| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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 org.apache.hadoop.yarn.webapp.hamlet; |
| |
| import com.google.common.base.Joiner; |
| import static com.google.common.base.Preconditions.*; |
| import com.google.common.base.Splitter; |
| import com.google.common.collect.Iterables; |
| |
| import java.io.PrintWriter; |
| import java.util.EnumSet; |
| import static java.util.EnumSet.*; |
| import java.util.Iterator; |
| |
| import static org.apache.commons.lang.StringEscapeUtils.*; |
| import static org.apache.hadoop.yarn.webapp.hamlet.HamletImpl.EOpt.*; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.yarn.webapp.SubView; |
| import org.apache.hadoop.yarn.webapp.WebAppException; |
| |
| |
| /** |
| * A simple unbuffered generic hamlet implementation. |
| * |
| * Zero copy but allocation on every element, which could be |
| * optimized to use a thread-local element pool. |
| * |
| * Prints HTML as it builds. So the order is important. |
| */ |
| @InterfaceAudience.Private |
| public class HamletImpl extends HamletSpec { |
| private static final String INDENT_CHARS = " "; |
| private static final Splitter SS = Splitter.on('.'). |
| omitEmptyStrings().trimResults(); |
| private static final Joiner SJ = Joiner.on(' '); |
| private static final Joiner CJ = Joiner.on(", "); |
| static final int S_ID = 0; |
| static final int S_CLASS = 1; |
| |
| int nestLevel; |
| int indents; // number of indent() called. mostly for testing. |
| private final PrintWriter out; |
| private final StringBuilder sb = new StringBuilder(); // not shared |
| private boolean wasInline = false; |
| |
| /** |
| * Element options. (whether it needs end tag, is inline etc.) |
| */ |
| public enum EOpt { |
| /** needs end(close) tag */ |
| ENDTAG, |
| /** The content is inline */ |
| INLINE, |
| /** The content is preformatted */ |
| PRE |
| }; |
| |
| /** |
| * The base class for elements |
| * @param <T> type of the parent (containing) element for the element |
| */ |
| public class EImp<T extends _> implements _Child { |
| private final String name; |
| private final T parent; // short cut for parent element |
| private final EnumSet<EOpt> opts; // element options |
| |
| private boolean started = false; |
| private boolean attrsClosed = false; |
| |
| EImp(String name, T parent, EnumSet<EOpt> opts) { |
| this.name = name; |
| this.parent = parent; |
| this.opts = opts; |
| } |
| |
| @Override |
| public T _() { |
| closeAttrs(); |
| --nestLevel; |
| printEndTag(name, opts); |
| return parent; |
| } |
| |
| protected void _p(boolean quote, Object... args) { |
| closeAttrs(); |
| for (Object s : args) { |
| if (!opts.contains(PRE)) { |
| indent(opts); |
| } |
| out.print(quote ? escapeHtml(String.valueOf(s)) |
| : String.valueOf(s)); |
| if (!opts.contains(INLINE) && !opts.contains(PRE)) { |
| out.println(); |
| } |
| } |
| } |
| |
| protected void _v(Class<? extends SubView> cls) { |
| closeAttrs(); |
| subView(cls); |
| } |
| |
| protected void closeAttrs() { |
| if (!attrsClosed) { |
| startIfNeeded(); |
| ++nestLevel; |
| out.print('>'); |
| if (!opts.contains(INLINE) && !opts.contains(PRE)) { |
| out.println(); |
| } |
| attrsClosed = true; |
| } |
| } |
| |
| protected void addAttr(String name, String value) { |
| checkState(!attrsClosed, "attribute added after content"); |
| startIfNeeded(); |
| printAttr(name, value); |
| } |
| |
| protected void addAttr(String name, Object value) { |
| addAttr(name, String.valueOf(value)); |
| } |
| |
| protected void addMediaAttr(String name, EnumSet<Media> media) { |
| // 6.13 comma-separated list |
| addAttr(name, CJ.join(media)); |
| } |
| |
| protected void addRelAttr(String name, EnumSet<LinkType> types) { |
| // 6.12 space-separated list |
| addAttr(name, SJ.join(types)); |
| } |
| |
| private void startIfNeeded() { |
| if (!started) { |
| printStartTag(name, opts); |
| started = true; |
| } |
| } |
| |
| protected void _inline(boolean choice) { |
| if (choice) { |
| opts.add(INLINE); |
| } else { |
| opts.remove(INLINE); |
| } |
| } |
| |
| protected void _endTag(boolean choice) { |
| if (choice) { |
| opts.add(ENDTAG); |
| } else { |
| opts.remove(ENDTAG); |
| } |
| } |
| |
| protected void _pre(boolean choice) { |
| if (choice) { |
| opts.add(PRE); |
| } else { |
| opts.remove(PRE); |
| } |
| } |
| } |
| |
| public class Generic<T extends _> extends EImp<T> implements PCData { |
| Generic(String name, T parent, EnumSet<EOpt> opts) { |
| super(name, parent, opts); |
| } |
| |
| public Generic<T> _inline() { |
| super._inline(true); |
| return this; |
| } |
| |
| public Generic<T> _noEndTag() { |
| super._endTag(false); |
| return this; |
| } |
| |
| public Generic<T> _pre() { |
| super._pre(true); |
