--- /dev/null
+/**
+ * ============LICENSE_START====================================================
+ * org.onap.ccsdk
+ * ===========================================================================
+ * Copyright (c) 2023 AT&T Intellectual Property. All rights reserved.
+ * ===========================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END====================================================
+ *
+ */
+
+package org.onap.ccsdk.apps.cadi.wsse;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Stack;
+
+import javax.xml.stream.XMLStreamException;
+
+/**
+ * XReader
+ * This class works similarly as StAX, except StAX has more behavior than is needed. That would be ok, but
+ * StAX also was Buffering in their code in such as way as to read most if not all the incoming stream into memory,
+ * defeating the purpose of pre-reading only the Header
+ *
+ * This Reader does no back-tracking, but is able to create events based on syntax and given state only, leaving the
+ * Read-ahead mode of the InputStream up to the other classes.
+ *
+ * At this time, we only implement the important events, though if this is good enough, it could be expanded, perhaps to
+ * replace the original XMLReader from StAX.
+ *
+ * @author Jonathan
+ *
+ */
+// @SuppressWarnings("restriction")
+public class XReader {
+ private XEvent curr,another;
+ private InputStream is;
+ private ByteArrayOutputStream baos;
+ private int state, count, last;
+
+ private Stack<Map<String,String>> nsses;
+
+ public XReader(InputStream is) {
+ this.is = is;
+ curr = another = null;
+ baos = new ByteArrayOutputStream();
+ state = BEGIN_DOC;
+ count = 0;
+ nsses = new Stack<Map<String,String>>();
+ }
+
+ public boolean hasNext() throws XMLStreamException {
+ if (curr==null) {
+ curr = parse();
+ }
+ return curr!=null;
+ }
+
+ public XEvent nextEvent() {
+ XEvent xe = curr;
+ curr = null;
+ return xe;
+ }
+
+ //
+ // State Flags
+ //
+ // Note: The State of parsing XML can be complicated. There are too many to cleanly keep in "booleans". Additionally,
+ // there are certain checks that can be better made with Bitwise operations within switches
+ // Keeping track of state this way also helps us to accomplish logic without storing any back characters except one
+ private final static int BEGIN_DOC= 0x000001;
+ private final static int DOC_TYPE= 0x000002;
+ private final static int QUESTION_F= 0x000004;
+ private final static int QUESTION = 0x000008;
+ private final static int START_TAG = 0x000010;
+ private final static int END_TAG = 0x000020;
+ private final static int VALUE= 0x000040;
+ private final static int COMMENT = 0x001000;
+ private final static int COMMENT_E = 0x002000;
+ private final static int COMMENT_D1 =0x010000;
+ private final static int COMMENT_D2 =0x020000;
+ private final static int COMMENT_D3 =0x040000;
+ private final static int COMMENT_D4 =0x080000;
+ // useful combined Comment states
+ private final static int IN_COMMENT=COMMENT|COMMENT_E|COMMENT_D1|COMMENT_D2;
+ private final static int COMPLETE_COMMENT = COMMENT|COMMENT_E|COMMENT_D1|COMMENT_D2|COMMENT_D3|COMMENT_D4;
+
+
+ private XEvent parse() throws XMLStreamException {
+ Map<String,String> nss = nsses.isEmpty()?null:nsses.peek();
+
+ XEvent rv;
+ if ((rv=another)!=null) { // "another" is a tag that may have needed to be created, but not
+ // immediately returned. Save for next parse. If necessary, this could be turned into
+ // a FIFO storage, but a single reference is enough for now.
+ another = null; // "rv" is now set for the Event, and will be returned. Set to Null.
+ } else {
+ boolean go = true;
+ int c=0;
+
+ try {
+ while (go && (c=is.read())>=0) {
+ ++count;
+ switch(c) {
+ case '<': // Tag is opening
+ state|=~BEGIN_DOC; // remove BEGIN_DOC flag, this is possibly an XML Doc
+ XEvent cxe = null;
+ if (baos.size()>0) { // If there are any characters between tags, we send as Character Event
+ String chars = baos.toString().trim(); // Trim out WhiteSpace before and after
+ if (chars.length()>0) { // don't send if Characters were only whitespace
+ cxe = new XEvent.Characters(chars);
+ baos.reset();
+ go = false;
+ }
+ }
+ last = c; // make sure "last" character is set for use in "ParseTag"
+ Tag t = parseTag(); // call subroutine to process the tag as a unit
+ String ns;
+ switch(t.state&(START_TAG|END_TAG)) {
+ case START_TAG:
+ nss = getNss(nss,t); // Only Start Tags might have NS Attributes
+ // Get any NameSpace elements from tag. If there are, nss will become
+ // a new Map with all the previous NSs plus the new. This provides
+ // scoping behavior when used with the Stack
+ // drop through on purpose
+ case END_TAG:
+ ns = t.prefix==null||nss==null?"":nss.get(t.prefix); // Get the namespace from prefix (if exists)
+ break;
+ default:
+ ns = "";
+ }
+ if (ns==null)
+ throw new XMLStreamException("Invalid Namespace Prefix at " + count);
+ go = false;
+ switch(t.state) { // based on
+ case DOC_TYPE:
+ rv = new XEvent.StartDocument();
+ break;
+ case COMMENT:
+ rv = new XEvent.Comment(t.value);
+ break;
+ case START_TAG:
+ rv = new XEvent.StartElement(ns,t.name);
+ nsses.push(nss); // Change potential scope for Namespace
+ break;
+ case END_TAG:
+ rv = new XEvent.EndElement(ns,t.name);
+ nss = nsses.pop(); // End potential scope for Namespace
+ break;
+ case START_TAG|END_TAG: // This tag is both start/end aka <myTag/>
+ rv = new XEvent.StartElement(ns,t.name);
+ if (last=='/')another = new XEvent.EndElement(ns,t.name);
+ }
+ if (cxe!=null) { // if there is a Character Event, it actually should go first. ow.
