8266779: Use <wbr> instead of ZERO_WIDTH_SPACE

Reviewed-by: prappo

src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/formats/html/AbstractExecutableMemberWriter.java

@@ -41,6 +41,7 @@
 import jdk.javadoc.internal.doclets.formats.html.markup.Entity;
 import jdk.javadoc.internal.doclets.formats.html.markup.HtmlStyle;
 import jdk.javadoc.internal.doclets.formats.html.markup.HtmlTree;
+import jdk.javadoc.internal.doclets.formats.html.markup.TagName;
 import jdk.javadoc.internal.doclets.toolkit.Content;
 import jdk.javadoc.internal.doclets.toolkit.util.DocletConstants;
 
@@ -91,7 +92,7 @@ protected Content getSummaryLink(Element member) {
         }
         String signature = utils.flatSignature((ExecutableElement) member, typeElement);
         if (signature.length() > 2) {
-            content.add(Entity.ZERO_WIDTH_SPACE);
+            content.add(new HtmlTree(TagName.WBR));
         }
         content.add(signature);
 
@@ -209,8 +210,8 @@ public Boolean visitDeclared(DeclaredType t, Void unused) {
     protected void addParameters(ExecutableElement member, Content htmltree) {
         Content paramTree = getParameters(member, false);
         if (paramTree.charCount() > 2) {
-            // only add zero-width-space for non-empty parameters
-            htmltree.add(Entity.ZERO_WIDTH_SPACE);
+            // only add <wbr> for non-empty parameters
+            htmltree.add(new HtmlTree(TagName.WBR));
         }
         htmltree.add(paramTree);
     }

src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/formats/html/HtmlLinkFactory.java

@@ -37,8 +37,8 @@
 import javax.lang.model.type.TypeMirror;
 
 import jdk.javadoc.internal.doclets.formats.html.markup.ContentBuilder;
-import jdk.javadoc.internal.doclets.formats.html.markup.Entity;
 import jdk.javadoc.internal.doclets.formats.html.markup.HtmlTree;
+import jdk.javadoc.internal.doclets.formats.html.markup.TagName;
 import jdk.javadoc.internal.doclets.toolkit.BaseConfiguration;
 import jdk.javadoc.internal.doclets.toolkit.Content;
 import jdk.javadoc.internal.doclets.toolkit.Resources;
@@ -171,7 +171,7 @@ protected Content getTypeParameterLinks(LinkInfo linkInfo) {
             for (TypeMirror t : vars) {
                 if (many) {
                     links.add(",");
-                    links.add(Entity.ZERO_WIDTH_SPACE);
+                    links.add(new HtmlTree(TagName.WBR));
                     if (((HtmlLinkInfo) linkInfo).getContext() == HtmlLinkInfo.Kind.MEMBER_TYPE_PARAMS) {
                         links.add(DocletConstants.NL);
                     }

src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/formats/html/Signatures.java

@@ -457,7 +457,7 @@ private void appendParametersAndExceptions(Content htmlTree, int lastLineSeparat
                 // empty parameters are added without packing
                 htmlTree.add(parameters);
             } else {
-                htmlTree.add(Entity.ZERO_WIDTH_SPACE)
+                htmlTree.add(new HtmlTree(TagName.WBR))
                         .add(HtmlTree.SPAN(HtmlStyle.parameters, parameters));
             }
 

src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/formats/html/markup/Entity.java

@@ -38,12 +38,6 @@ public class Entity extends Content {
     public static final Entity GREATER_THAN = new Entity(">");
     public static final Entity AMPERSAND = new Entity("&");
     public static final Entity NO_BREAK_SPACE = new Entity(" ");
-    public static final Entity ZERO_WIDTH_SPACE = new Entity("​") {
-        @Override
-        public int charCount() {
-            return 0;
-        }
-    };
 
     public final String text;
 

src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/formats/html/markup/HtmlTree.java

@@ -926,6 +926,8 @@ public boolean isValid() {
                         (hasAttr(HtmlAttr.TYPE) && hasContent()));
             case SPAN:
                 return (hasAttr(HtmlAttr.ID) || hasContent());
+            case WBR:
+                return (!hasContent());
             default :
                 return hasContent();
         }
@@ -942,6 +944,7 @@ public boolean isInline() {
         switch (tagName) {
             case A: case BUTTON: case BR: case CODE: case EM: case I: case IMG:
             case LABEL: case SMALL: case SPAN: case STRONG: case SUB: case SUP:
+            case WBR:
                 return true;
             default:
                 return false;
@@ -957,7 +960,7 @@ public boolean isInline() {
      */
     public boolean isVoid() {
         switch (tagName) {
-            case BR: case HR: case IMG: case INPUT: case LINK: case META:
+            case BR: case HR: case IMG: case INPUT: case LINK: case META: case WBR:
                 return true;
             default:
                 return false;

src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/formats/html/markup/TagName.java

