Java tutorial
/* * Copyright (c) 2002-2016 Gargoyle Software Inc. * * 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. */ package com.gargoylesoftware.htmlunit.html; import static com.gargoylesoftware.htmlunit.BrowserVersionFeatures.HTMLTEXTAREA_REMOVE_NEWLINE_FROM_TEXT; import java.util.Iterator; import java.util.List; import java.util.regex.Pattern; import org.apache.commons.lang3.StringUtils; import com.gargoylesoftware.htmlunit.BrowserVersion; /** * Utility to handle conversion from HTML code to string. * TODO: simplify it (it is just copied from what was available in DomNode and subclasses). * @author Marc Guillemot * @author Ahmed Ashour * @author Ronald Brill */ class HtmlSerializer { private final StringBuilder buffer_ = new StringBuilder(); /** Indicates a block. Will be rendered as line separator (multiple block marks are ignored) */ protected static final String AS_TEXT_BLOCK_SEPARATOR = "bs"; private static final int AS_TEXT_BLOCK_SEPARATOR_LENGTH = AS_TEXT_BLOCK_SEPARATOR.length(); /** Indicates a new line. Will be rendered as line separator. */ protected static final String AS_TEXT_NEW_LINE = "nl"; private static final int AS_TEXT_NEW_LINE_LENGTH = AS_TEXT_NEW_LINE.length(); /** Indicates a non blank that can't be trimmed or reduced. */ protected static final String AS_TEXT_BLANK = "blank"; /** Indicates a tab. */ protected static final String AS_TEXT_TAB = "tab"; private static final Pattern TEXT_AREA_PATTERN = Pattern.compile("\r?\n"); private boolean appletEnabled_; private boolean ignoreMaskedElements_ = true; /** * Converts an HTML node to text. * @param node a node * @return the text representation according to the setting of this serializer */ public String asText(final DomNode node) { appletEnabled_ = node.getPage().getWebClient().getOptions().isAppletEnabled(); buffer_.setLength(0); appendNode(node); final String response = buffer_.toString(); buffer_.setLength(0); return cleanUp(response); } protected String cleanUp(String text) { // ignore <br/> at the end of a block text = reduceWhitespace(text); text = StringUtils.replace(text, AS_TEXT_BLANK, " "); final String ls = System.getProperty("line.separator"); text = StringUtils.replace(text, AS_TEXT_NEW_LINE, ls); // text = CLEAN_UP_PATTERN.matcher(text).replaceAll(ls); // many block sep => 1 new line text = StringUtils.replace(text, AS_TEXT_BLOCK_SEPARATOR, ls); text = StringUtils.replace(text, AS_TEXT_TAB, "\t"); return text; } private String reduceWhitespace(String text) { text = text.trim(); // remove white spaces before or after block separators text = reduceWhiteSpaceAroundBlockSeparator(text); // remove leading block separators while (text.startsWith(AS_TEXT_BLOCK_SEPARATOR)) { text = text.substring(AS_TEXT_BLOCK_SEPARATOR_LENGTH); } // remove trailing block separators while (text.endsWith(AS_TEXT_BLOCK_SEPARATOR)) { text = text.substring(0, text.length() - AS_TEXT_BLOCK_SEPARATOR_LENGTH); } text = text.trim(); final StringBuilder buffer = new StringBuilder(text.length()); boolean whitespace = false; for (final char ch : text.toCharArray()) { // Translate non-breaking space to regular space. if (ch == (char) 160) { buffer.append(' '); whitespace = false; } else { if (whitespace) { if (!Character.isWhitespace(ch)) { buffer.append(ch); whitespace = false; } } else { if (Character.isWhitespace(ch)) { whitespace = true; buffer.append(' '); } else { buffer.append(ch); } } } } return buffer.toString(); } private static String reduceWhiteSpaceAroundBlockSeparator(final String text) { int p0 = text.indexOf(AS_TEXT_BLOCK_SEPARATOR); if (p0 == -1) { return text; } final int length = text.length(); if (length <= AS_TEXT_BLOCK_SEPARATOR_LENGTH) { return text; } final StringBuilder result = new StringBuilder(length); int start = 0; while (p0 != -1) { int p1 = p0 + AS_TEXT_BLOCK_SEPARATOR_LENGTH; while (p0 != start && Character.isWhitespace(text.charAt(p0 - 1))) { p0--; } if (p0 >= AS_TEXT_NEW_LINE_LENGTH && text.startsWith(AS_TEXT_NEW_LINE, p0 - AS_TEXT_NEW_LINE_LENGTH)) { p0 = p0 - AS_TEXT_NEW_LINE_LENGTH; } result.append(text.substring(start, p0)).append(AS_TEXT_BLOCK_SEPARATOR); while (p1 < length && Character.isWhitespace(text.charAt(p1))) { p1++; } start = p1; // ignore duplicates p0 = text.indexOf(AS_TEXT_BLOCK_SEPARATOR, start); while (p0 != -1 && p0 == start) { start += AS_TEXT_BLOCK_SEPARATOR_LENGTH; p0 = text.indexOf(AS_TEXT_BLOCK_SEPARATOR, start); } } if (start < length) { result.append(text.substring(start)); } return result.toString(); } protected void appendNode(final DomNode node) { if (node instanceof DomText) { appendText((DomText) node); } else if (node instanceof DomComment) { // nothing to do } else if ((node instanceof HtmlApplet) && appletEnabled_) { // nothing } else if (node instanceof HtmlBreak) { doAppendNewLine(); } else if (node instanceof HtmlHiddenInput || node instanceof HtmlScript || node instanceof HtmlStyle || node instanceof HtmlNoFrames) { // nothing } else if (node instanceof HtmlTextArea) { appendHtmlTextArea((HtmlTextArea) node); } else if (node instanceof HtmlTitle) { appendHtmlTitle((HtmlTitle) node); } else if (node instanceof HtmlTableRow) { appendHtmlTableRow((HtmlTableRow) node); } else if (node instanceof HtmlSelect) { appendHtmlSelect((HtmlSelect) node); } else if (node instanceof HtmlSubmitInput) { appendHtmlSubmitInput((HtmlSubmitInput) node); } else if (node instanceof HtmlCheckBoxInput) { final String str; if (((HtmlCheckBoxInput) node).isChecked()) { str = "checked"; } else { str = "unchecked"; } doAppend(str); } else if (node instanceof HtmlRadioButtonInput) { final String str; if (((HtmlRadioButtonInput) node).isChecked()) { str = "checked"; } else { str = "unchecked"; } doAppend(str); } else if (node instanceof HtmlInput) { doAppend(((HtmlInput) node).getValueAttribute()); } else if (node instanceof HtmlTable) { appendHtmlTable((HtmlTable) node); } else if (node instanceof HtmlOrderedList) { appendHtmlOrderedList((HtmlOrderedList) node); } else if (node instanceof HtmlUnorderedList) { appendHtmlUnorderedList((HtmlUnorderedList) node); } else if (node instanceof HtmlPreformattedText) { appendHtmlPreformattedText((HtmlPreformattedText) node); } else if (node instanceof HtmlNoScript && node.getPage().getWebClient().getOptions().isJavaScriptEnabled()) { return; } else { final boolean block = node.isBlock(); if (block) { doAppendBlockSeparator(); } appendChildren(node); if (block) { doAppendBlockSeparator(); } } } private void doAppendBlockSeparator() { buffer_.append(AS_TEXT_BLOCK_SEPARATOR); } private void doAppend(final String str) { buffer_.append(str); } private void doAppendNewLine() { buffer_.append(AS_TEXT_NEW_LINE); } private void doAppendTab() { buffer_.append(AS_TEXT_TAB); } private void appendHtmlUnorderedList(final HtmlUnorderedList htmlUnorderedList) { doAppendBlockSeparator(); boolean first = true; for (final DomNode item : htmlUnorderedList.getChildren()) { if (!first) { doAppendBlockSeparator(); } first = false; appendNode(item); } doAppendBlockSeparator(); } private void appendHtmlTitle(final HtmlTitle htmlTitle) { // optimized version // for the title there is no need to check the visibility // of the containing dom text; // this optimization defers the load of the style sheets final DomNode child = htmlTitle.getFirstChild(); if (child instanceof DomText) { doAppend(((DomText) child).getData()); doAppendBlockSeparator(); return; } } private void appendChildren(final DomNode node) { for (final DomNode child : node.getChildren()) { appendNode(child); } } private void appendHtmlTableRow(final HtmlTableRow htmlTableRow) { boolean first = true; for (final HtmlTableCell cell : htmlTableRow.getCells()) { if (!first) { doAppendTab(); } else { first = false; } appendChildren(cell); // trim? } } private void appendHtmlTextArea(final HtmlTextArea htmlTextArea) { if (isVisible(htmlTextArea)) { String text = htmlTextArea.getText(); final BrowserVersion