+ another = rv; // Make current Event the "another" or next event, and
+ rv = cxe; // send Character Event now
+ }
+ break;
+ case ' ':
+ case '\t':
+ case '\n':
+ if ((state&BEGIN_DOC)==BEGIN_DOC) { // if Whitespace before doc, just ignore
+ break;
+ }
+ // fallthrough on purpose
+ default:
+ if ((state&BEGIN_DOC)==BEGIN_DOC) { // if there is any data at the start other than XML Tag, it's not XML
+ throw new XMLStreamException("Parse Error: This is not an XML Doc");
+ }
+ baos.write(c); // save off Characters
+ }
+ last = c; // Some processing needs to know what the last character was, aka Escaped characters... ex \"
+ }
+ } catch (IOException e) {
+ throw new XMLStreamException(e); // all errors parsing will be treated as XMLStreamErrors (like StAX)
+ }
+ if (c==-1 && (state&BEGIN_DOC)==BEGIN_DOC) { // Normally, end of stream is ok, however, we need to know if the
+ throw new XMLStreamException("Premature End of File"); // document isn't an XML document, so we throw exception if it
+ } // hasn't yet been determined to be an XML Doc
+ }
+ return rv;
+ }
+
+ /**
+ * parseTag
+ *
+ * Parsing a Tag is somewhat complicated, so it's helpful to separate this process from the
+ * higher level Parsing effort
+ * @return
+ * @throws IOException
+ * @throws XMLStreamException
+ */
+ private Tag parseTag() throws IOException, XMLStreamException {
+ Tag tag = null;
+ boolean go = true;
+ state = 0;
+ int c, quote=0; // If "quote" is 0, then we're not in a quote. We set ' (in pretag) or " in attribs accordingly to denote quoted
+ String prefix=null,name=null,value=null;
+ baos.reset();
+
+ while (go && (c=is.read())>=0) {
+ ++count;
+ if (quote!=0) { // If we're in a quote, we only end if we hit another quote of the same time, not preceded by \
+ if (c==quote && last!='\\') {
+ quote=0;
+ } else {
+ baos.write(c);
+ }
+ } else if ((state&COMMENT)==COMMENT) { // similar to Quote is being in a comment
+ switch(c) {
+ case '-':
+ switch(state) { // XML has a complicated Quote set... <!-- --> ... we keep track if each has been met with flags.
+ case COMMENT|COMMENT_E:
+ state|=COMMENT_D1;
+ break;
+ case COMMENT|COMMENT_E|COMMENT_D1:
+ state|=COMMENT_D2;
+ baos.reset(); // clear out "!--", it's a Comment
+ break;
+ case COMMENT|COMMENT_E|COMMENT_D1|COMMENT_D2:
+ state|=COMMENT_D3;
+ baos.write(c);
+ break;
+ case COMMENT|COMMENT_E|COMMENT_D1|COMMENT_D2|COMMENT_D3:
+ state|=COMMENT_D4;
+ baos.write(c);
+ break;
+ }
+ break;
+ case '>': // Tag indicator has been found, do we have all the comment characters in line?
