restconf/restconf-openapi/src/main/java/org/opendaylight/restconf/openapi/impl/SchemaStream.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.charset.StandardCharsets;
  17 import java.util.Deque;
  18 import org.opendaylight.restconf.openapi.jaxrs.OpenApiBodyWriter;
  19 import org.opendaylight.restconf.openapi.model.OpenApiEntity;
  20 import org.opendaylight.restconf.openapi.model.SchemaEntity;
  21
  22 public final class SchemaStream extends InputStream {
  23     private final Deque<SchemaEntity> stack;
  24     private final OpenApiBodyWriter writer;
  25
  26     private Reader reader;
  27
  28     public SchemaStream(final Deque<SchemaEntity> schemas, final OpenApiBodyWriter writer) {
  29         this.stack = schemas;
  30         this.writer = writer;
  31     }
  32
  33     @Override
  34     public int read() throws IOException {
  35         if (reader == null) {
  36             if (stack.isEmpty()) {
  37                 return -1;
  38             }
  39             reader = new BufferedReader(new InputStreamReader(new ByteArrayInputStream(writeNextEntity(stack.pop())),
  40                 StandardCharsets.UTF_8));
  41         }
  42
  43         var read = reader.read();
  44         while (read == -1) {
  45             if (stack.isEmpty()) {
  46                 return -1;
  47             }
  48             reader = new BufferedReader(new InputStreamReader(new ByteArrayInputStream(writeNextEntity(stack.pop())),
  49                 StandardCharsets.UTF_8));
  50             read = reader.read();
  51         }
  52
  53         return read;
  54     }
  55
  56     @Override
  57     public int read(final byte[] array, final int off, final int len) throws IOException {
  58         return super.read(array, off, len);
  59     }
  60
  61     private byte[] writeNextEntity(final OpenApiEntity entity) throws IOException {
  62         writer.writeTo(entity, null, null, null, null, null, null);
  63         return writer.readFrom();
  64     }
  65 }