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Update to current. 

This includes changes for Java 8, and simplified import order rules.
1 parent f15e633 commit b075cb7cad464b224103fb2ec8fdb8521ec08e7f @cushon cushon committed Jul 12, 2016
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Showing with 35 additions and 31 deletions.
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66 javaguide.html
@@ -186,37 +186,21 @@ <h4 id="s3.3.2-import-line-wrapping">3.3.2 No line-wrapping</h4>
<h4 id="s3.3.3-import-ordering-and-spacing">3.3.3 Ordering and spacing</h4>
-
-
-<p>Import statements are divided into the following groups, in this order, with each group
-separated by a single blank line:</p>
+<p>Imports are ordered as follows:</p>
<ol>
- <li>All static imports in a single group
- <ul>
- <li>Static import is not used for static nested classes; these are imported with normal imports
- in the appropriate group below.</li>
- </ul>
- </li>
-
- <li><code>com.google</code> imports
- (only if this source file is in the <code>com.google</code> package
- space)</li>
+ <li>All static imports in a single block.</li>
+ <li>All non-static imports in a single block.</li>
+</ol>
- <li>Third-party imports, one group per top-level package, in ASCII sort order
- <ul>
- <li>for example: <code>android</code>, <code>com</code>, <code>org</code>, <code>sun</code></li>
- </ul>
- </li>
+<p>If there are both static and non-static imports, a single blank line separates the two
+blocks. There are no other blank lines between import statements.</p>
- <li><code>java</code> imports</li>
+<p>Within each block the imported names appear in ASCII sort order. (<strong>Note:</strong>
+this is not the same as the import <em>statements</em> being in ASCII sort order, since '.'
+sorts before ';'.)</p>
- <li><code>javax</code> imports</li>
-</ol>
-<p>Within a group there are no blank lines, and the imported names appear in ASCII sort
-order. (<strong>Note:</strong> this is not the same as the import <em>statements</em> being in
-ASCII sort order; the presence of semicolons warps the result.)</p>
<h3 id="s3.4-class-declaration">3.4 Class declaration</h3>
@@ -284,9 +268,15 @@ <h4 id="s4.1.2-blocks-k-r-style">4.1.2 Nonempty blocks: K &amp; R style</h4>
<code class="prettyprint lang-java">else</code> or a comma.</li>
</ul>
-<p>Example:</p>
+<p>Examples:</p>
+
+<pre class="prettyprint lang-java">return () -&gt; {
+ while (condition()) {
+ method();
+ }
+};
-<pre class="prettyprint lang-java">return new MyClass() {
+return new MyClass() {
@Override public void method() {
if (condition()) {
try {
@@ -381,7 +371,8 @@ <h4 id="s4.5.1-line-wrapping-where-to-break">4.5.1 Where to break</h4>
such as C++ and JavaScript.)
<ul>
<li>This also applies to the following "operator-like" symbols: the dot separator
- (<code class="prettyprint lang-java">.</code>), the ampersand in type bounds
+ (<code class="prettyprint lang-java">.</code>), the two colons of a method reference
+ (<code class="prettyprint lang-java">::</code>), the ampersand in type bounds
(<code class="prettyprint lang-java">&lt;T extends Foo &amp; Bar&gt;</code>), and the pipe in
catch blocks
(<code class="prettyprint lang-java">catch (FooException | BarException e)</code>).</li>
@@ -443,7 +434,8 @@ <h4 id="s4.6.1-vertical-whitespace">4.6.1 Vertical Whitespace</h4>
</li><li><em>Optionally</em> before the first member or after the last member of the class (neither
encouraged nor discouraged).</li>
- <li>As required by other sections of this document (such as Section 3.3,
+ <li>As required by other sections of this document (such as Section 3,
+ <a href="#s3-source-file-structure">Source file structure</a>, and Section 3.3,
<a href="#s3.3-import-statements">Import statements</a>).</li>
</ol>
@@ -488,6 +480,17 @@ <h4 id="s4.6.2-horizontal-whitespace">4.6.2 Horizontal whitespace</h4>
<li>the colon (<code class="prettyprint lang-java">:</code>) in an enhanced
<code class="prettyprint lang-java">for</code> ("foreach") statement</li>
+
+ <li>the arrow in a lambda expression:
+ <code class="prettyprint lang-java">(String str) -&gt; str.length()</code></li>
+ </ul>
+ but not
+
+ <ul>
+ <li>the two colons (<code class="prettyprint lang-java">::</code>) of a method reference, which
+ is written like <code class="prettyprint lang-java">Object::toString</code></li>
+ <li>the dot separator (<code class="prettyprint lang-java">.</code>), which is written like
+ <code class="prettyprint lang-java">object.toString()</code></li>
</ul>
</li>
@@ -690,7 +693,8 @@ <h4 id="s4.8.5-annotations">4.8.5 Annotations</h4>
<pre class="prettyprint lang-java">@Partial @Mock DataLoader loader;
</pre>
-<p>There are no specific rules for formatting parameter and local variable annotations.</p>
+<p>There are no specific rules for formatting annotations on parameters, local variables, or types.
+</p>
<a name="comments"></a>
<h4 id="s4.8.6-comments">4.8.6 Comments</h4>
@@ -729,7 +733,7 @@ <h4 id="s4.8.7-modifiers">4.8.7 Modifiers</h4>
recommended by the Java Language Specification:
</p>
-<pre>public protected private abstract static final transient volatile synchronized native strictfp
+<pre>public protected private abstract default static final transient volatile synchronized native strictfp
</pre>
<h4 id="s4.8.8-numeric-literals">4.8.8 Numeric Literals</h4>

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