@@ -91,7 +91,8 @@ public enum TagName {
     TH,
     TITLE,
     TR,
-    UL;
+    UL,
+    WBR;
 
     public final String value;
 

test/langtools/jdk/javadoc/doclet/testConstructors/TestConstructors.java

@@ -69,7 +69,7 @@ public void test() {
                 """
                     <section class="detail" id="&lt;init&gt;()">""",
                 """
-                    <a href="#%3Cinit%3E(int)" class="member-name-link">Outer</a>&#8203;(int&nbsp;i)""",
+                    <a href="#%3Cinit%3E(int)" class="member-name-link">Outer</a><wbr>(int&nbsp;i)""",
                 """
                     <section class="detail" id="&lt;init&gt;(int)">""");
 
@@ -79,7 +79,7 @@ public void test() {
                 """
                     <section class="detail" id="&lt;init&gt;()">""",
                 """
-                    <a href="#%3Cinit%3E(int)" class="member-name-link">Inner</a>&#8203;(int&nbsp;i)""",
+                    <a href="#%3Cinit%3E(int)" class="member-name-link">Inner</a><wbr>(int&nbsp;i)""",
                 """
                     <section class="detail" id="&lt;init&gt;(int)">""");
 
@@ -89,7 +89,7 @@ public void test() {
                 """
                     <section class="detail" id="&lt;init&gt;()">""",
                 """
-                    <a href="#%3Cinit%3E(int)" class="member-name-link">NestedInner</a>&#8203;(int&nbsp;i)""",
+                    <a href="#%3Cinit%3E(int)" class="member-name-link">NestedInner</a><wbr>(int&nbsp;i)""",
                 """
                     <section class="detail" id="&lt;init&gt;(int)">""");
 

test/langtools/jdk/javadoc/doclet/testDeprecatedDocs/TestDeprecatedDocs.java

@@ -355,11 +355,11 @@ public void test() {
                     <div class="col-last odd-row-color">
                     <div class="deprecation-comment">class_test5 passes. This is the second sentence of deprecated description for a method.</div>
                     </div>
-                    <div class="col-summary-item-name even-row-color"><a href="pkg/TestClass.html#overloadedMethod(int)">pkg.TestClass.overloadedMethod&#8203;(int)</a></div>
+                    <div class="col-summary-item-name even-row-color"><a href="pkg/TestClass.html#overloadedMethod(int)">pkg.TestClass.overloadedMethod<wbr>(int)</a></div>
                     <div class="col-last even-row-color">
                     <div class="deprecation-comment">class_test7 passes. Overloaded method 2.</div>
                     </div>
-                    <div class="col-summary-item-name odd-row-color"><a href="pkg/TestClass.html#overloadedMethod(java.lang.String)">pkg.TestClass.overloadedMethod&#8203;(String)</a></div>
+                    <div class="col-summary-item-name odd-row-color"><a href="pkg/TestClass.html#overloadedMethod(java.lang.String)">pkg.TestClass.overloadedMethod<wbr>(String)</a></div>
                     <div class="col-last odd-row-color">
                     <div class="deprecation-comment">class_test6 passes. Overloaded method 1.</div>
                     </div>""",
@@ -375,7 +375,7 @@ public void test() {
                     <div class="col-last odd-row-color">
                     <div class="deprecation-comment">class_test3 passes. This is the second sentence of deprecated description for a constructor.</div>
                     </div>
-                    <div class="col-summary-item-name even-row-color"><a href="pkg/TestClass.html#%3Cinit%3E(java.lang.String)">pkg.TestClass&#8203;(String)</a></div>
+                    <div class="col-summary-item-name even-row-color"><a href="pkg/TestClass.html#%3Cinit%3E(java.lang.String)">pkg.TestClass<wbr>(String)</a></div>
                     <div class="col-last even-row-color">
                     <div class="deprecation-comment">class_test4 passes. Overloaded constructor.</div>
                     </div>""");

test/langtools/jdk/javadoc/doclet/testEnumConstructor/TestEnumConstructor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -68,7 +68,7 @@ public void test1(Path base) throws Exception {
                 "Constructor Summary",
                 "Modifier", "Constructor",
                 "private", """
-                    <a href="#%3Cinit%3E(int)" class="member-name-link">TestEnum</a>&#8203;(int&nbsp;val)""");
+                    <a href="#%3Cinit%3E(int)" class="member-name-link">TestEnum</a><wbr>(int&nbsp;val)""");
         checkOutput("index-all.html", true,
                 """
                     <a href="pkg/TestEnum.html#%3Cinit%3E(int)" class="member-name-link">TestEnum(int)</a>""");