+ if ((state&COMPLETE_COMMENT)==COMPLETE_COMMENT) {
+ byte ba[] = baos.toByteArray();
+ tag = new Tag(null,null, new String(ba,0,ba.length-2));
+ baos.reset();
+ go = false;
+ break;
+ }
+ // fall through on purpose
+ default:
+ state&=~(COMMENT_D3|COMMENT_D4);
+ if ((state&IN_COMMENT)!=IN_COMMENT) state&=~IN_COMMENT; // false alarm, it's not actually a comment
+ baos.write(c);
+ }
+ } else { // Normal Tag Processing loop
+ switch(c) {
+ case '?':
+ switch(state & (QUESTION_F|QUESTION)) { // Validate the state of Doc tag... <?xml ... ?>
+ case QUESTION_F:
+ state |= DOC_TYPE;
+ state &= ~QUESTION_F;
+ break;
+ case 0:
+ state |=QUESTION_F;
+ break;
+ default:
+ throw new IOException("Bad character [?] at " + count);
+ }
+ break;
+ case '!':
+ if (last=='<') {
+ state|=COMMENT|COMMENT_E; // likely a comment, continue processing in Comment Loop
+ }
+ baos.write(c);
+ break;
+ case '/':
+ state|=(last=='<'?END_TAG:(END_TAG|START_TAG)); // end tag indicator </xxx>, ,or both <xxx/>
+ break;
+ case ':':
+ prefix=baos.toString(); // prefix indicator
+ baos.reset();
+ break;
+ case '=': // used in Attributes
+ name=baos.toString();
+ baos.reset();
+ state|=VALUE;
+ break;
+ case '>': // end the tag, which causes end of this subprocess as well as formulation of the found data
+ go = false;
+ // passthrough on purpose
+ case ' ':
+ case '\t':
+ case '\n': // white space indicates change in internal tag state, ex between name and between attributes
+ if ((state&VALUE)==VALUE) {
+ value = baos.toString(); // we're in VALUE state, add characters to Value
+ } else if (name==null) {
+ name = baos.toString(); // we're in Name state (default) add characters to Name
+ }
+ baos.reset(); // we've assigned chars, reset buffer
+ if (name!=null) { // Name is not null, there's a tag in the offing here...
+ Tag t = new Tag(prefix,name,value);
+ if (tag==null) { // Set as the tag to return, if not exists
+ tag = t;
+ } else { // if we already have a Tag, then we'll treat this one as an attribute
+ tag.add(t);
+ }
+ }
+ prefix=name=value=null; // reset these values in case we loop for attributes.
+ break;
+ case '\'': // is the character one of two kinds of quote?
+ case '"':
+ if (last!='\\') {
+ quote=c;
+ break;
+ }
+ // Fallthrough ok
+ default:
+ baos.write(c); // write any unprocessed bytes into buffer
+
+ }
+ }
+ last = c;
+ }
+ int type = state&(DOC_TYPE|COMMENT|END_TAG|START_TAG); // get just the Tag states and turn into Type for Tag
+ if (type==0) {
+ type=START_TAG;
+ }
+ if (tag!=null) {
+ tag.state|=type; // add the appropriate Tag States
+ }
+ return tag;
+ }
+
+ /**
+ * getNSS
+ *
+ * If the tag contains some Namespace attributes, create a new nss from the passed in one, copy all into it, then add
+ * This provides Scoping behavior
+ *
+ * if Nss is null in the first place, create an new nss, so we don't have to deal with null Maps.
+ *
+ * @param nss
+ * @param t
+ * @return
+ */
+ private Map<String, String> getNss(Map<String, String> nss, Tag t) {
+ Map<String,String> newnss = null;
+ if (t.attribs!=null) {
+ for (Tag tag : t.attribs) {
+ if ("xmlns".equals(tag.prefix)) {
+ if (newnss==null) {
+ newnss = new HashMap<>();
+ if (nss!=null)newnss.putAll(nss);
+ }
+ newnss.put(tag.name, tag.value);
+ }
+ }
+ }
+ //return newnss==null?(nss==null?new HashMap<String,String>():nss):newnss;
+ if (newnss==null) {
+ if (nss==null) {
+ newnss = new HashMap<>();
+ } else {
+ newnss = nss;
+ }
+ }
+ return newnss;
+ }
+
+ /**
+ * The result of the parseTag method
+ *
+ * Data is split up into prefix, name and value portions. "Tags" with Values that are inside a Tag are known in XLM
+ * as Attributes.
+ *
+ * @author Jonathan
+ *
+ */
+ public class Tag {
+ public int state;
+ public String prefix,name,value;
+ public List<Tag> attribs;
+
+ public Tag(String prefix, String name, String value) {
+ this.prefix = prefix;
+ this.name = name;
+ this.value = value;
+ attribs = null;
+ }
+
+ /**
+ * add an attribute
+ * Not all tags need attributes... lazy instantiate to save time and memory
+ * @param tag
+ */
+ public void add(Tag attrib) {
+ if (attribs == null) {
+ attribs = new ArrayList<>();
+ }
+ attribs.add(attrib);
+ }
+
+ public String toString() {
+ StringBuffer sb = new StringBuffer();
+ if (prefix!=null) {
+ sb.append(prefix);
+ sb.append(':');
+ }
+ sb.append(name==null?"!!ERROR!!":name);
+
+ char quote = ((state&DOC_TYPE)==DOC_TYPE)?'\'':'"';
+ if (value!=null) {
+ sb.append('=');
+ sb.append(quote);
+ sb.append(value);
+ sb.append(quote);
+ }
+ return sb.toString();
+ }
+ }
+
+}
Code Review / ccsdk / apps.git / blobdiff