| return this; |
| } |
| |
| public Generic<T> _attr(String name, String value) { |
| addAttr(name, value); |
| return this; |
| } |
| |
| public Generic<Generic<T>> _elem(String name, EnumSet<EOpt> opts) { |
| closeAttrs(); |
| return new Generic<Generic<T>>(name, this, opts); |
| } |
| |
| public Generic<Generic<T>> elem(String name) { |
| return _elem(name, of(ENDTAG)); |
| } |
| |
| @Override |
| public Generic<T> _(Object... lines) { |
| _p(true, lines); |
| return this; |
| } |
| |
| @Override |
| public Generic<T> _r(Object... lines) { |
| _p(false, lines); |
| return this; |
| } |
| } |
| |
| public HamletImpl(PrintWriter out, int nestLevel, boolean wasInline) { |
| this.out = out; |
| this.nestLevel = nestLevel; |
| this.wasInline = wasInline; |
| } |
| |
| public int nestLevel() { |
| return nestLevel; |
| } |
| |
| public boolean wasInline() { |
| return wasInline; |
| } |
| |
| public void setWasInline(boolean state) { |
| wasInline = state; |
| } |
| |
| public PrintWriter getWriter() { |
| return out; |
| } |
| |
| /** |
| * Create a root-level generic element. |
| * Mostly for testing purpose. |
| * @param <T> type of the parent element |
| * @param name of the element |
| * @param opts {@link EOpt element options} |
| * @return the element |
| */ |
| public <T extends _> |
| Generic<T> root(String name, EnumSet<EOpt> opts) { |
| return new Generic<T>(name, null, opts); |
| } |
| |
| public <T extends _> Generic<T> root(String name) { |
| return root(name, of(ENDTAG)); |
| } |
| |
| protected void printStartTag(String name, EnumSet<EOpt> opts) { |
| indent(opts); |
| sb.setLength(0); |
| out.print(sb.append('<').append(name).toString()); // for easier mock test |
| } |
| |
| protected void indent(EnumSet<EOpt> opts) { |
| if (opts.contains(INLINE) && wasInline) { |
| return; |
| } |
| if (wasInline) { |
| out.println(); |
| } |
| wasInline = opts.contains(INLINE) || opts.contains(PRE); |
| for (int i = 0; i < nestLevel; ++i) { |
| out.print(INDENT_CHARS); |
| } |
| ++indents; |
| } |
| |
| protected void printEndTag(String name, EnumSet<EOpt> opts) { |
| if (!opts.contains(ENDTAG)) { |
| return; |
| } |
| if (!opts.contains(PRE)) { |
| indent(opts); |
| } else { |
| wasInline = opts.contains(INLINE); |
| } |
| sb.setLength(0); |
| out.print(sb.append("</").append(name).append('>').toString()); // ditto |
| if (!opts.contains(INLINE)) { |
| out.println(); |
| } |
| } |
| |
| protected void printAttr(String name, String value) { |
| sb.setLength(0); |
| sb.append(' ').append(name); |
| if (value != null) { |
| sb.append("=\"").append(escapeHtml(value)).append("\""); |
| } |
| out.print(sb.toString()); |
| } |
| |
| /** |
| * Sub-classes should override this to do something interesting. |
| * @param cls the sub-view class |
| */ |
| protected void subView(Class<? extends SubView> cls) { |
| indent(of(ENDTAG)); // not an inline view |
| sb.setLength(0); |
| out.print(sb.append('[').append(cls.getName()).append(']').toString()); |
| out.println(); |
| } |
| |
| /** |
| * Parse selector into id and classes |
| * @param selector in the form of (#id)?(.class)* |
| * @return an two element array [id, "space-separated classes"]. |
| * Either element could be null. |
| * @throws WebAppException when both are null or syntax error. |
| */ |
| public static String[] parseSelector(String selector) { |
| String[] result = new String[]{null, null}; |
| Iterable<String> rs = SS.split(selector); |
| Iterator<String> it = rs.iterator(); |
| if (it.hasNext()) { |
| String maybeId = it.next(); |
| if (maybeId.charAt(0) == '#') { |
| result[S_ID] = maybeId.substring(1); |
| if (it.hasNext()) { |
| result[S_CLASS] = SJ.join(Iterables.skip(rs, 1)); |
| } |
| } else { |
| result[S_CLASS] = SJ.join(rs); |
| } |
| return result; |
| } |
| throw new WebAppException("Error parsing selector: "+ selector); |
| } |
| |
| /** |
| * Set id and/or class attributes for an element. |
| * @param <E> type of the element |
| * @param e the element |
| * @param selector Haml form of "(#id)?(.class)*" |
| * @return the element |
| */ |
| public static <E extends CoreAttrs> E setSelector(E e, String selector) { |
| String[] res = parseSelector(selector); |
| if (res[S_ID] != null) { |
| e.$id(res[S_ID]); |
| } |
| if (res[S_CLASS] != null) { |
| e.$class(res[S_CLASS]); |
| } |
| return e; |
| } |
| |
| public static <E extends LINK> E setLinkHref(E e, String href) { |
| if (href.endsWith(".css")) { |
| e.$rel("stylesheet"); // required in html5 |
| } |
| e.$href(href); |
| return e; |
| } |
| |
| public static <E extends SCRIPT> E setScriptSrc(E e, String src) { |
| if (src.endsWith(".js")) { |
| e.$type("text/javascript"); // required in html4 |
| } |
| e.$src(src); |
| return e; |
| } |
| } |