test/langtools/jdk/javadoc/doclet/testGenericTypeLink/TestGenericTypeLink.java

@@ -74,18 +74,18 @@ r interface in java.util" class="external-link">List</a>&lt;? extends <a href="h
                     <li><code><a href="http://example.com/docs/api/java.base/java/util/Map.html" title="\
                     class or interface in java.util" class="external-link">Map</a>&lt;<a href="http://ex\
                     ample.com/docs/api/java.base/java/lang/String.html" title="class or interface in jav\
-                    a.lang" class="external-link">String</a>,&#8203;? extends <a href="http://example.co\
-                    m/docs/api/java.base/java/lang/CharSequence.html" title="class or interface in java.\
-                    lang" class="external-link">CharSequence</a>&gt;</code></li>
+                    a.lang" class="external-link">String</a>,<wbr>? extends <a href="http://example.com/\
+                    docs/api/java.base/java/lang/CharSequence.html" title="class or interface in java.la\
+                    ng" class="external-link">CharSequence</a>&gt;</code></li>
                     <li><code><a href="http://example.com/docs/api/java.base/java/util/Map.html" title="\
                     class or interface in java.util" class="external-link">Map</a>&lt;<a href="http://ex\
                     ample.com/docs/api/java.base/java/lang/String.html" title="class or interface in jav\
-                    a.lang" class="external-link">String</a>,&#8203;? super <a href="A.html" title="clas\
-                    s in pkg1">A</a>&lt;<a href="http://example.com/docs/api/java.base/java/lang/String.\
-                    html" title="class or interface in java.lang" class="external-link">String</a>,&#820\
-                    3;? extends <a href="http://example.com/docs/api/java.base/java/lang/RuntimeExceptio\
-                    n.html" title="class or interface in java.lang" class="external-link">RuntimeExcepti\
-                    on</a>&gt;&gt;</code></li>
+                    a.lang" class="external-link">String</a>,<wbr>? super <a href="A.html" title="class \
+                    in pkg1">A</a>&lt;<a href="http://example.com/docs/api/java.base/java/lang/String.ht\
+                    ml" title="class or interface in java.lang" class="external-link">String</a>,<wbr>? \
+                    extends <a href="http://example.com/docs/api/java.base/java/lang/RuntimeException.ht\
+                    ml" title="class or interface in java.lang" class="external-link">RuntimeException</\
+                    a>&gt;&gt;</code></li>
                     <li><a href="#someMethod(java.util.List,int)"><code>someMethod(List&lt;Number&gt;, i\
                     nt)</code></a></li>
                     <li><a href="#otherMethod(java.util.Map,double)"><code>otherMethod(Map&lt;String, ? \
@@ -97,8 +97,8 @@ class or interface in java.util" class="external-link">Map</a>&lt;<a href="http:
                 """
                     <div class="block"><code><a href="A.html" title="class in pkg1">A</a>&lt;<a href="h\
                     ttp://example.com/docs/api/java.base/java/lang/String.html" title="class or interfa\
-                    ce in java.lang" class="external-link">String</a>,&#8203;<a href="A.SomeException.h\
-                    tml" title="class in pkg1">A.SomeException</a>&gt;</code>
+                    ce in java.lang" class="external-link">String</a>,<wbr><a href="A.SomeException.htm\
+                    l" title="class in pkg1">A.SomeException</a>&gt;</code>
                      <a href="http://example.com/docs/api/java.base/java/util/Map.html" title="class or\
                      interface in java.util" class="external-link">link to generic type with label</a>\
                     </div>""",
@@ -109,8 +109,8 @@ interface in java.util" class="external-link">link to generic type with label</a
                     <ul class="see-list-long">
                     <li><code><a href="A.html" title="class in pkg1">A</a>&lt;<a href="http://example.c\
                     om/docs/api/java.base/java/lang/String.html" title="class or interface in java.lang\
-                    " class="external-link">String</a>,&#8203;<a href="A.SomeException.html" title="cla\
-                    ss in pkg1">A.SomeException</a>&gt;</code></li>
+                    " class="external-link">String</a>,<wbr><a href="A.SomeException.html" title="class\
+                     in pkg1">A.SomeException</a>&gt;</code></li>
                     <li><a href="http://example.com/docs/api/java.base/java/util/List.html" title="clas\
                     s or interface in java.util" class="external-link"><code>Link to generic type with \
                     label</code></a></li>

