Java tutorial
/* * Copyright 2015 Igor Maznitsa. * * 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.igormaznitsa.mindmap.model; import com.igormaznitsa.mindmap.model.logger.Logger; import com.igormaznitsa.mindmap.model.logger.LoggerFactory; import com.igormaznitsa.mindmap.model.nio.Path; import com.igormaznitsa.mindmap.model.nio.Paths; import java.io.File; import java.io.IOException; import java.io.UnsupportedEncodingException; import java.net.URI; import java.net.URISyntaxException; import java.net.URLDecoder; import java.net.URLEncoder; import java.util.ArrayList; import java.util.Arrays; import java.util.List; import java.util.Locale; import java.util.Properties; import java.util.regex.Matcher; import java.util.regex.Pattern; import javax.annotation.Nonnull; import javax.annotation.Nullable; import org.apache.commons.lang.StringEscapeUtils; import com.igormaznitsa.meta.annotation.MustNotContainNull; public final class ModelUtils { private ModelUtils() { } private static final Logger LOGGER = LoggerFactory.getLogger(ModelUtils.class); private static final Pattern UNESCAPE_BR = Pattern.compile("(?i)\\<\\s*?br\\s*?\\/?\\>"); //NOI18N private static final Pattern MD_ESCAPED_PATTERN = Pattern.compile("(\\\\[\\\\`*_{}\\[\\]()#<>+-.!])"); //NOI18N private static final String MD_ESCAPED_CHARS = "\\`*_{}[]()#<>+-.!"; //NOI18N private static final Pattern URI_QUERY_PARAMETERS = Pattern.compile("\\&?([^=]+)=([^&]*)"); //NOI18N public static int calcCharsOnStart(final char chr, @Nonnull final String text) { int result = 0; for (int i = 0; i < text.length(); i++) { if (text.charAt(i) == chr) { result++; } else { break; } } return result; } public static boolean onlyFromChar(@Nonnull final String line, final char chr) { if (line.isEmpty()) { return false; } for (int i = 0; i < line.length(); i++) { if (line.charAt(i) != chr) { return false; } } return true; } @Nonnull @MustNotContainNull public static Object[] joinArrays(@Nonnull @MustNotContainNull final Object[]... arrs) { int totalLen = 0; for (final Object[] a : arrs) { totalLen += a.length; } final Object[] result = new Object[totalLen]; int pos = 0; for (final Object[] a : arrs) { System.arraycopy(a, 0, result, pos, a.length); pos += a.length; } return result; } @Nonnull public static String makePreBlock(@Nonnull final String text) { return "<pre>" + StringEscapeUtils.escapeHtml(text) + "</pre>"; //NOI18N } @Nonnull public static String makeMDCodeBlock(@Nonnull final String text) throws IOException { final int maxQuotes = calcMaxLengthOfBacktickQuotesSubstr(text) + 1; final StringBuilder result = new StringBuilder(text.length() + 16); writeChar(result, '`', maxQuotes); result.append(text); writeChar(result, '`', maxQuotes); return result.toString(); } @Nonnull public static String escapeMarkdownStr(@Nonnull final String text) { final StringBuilder buffer = new StringBuilder(text.length() * 2); for (final char c : text.toCharArray()) { if (c == '\n') { buffer.append("<br/>"); //NOI18N continue; } else if (Character.isISOControl(c)) { continue; } else if (MD_ESCAPED_CHARS.indexOf(c) >= 0) { buffer.append('\\'); } buffer.append(c); } return buffer.toString(); } public static int calcMaxLengthOfBacktickQuotesSubstr(@Nullable final String text) { int result = 0; if (text != null) { int pos = 0; while (pos >= 0) { pos = text.indexOf('`', pos); if (pos >= 0) { int found = 0; while (pos < text.length() && text.charAt(pos) == '`') { found++; pos++; } result = Math.max(result, found); } } } return result; } public static void writeChar(@Nonnull final Appendable out, final char chr, final int times) throws IOException { for (int i = 0; i < times; i++) { out.append(chr); } } @Nonnull public static String unescapeMarkdownStr(@Nonnull final String text) { String unescaped = UNESCAPE_BR.matcher(text).replaceAll("\n"); //NOI18N final StringBuffer result = new StringBuffer(text.length()); final Matcher escaped = MD_ESCAPED_PATTERN.matcher(unescaped); while (escaped.find()) { final String group = escaped.group(1); escaped.appendReplacement(result, Matcher.quoteReplacement(group.substring(1))); } escaped.appendTail(result); return result.toString(); } @Nonnull public static String makeShortTextVersion(@Nonnull String text, final int maxLength) { if (text.length() > maxLength) { text = text.substring(0, maxLength) + "..."; //NOI18N } return text; } public static int countLines(@Nonnull final String text) { int result = 1; for (int i = 0; i < text.length(); i++) { if (text.charAt(i) == '\n') { result++; } } return result; } @Nonnull @MustNotContainNull public static String[] breakToLines(@Nonnull final String text) { final int lineNum = countLines(text); final String[] result = new String[lineNum]; final StringBuilder line = new StringBuilder(); int index = 0; for (int i = 0; i < text.length(); i++) { if (text.charAt(i) == '\n') { result[index++] = line.toString(); line.setLength(0); } else { line.append(text.charAt(i)); } } result[index] = line.toString(); return result; } @Nonnull public static String makeQueryStringForURI(@Nullable final Properties properties) { if (properties == null || properties.isEmpty()) { return ""; //NOI18N } final StringBuilder buffer = new StringBuilder(); for (final String k : properties.stringPropertyNames()) { try { final String encodedKey = URLEncoder.encode(k, "UTF-8"); //NOI18N final String encodedValue = URLEncoder.encode(properties.getProperty(k), "UTF-8"); //NOI18N if (buffer.length() > 0) { buffer.append('&'); } buffer.append(encodedKey).append('=').append(encodedValue); } catch (UnsupportedEncodingException ex) { LOGGER.error("Can't encode URI query", ex); //NOI18N throw new Error("Unexpected exception, can't find UTF-8 charset!"); //NOI18N } } return buffer.toString(); } @Nonnull public static Properties extractQueryPropertiesFromURI(@Nonnull final URI uri) { final Properties result = new Properties(); final String rawQuery = uri.getRawQuery(); if (rawQuery != null) { final Matcher matcher = URI_QUERY_PARAMETERS.matcher(rawQuery); try { while (matcher.find()) { final String key = URLDecoder.decode(matcher.group(1), "UTF-8"); //NOI18N final String value = URLDecoder.decode(matcher.group(2), "UTF-8"); //NOI18N result.put(key, value); } } catch (UnsupportedEncodingException ex) { LOGGER.error("Can't decode URI query", ex); //NOI18N throw new Error("Unexpected exception, can't find UTF-8 charset!"); //NOI18N } } return result; } @Nonnull private static String char2UriHexByte(final char ch) { final String s = Integer.toHexString(ch).toUpperCase(Locale.ENGLISH); return '%' + (s.length() < 2 ? "0" : "") + s; //NOI18N //NOI18N } @Nonnull public static String encodeForURI(@Nonnull final String s) { final StringBuilder result = new StringBuilder(); for (int i = 0; i < s.length(); i++) { final char c = s.charAt(i); if ((c >= '0' && c <= '9') || (c >= 'A' && c <= 'Z') || "-_.~".indexOf(c) >= 0) { //NOI18N result.append(c); } else { if (":/?#[]@!$^'()*+,;= ".indexOf(c) >= 0) { //NOI18N result.append(char2UriHexByte(c)); } else { result.append(c); } } } return result.toString(); } @Nullable public static File makeFileForPath(@Nullable final String path) { if (path == null || path.isEmpty()) { return null; } if (path.startsWith("file:")) { //NOI18N try { return new File(new URI(normalizeFileURI(path))); } catch (URISyntaxException ex) { LOGGER.error("URISyntaxException for " + path, ex); //NOI18N return null; } } else { return new File(path); } } @Nonnull public static String escapeURIPath(@Nonnull final String text) { final String chars = "% :<>?"; //NOI18N String result = text; for (final char ch : chars.toCharArray()) { result = result.replace(Character.toString(ch), "%" + Integer.toHexString(ch).toUpperCase(Locale.ENGLISH)); //NOI18N } return result; } @Nonnull private static String normalizeFileURI(@Nonnull final String fileUri) { final int schemePosition = fileUri.indexOf(':'); final String scheme = schemePosition < 0 ? "" : fileUri.substring(0, schemePosition + 1); //NOI18N final String chars = " :<>?"; //NOI18N String result = fileUri.substring(scheme.length()); for (final char ch : chars.toCharArray()) { result = result.replace(Character.toString(ch), "%" + Integer.toHexString(ch).toUpperCase(Locale.ENGLISH)); //NOI18N } return scheme + result; } @Nullable public static URI toURI(@Nullable final Path path) { if (path == null) { return null; } try { final StringBuilder buffer = new StringBuilder(); final Path root = path.getRoot(); if (root != null) { buffer.append(root.toString().replace('\\', '/')); } for (final Path p : path) { if (buffer.length() > 0 && buffer.charAt(buffer.length() - 1) != '/') { buffer.append('/'); } buffer.append(encodeForURI(p.toFile().getName())); } if (path.isAbsolute()) { buffer.insert(0, "file://" + (root == null ? "/" : "")); //NOI18N } return new URI(buffer.toString()); } catch (Exception ex) { throw new IllegalArgumentException("Can't convert path to URI: " + path, ex); //NOI18N } } @Nonnull public static File toFile(@Nonnull final URI uri) { final List<String> pathItems = new ArrayList<String>(); final String authority = uri.getAuthority(); if (authority != null && !authority.isEmpty()) { pathItems.add(authority); } final String[] splittedPath = uri.getPath().split("\\/"); boolean separator = false; if (splittedPath.length == 0) { separator = true; } else { for (final String s : splittedPath) { if (!s.isEmpty()) { pathItems.add(separator ? File.separatorChar + s : s); separator = false; } else { separator = true; } } } if (separator) { pathItems.add(File.separator); } final String[] fullArray = pathItems.toArray(new String[pathItems.size()]); final String[] next = Arrays.copyOfRange(fullArray, 1, fullArray.length); return Paths.get(fullArray[0], next).toFile(); } }