yang/yang-parser-impl/src/main/java/org/opendaylight/yangtools/yang/parser/stmt/rfc6020/YinStatementSourceImpl.java

   1 /*
   2  * Copyright (c) 2015 Cisco Systems, Inc. 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
   9 package org.opendaylight.yangtools.yang.parser.stmt.rfc6020;
  10
  11 import com.google.common.base.Preconditions;
  12 import com.google.common.io.ByteStreams;
  13 import java.io.BufferedInputStream;
  14 import java.io.ByteArrayInputStream;
  15 import java.io.File;
  16 import java.io.IOException;
  17 import java.io.InputStream;
  18 import java.net.URISyntaxException;
  19 import javax.xml.stream.XMLInputFactory;
  20 import javax.xml.stream.XMLStreamException;
  21 import javax.xml.stream.XMLStreamReader;
  22 import org.opendaylight.yangtools.yang.parser.impl.YinStatementParserImpl;
  23 import org.opendaylight.yangtools.yang.parser.spi.source.PrefixToModule;
  24 import org.opendaylight.yangtools.yang.parser.spi.source.QNameToStatementDefinition;
  25 import org.opendaylight.yangtools.yang.parser.spi.source.StatementStreamSource;
  26 import org.opendaylight.yangtools.yang.parser.spi.source.StatementWriter;
  27 import org.opendaylight.yangtools.yang.parser.util.NamedFileInputStream;
  28 import org.slf4j.Logger;
  29 import org.slf4j.LoggerFactory;
  30
  31 /**
  32  *
  33  * This class represents implementation of StatementStreamSource
  34  * in order to emit YIN statements using supplied StatementWriter
  35  *
  36  */
  37 public class YinStatementSourceImpl implements StatementStreamSource {
  38
  39     private static final Logger LOG = LoggerFactory.getLogger(YinStatementSourceImpl.class);
  40     private static XMLInputFactory xmlInputFactory = XMLInputFactory.newFactory();
  41
  42     private YinStatementParserImpl yinStatementModelParser;
  43     private XMLStreamReader streamReader;
  44     private InputStream inputStream;
  45     private String fileName;
  46     private boolean isAbsolute;
  47
  48     public YinStatementSourceImpl(final InputStream inputStream) {
  49         yinStatementModelParser = new YinStatementParserImpl(inputStream.toString());
  50         this.inputStream = new BufferedInputStream(inputStream);
  51         this.inputStream.mark(Integer.MAX_VALUE);
  52     }
  53
  54     public YinStatementSourceImpl(final String fileName, final boolean isAbsolute) {
  55         yinStatementModelParser = new YinStatementParserImpl(fileName);
  56         this.fileName = Preconditions.checkNotNull(fileName);
  57         this.isAbsolute = isAbsolute;
  58     }
  59
  60     @Override
  61     public void writePreLinkage(StatementWriter writer, QNameToStatementDefinition stmtDef) {
  62         initializeReader();
  63         yinStatementModelParser.setAttributes(writer, stmtDef);
  64         yinStatementModelParser.walk(streamReader);
  65     }
  66
  67     @Override
  68     public void writeLinkage(StatementWriter writer, QNameToStatementDefinition stmtDef, final PrefixToModule preLinkagePrefixes) {
  69         initializeReader();
  70         yinStatementModelParser.setAttributes(writer, stmtDef, preLinkagePrefixes);
  71         yinStatementModelParser.walk(streamReader);
  72     }
  73
  74     @Override
  75     public void writeLinkageAndStatementDefinitions(StatementWriter writer, QNameToStatementDefinition stmtDef,
  76             PrefixToModule prefixes) {
  77         initializeReader();
  78         yinStatementModelParser.setAttributes(writer, stmtDef, prefixes);
  79         yinStatementModelParser.walk(streamReader);
  80     }
  81
  82     @Override
  83     public void writeFull(StatementWriter writer, QNameToStatementDefinition stmtDef, PrefixToModule prefixes) {
  84         initializeReader();
  85         yinStatementModelParser.setAttributes(writer, stmtDef, prefixes);
  86         yinStatementModelParser.walk(streamReader);
  87         closeReader();
  88     }
  89
  90     private void initializeReader() {
  91         try {
  92             if (fileName != null) {
  93                 inputStream = loadFile(fileName, isAbsolute);
  94                 streamReader = xmlInputFactory.createXMLStreamReader(inputStream);
  95             } else {
  96                 inputStream.reset();
  97                 streamReader = xmlInputFactory.createXMLStreamReader(new ByteArrayInputStream(ByteStreams.toByteArray
  98                         (inputStream)));
  99             }
 100         } catch (XMLStreamException e) {
 101             LOG.warn("Error while creating XMLStreamReader from input stream", e);
 102         } catch (URISyntaxException e) {
 103             LOG.warn("File name {} cannot be parsed as URI reference", fileName, e);
 104         } catch (IOException e) {
 105             LOG.warn("File {} cannot be found or read into string ", fileName, e);
 106         }
 107     }
 108
 109     private void closeReader() {
 110         try {
 111             inputStream.close();
 112             streamReader.close();
 113         } catch (XMLStreamException e) {
 114             LOG.warn("Error occured while freeing associated resources", e);
 115         } catch (IOException e) {
 116             LOG.warn("I/O error occured during closing the input stream", e);
 117         }
 118     }
 119
 120     private InputStream loadFile(final String fileName, boolean isAbsolute) throws URISyntaxException, IOException {
 121         final File file;
 122         if (isAbsolute) {
 123             file = new File(fileName);
 124         } else {
 125             file = new File(getClass().getResource(fileName).toURI());
 126         }
 127
 128         return new NamedFileInputStream(file, fileName);
 129     }
 130 }