test/langtools/jdk/javadoc/doclet/testHtmlTableTags/TestHtmlTableTags.java

@@ -611,7 +611,7 @@ void checkHtmlTableContents() {
                     ab2 method-summary-table-tab4"><code>void</code></div>
                     <div class="col-second even-row-color method-summary-table method-summary-table-\
                     tab2 method-summary-table-tab4"><code><a href="#method1(int,int)" class="member-\
-                    name-link">method1</a>&#8203;(int&nbsp;a,
+                    name-link">method1</a><wbr>(int&nbsp;a,
                      int&nbsp;b)</code></div>
                     <div class="col-last even-row-color method-summary-table method-summary-table-ta\
                     b2 method-summary-table-tab4">
@@ -631,8 +631,8 @@ void checkHtmlTableContents() {
                     kg1">C1</a></code></div>
                     <div class="col-second even-row-color method-summary-table method-summary-table-\
                     tab2 method-summary-table-tab4"><code><a href="#method(pkg1.C1)" class="member-n\
-                    ame-link">method</a>&#8203;(<a href="../pkg1/C1.html" title="class \
-                    in pkg1">C1</a>&nbsp;param)</code></div>
+                    ame-link">method</a><wbr>(<a href="../pkg1/C1.html" title="class in pkg1">C1</a>\
+                    &nbsp;param)</code></div>
                     <div class="col-last even-row-color method-summary-table method-summary-table-ta\
                     b2 method-summary-table-tab4">
                     <div class="block">A sample method.</div>
@@ -680,8 +680,8 @@ void checkHtmlTableContents() {
                     <div class="col-first even-row-color"><code><a href="../C2.html" title="class in pkg2">C2</a></code></div>
                     <div class="col-second even-row-color"><span class="type-name-label">C1.</span><\
                     code><a href="../../pkg1/C1.html#method(pkg2.C2)" class="member-name-link">metho\
-                    d</a>&#8203;(<a href="../C2.html" title="class in pkg2">C2</a>&nbsp\
-                    ;param)</code></div>
+                    d</a><wbr>(<a href="../C2.html" title="class in pkg2">C2</a>&nbsp;param)</code><\
+                    /div>
                     <div class="col-last even-row-color">
                     <div class="block">Method thats does some processing.</div>
                     </div>""");
@@ -769,7 +769,7 @@ void checkHtmlTableContentsNoComment() {
                     ab2 method-summary-table-tab4"><code>void</code></div>
                     <div class="col-second even-row-color method-summary-table method-summary-table-\
                     tab2 method-summary-table-tab4"><code><a href="#method1(int,int)" class="member-\
-                    name-link">method1</a>&#8203;(int&nbsp;a,
+                    name-link">method1</a><wbr>(int&nbsp;a,
                      int&nbsp;b)</code></div>
                     <div class="col-last even-row-color method-summary-table method-summary-table-ta\
                     b2 method-summary-table-tab4"></div>""");
@@ -785,8 +785,8 @@ void checkHtmlTableContentsNoComment() {
                     kg1">C1</a></code></div>
                     <div class="col-second even-row-color method-summary-table method-summary-table-\
                     tab2 method-summary-table-tab4"><code><a href="#method(pkg1.C1)" class="member-n\
-                    ame-link">method</a>&#8203;(<a href="../pkg1/C1.html" title="class in pkg1">C1</\
-                    a>&nbsp;param)</code></div>
+                    ame-link">method</a><wbr>(<a href="../pkg1/C1.html" title="class in pkg1">C1</a>\
+                    &nbsp;param)</code></div>
                     <div class="col-last even-row-color method-summary-table method-summary-table-ta\
                     b2 method-summary-table-tab4"></div>""");
 
@@ -827,7 +827,7 @@ void checkHtmlTableContentsNoComment() {
                     <div class="col-first even-row-color"><code><a href="../C2.html" title="class in pkg2">C2</a></code></div>
                     <div class="col-second even-row-color"><span class="type-name-label">C1.</span><\
                     code><a href="../../pkg1/C1.html#method(pkg2.C2)" class="member-name-link">metho\
-                    d</a>&#8203;(<a href="../C2.html" title="class in pkg2">C2</a>&nbsp;param)</code></div>
+                    d</a><wbr>(<a href="../C2.html" title="class in pkg2">C2</a>&nbsp;param)</code></div>
                     <div class="col-last even-row-color"></div>""");
 
         // Package use documentation

test/langtools/jdk/javadoc/doclet/testIndentation/TestIndentation.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -52,7 +52,7 @@ public void test() {
                 """
                     <div class="member-signature"><span class="modifiers">public</span>&nbsp;<span c\
                     lass="type-parameters">&lt;T&gt;</span>&nbsp;<span class="return-type">void</spa\
-                    n>&nbsp;<span class="element-name">m</span>&#8203;<span class="parameters">(T&nbsp;t1,
+                    n>&nbsp;<span class="element-name">m</span><wbr><span class="parameters">(T&nbsp;t1,
                      T&nbsp;t2)</span>
                                throws <span class="exceptions">java.lang.Exception</span></div>""");