1/* 2 * Copyright 2017 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package androidx.navigation.safe.args.generator 18 19import org.xmlpull.v1.XmlPullParser 20import org.xmlpull.v1.XmlPullParserFactory 21import java.io.Reader 22 23internal class XmlPositionParser(private val name: String, reader: Reader, val logger: NavLogger) { 24 private var startLine = 0 25 private var startColumn = 0 26 private val parser: XmlPullParser = XmlPullParserFactory.newInstance().newPullParser().apply { 27 setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, true) 28 setInput(reader) 29 } 30 31 fun name(): String = parser.name 32 33 fun traverseStartTags(onStartTag: () -> Boolean) { 34 while (parser.eventType != XmlPullParser.END_DOCUMENT) { 35 val processedLine = parser.lineNumber 36 val processedColumn = parser.columnNumber 37 if (parser.eventType == XmlPullParser.START_TAG) { 38 if (onStartTag()) { 39 return 40 } 41 } 42 43 if (processedLine == parser.lineNumber && processedColumn == parser.columnNumber) { 44 // otherwise onStart already called next() and we need to try to process current node 45 nextToken() 46 } 47 } 48 } 49 50 private fun nextToken() { 51 startLine = parser.lineNumber 52 startColumn = parser.columnNumber 53 parser.nextToken() 54 } 55 56 fun xmlPosition() = XmlPosition(name, startLine, startColumn - 1) 57 58 fun traverseInnerStartTags(onStartTag: () -> Unit) { 59 val innerDepth = parser.depth + 1 60 nextToken() 61 traverseStartTags { 62 if (innerDepth == parser.depth) { 63 onStartTag() 64 } 65 parser.depth < innerDepth 66 } 67 } 68 69 fun attrValue(namespace: String, name: String): String? = 70 (0 until parser.attributeCount).find { 71 parser.getAttributeNamespace(it) == namespace && name == parser.getAttributeName(it) 72 }?.let { parser.getAttributeValue(it) } 73 74 fun attrValueOrError(namespace: String, attrName: String): String? { 75 val value = attrValue(namespace, attrName) 76 if (value == null) { 77 logger.error(mandatoryAttrMissingError(name(), attrName), xmlPosition()) 78 } 79 return value 80 } 81} 82 83internal fun mandatoryAttrMissingError(tag: String, attr: String) = 84 "Mandatory attribute '$attr' for tag '$tag' is missing."