browser = htmlTextArea.getPage().getWebClient().getBrowserVersion(); if (browser.hasFeature(HTMLTEXTAREA_REMOVE_NEWLINE_FROM_TEXT)) { text = TEXT_AREA_PATTERN.matcher(text).replaceAll(""); text = StringUtils.replace(text, "\r", ""); text = StringUtils.normalizeSpace(text); } else { text = StringUtils.stripEnd(text, null); text = TEXT_AREA_PATTERN.matcher(text).replaceAll(AS_TEXT_NEW_LINE); text = StringUtils.replace(text, "\r", AS_TEXT_NEW_LINE); } text = StringUtils.replace(text, " ", AS_TEXT_BLANK); doAppend(text); } } private void appendHtmlTable(final HtmlTable htmlTable) { doAppendBlockSeparator(); final String caption = htmlTable.getCaptionText(); if (caption != null) { doAppend(caption); doAppendBlockSeparator(); } boolean first = true; // first thead has to be displayed first and first tfoot has to be displayed last final HtmlTableHeader tableHeader = htmlTable.getHeader(); if (tableHeader != null) { first = appendHtmlTableRows(tableHeader.getRows(), true, null, null); } final HtmlTableFooter tableFooter = htmlTable.getFooter(); first = appendHtmlTableRows(htmlTable.getRows(), first, tableHeader, tableFooter); if (tableFooter != null) { first = appendHtmlTableRows(tableFooter.getRows(), first, null, null); } doAppendBlockSeparator(); } private boolean appendHtmlTableRows(final List<HtmlTableRow> rows, boolean first, final TableRowGroup skipParent1, final TableRowGroup skipParent2) { for (final HtmlTableRow row : rows) { if (row.getParentNode() == skipParent1 || row.getParentNode() == skipParent2) { continue; } if (!first) { doAppendBlockSeparator(); } first = false; appendHtmlTableRow(row); } return first; } private void appendHtmlSubmitInput(final HtmlSubmitInput htmlSubmitInput) { String value = htmlSubmitInput.getValueAttribute(); if (value == DomElement.ATTRIBUTE_NOT_DEFINED) { value = "Submit Query"; } doAppend(value); } /** * @param htmlSelect */ private void appendHtmlSelect(final HtmlSelect htmlSelect) { final List<HtmlOption> options; if (htmlSelect.isMultipleSelectEnabled()) { options = htmlSelect.getOptions(); } else { options = htmlSelect.getSelectedOptions(); } for (final Iterator<HtmlOption> i = options.iterator(); i.hasNext();) { final HtmlOption currentOption = i.next(); appendNode(currentOption); if (i.hasNext()) { doAppendBlockSeparator(); } } } /** * Appends a <ol> taking care to numerate it. * @param htmlOrderedList the OL element */ private void appendHtmlOrderedList(final HtmlOrderedList htmlOrderedList) { doAppendBlockSeparator(); boolean first = true; int i = 1; for (final DomNode item : htmlOrderedList.getChildren()) { if (!(item instanceof HtmlListItem)) { continue; } if (!first) { doAppendBlockSeparator(); } first = false; doAppend(Integer.toString(i++)); doAppend(". "); appendChildren(item); } doAppendBlockSeparator(); } private void appendHtmlPreformattedText(final HtmlPreformattedText htmlPreformattedText) { if (isVisible(htmlPreformattedText)) { doAppendBlockSeparator(); String text = htmlPreformattedText.getTextContent(); text = StringUtils.replace(text, "\t", AS_TEXT_TAB); text = StringUtils.replace(text, " ", AS_TEXT_BLANK); text = TEXT_AREA_PATTERN.matcher(text).replaceAll(AS_TEXT_NEW_LINE); text = StringUtils.replace(text, "\r", AS_TEXT_NEW_LINE); doAppend(text); doAppendBlockSeparator(); } } private void appendText(final DomText domText) { final DomNode parent = domText.getParentNode(); if (parent == null || parent instanceof HtmlTitle || isVisible(parent)) { append(domText.getData()); } } private boolean isVisible(final DomNode node) { return !ignoreMaskedElements_ || node.isDisplayed(); } /** * Indicates if element that are not displayed due to style settings * (visibility or display) should be visible in generated text. * @param ignore indicates if masked elements should be ignored or not */ public void setIgnoreMaskedElements(final boolean ignore) { ignoreMaskedElements_ = ignore; } private void append(final String text) { doAppend(text); } }