restconf/restconf-openapi/src/main/java/org/opendaylight/restconf/openapi/impl/SecuritySchemesStream.java

   1 /*
   2  * Copyright (c) 2023 PANTHEON.tech, s.r.o. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.restconf.openapi.impl;
   9
  10 import java.io.BufferedReader;
  11 import java.io.ByteArrayInputStream;
  12 import java.io.IOException;
  13 import java.io.InputStream;
  14 import java.io.InputStreamReader;
  15 import java.io.Reader;
  16 import java.nio.ByteBuffer;
  17 import java.nio.channels.Channels;
  18 import java.nio.channels.ReadableByteChannel;
  19 import java.nio.charset.StandardCharsets;
  20 import java.util.Map;
  21 import org.opendaylight.restconf.openapi.jaxrs.OpenApiBodyWriter;
  22 import org.opendaylight.restconf.openapi.model.OpenApiEntity;
  23 import org.opendaylight.restconf.openapi.model.SecuritySchemesEntity;
  24 import org.opendaylight.restconf.openapi.model.security.SecuritySchemeObject;
  25
  26 public final class SecuritySchemesStream extends InputStream {
  27     private final OpenApiBodyWriter writer;
  28     private final SecuritySchemesEntity securitySchemesEntity;
  29
  30     private Reader reader;
  31     private ReadableByteChannel channel;
  32
  33     public SecuritySchemesStream(final OpenApiBodyWriter writer,
  34             final Map<String, SecuritySchemeObject> securitySchemes) {
  35         this.writer = writer;
  36         this.securitySchemesEntity = new SecuritySchemesEntity(securitySchemes);
  37     }
  38
  39     @Override
  40     public int read() throws IOException {
  41         if (reader == null) {
  42             reader = new BufferedReader(
  43                 new InputStreamReader(new ByteArrayInputStream(writeNextEntity(securitySchemesEntity)),
  44                     StandardCharsets.UTF_8));
  45         }
  46         return reader.read();
  47     }
  48
  49     @Override
  50     public int read(final byte[] array, final int off, final int len) throws IOException {
  51         if (channel == null) {
  52             final var stream = new ByteArrayInputStream(writeNextEntity(securitySchemesEntity));
  53             channel = Channels.newChannel(stream);
  54         }
  55         return channel.read(ByteBuffer.wrap(array, off, len));
  56     }
  57
  58     private byte[] writeNextEntity(final OpenApiEntity next) throws IOException {
  59         writer.writeTo(next, null, null, null, null, null, null);
  60         return writer.readFrom();
  61     }
  62 }