ReaderProvider.java

/*
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 *
 * Copyright (c) 2010-2014 Oracle and/or its affiliates. All rights reserved.
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 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * http://glassfish.java.net/public/CDDL+GPL_1_1.html
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 * file and include the License file at packager/legal/LICENSE.txt.
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 * GPL Classpath Exception:
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package org.glassfish.jersey.message.internal;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;

import javax.ws.rs.Consumes;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;

import javax.inject.Singleton;

import org.glassfish.jersey.message.MessageUtils;

/**
 *
 * @author Paul Sandoz
 */
@Produces({"text/plain", "*/*"})
@Consumes({"text/plain", "*/*"})
@Singleton
public final class ReaderProvider extends AbstractMessageReaderWriterProvider<Reader> {

    @Override
    public boolean isReadable(final Class<?> type, final Type genericType, final Annotation[] annotations,
                              final MediaType mediaType) {
        return Reader.class == type;
    }

    @Override
    public Reader readFrom(
            final Class<Reader> type,
            final Type genericType,
            final Annotation[] annotations,
            final MediaType mediaType,
            final MultivaluedMap<String, String> httpHeaders,
            final InputStream inputStream) throws IOException {

        final EntityInputStream entityStream = EntityInputStream.create(inputStream);
        if (entityStream.isEmpty()) {
            return new BufferedReader(new InputStreamReader(
                    new ByteArrayInputStream(new byte[0]), MessageUtils.getCharset(mediaType)));
        }

        return new BufferedReader(new InputStreamReader(entityStream, getCharset(mediaType)));
    }

    @Override
    public boolean isWriteable(final Class<?> type, final Type genericType, final Annotation[] annotations,
                               final MediaType mediaType) {
        return Reader.class.isAssignableFrom(type);
    }

    @Override
    public void writeTo(
            final Reader t,
            final Class<?> type,
            final Type genericType,
            final Annotation[] annotations,
            final MediaType mediaType,
            final MultivaluedMap<String, Object> httpHeaders,
            final OutputStream entityStream) throws IOException {
        try {
            final OutputStreamWriter out = new OutputStreamWriter(entityStream,
                    getCharset(mediaType));
            writeTo(t, out);
            out.flush();
        } finally {
            t.close();
        }

    }
}