws IOException {
if (output == null)
throw new IOException("Output cannot be null.");
if (output instanceof OutputStream)
outputStream = (OutputStream)output;
else if (output instanceof File)
outputStream = new BufferedOutputStream(new FileOutputStream((File)output));
else
throw new IOException("Cannot convert object of type "+className(output)+" to an OutputStream.");
return new NoCloseOutputStream(outputStream);
}
/**
* Wraps the specified output object inside a writer.
*
*
* Subclasses can override this method to implement their own specialized writers.
*
*
* This method can be used if the output object is any of the following class types:
*
* - {@link Writer}
*
- {@link OutputStream} - Output will be written as UTF-8 encoded stream.
*
- {@link File} - Output will be written as system-default encoded stream.
*
*
* @return
* The output object wrapped in a writer.
* Calling {@link Writer#close()} on the returned object simply flushes the response and does not close
* the underlying writer.
* @throws SerializeException If object could not be converted to a writer.
*/
public Writer getWriter() throws SerializeException {
if (output == null)
throw new SerializeException("Output cannot be null.");
try {
if (output instanceof Writer)
writer = (Writer)output;
else if (output instanceof OutputStream)
writer = new OutputStreamWriter((OutputStream)output, charset);
else if (output instanceof File)
writer = new OutputStreamWriter(new BufferedOutputStream(new FileOutputStream((File)output)));
else if (output instanceof StringBuilder)
writer = new StringBuilderWriter((StringBuilder)output);
else
throw new SerializeException("Cannot convert object of type "+className(output)+" to a Writer.");
} catch (FileNotFoundException e) {
throw cast(SerializeException.class, e);
}
return new NoCloseWriter(writer);
}
/**
* Overwrites the writer in this pipe.
*
*
* Used when wrapping the writer returned by {@link #getWriter()} so that the wrapped writer will be flushed
* and closed when {@link #close()} is called.
*
* @param writer The wrapped writer.
*/
public void setWriter(Writer writer) {
this.writer = writer;
}
/**
* Overwrites the output stream in this pipe.
*
*
* Used when wrapping the stream returned by {@link #getOutputStream()} so that the wrapped stream will be flushed
* when {@link #close()} is called.
*
* @param outputStream The wrapped stream.
*/
public void setOutputStream(OutputStream outputStream) {
this.outputStream = outputStream;
}
/**
* Returns the raw output object passed into this session.
*
* @return The raw output object passed into this session.
*/
public Object getRawOutput() {
return output;
}
/**
* Closes the output pipe.
*/
@Override /* Closeable */
public void close() {
try {
IOUtils.flush(writer, outputStream);
if (autoClose)
IOUtils.close(writer, outputStream);
} catch (IOException e) {
throw new BeanRuntimeException(e);
}
}
}