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copied!<p><code>new String("text");</code> explicitly creates a new and referentially distinct instance of a <code>String</code> object; <code>String s = "text";</code> may reuse an instance from the <strong>string constant pool</strong> if one is available.</p> <p>You <em>very rarely</em> would ever want to use the <code>new String(anotherString)</code> constructor. From the API:</p> <blockquote> <p><a href="http://java.sun.com/javase/6/docs/api/java/lang/String.html#String%28java.lang.String%29" rel="noreferrer"><code>String(String original)</code></a> : Initializes a <em>newly created</em> <code>String</code> object so that it represents the same sequence of characters as the argument; in other words, the newly created string is a copy of the argument string. Unless an explicit copy of original is needed, use of this constructor is unnecessary since strings are immutable. </p> </blockquote> <h3>Related questions</h3> <ul> <li><a href="https://stackoverflow.com/questions/334518/java-strings-string-s-new-stringsilly"> Java Strings: “String s = new String(”silly“);” </a></li> <li><a href="https://stackoverflow.com/questions/2009228/strings-are-objects-in-java-so-why-dont-we-use-new-to-create-them"> Strings are objects in Java, so why don’t we use ‘new’ to create them? </a></li> </ul> <hr> <h3>What referential distinction means</h3> <p>Examine the following snippet:</p> <pre><code> String s1 = "foobar"; String s2 = "foobar"; System.out.println(s1 == s2); // true s2 = new String("foobar"); System.out.println(s1 == s2); // false System.out.println(s1.equals(s2)); // true </code></pre> <p><code>==</code> on two reference types is a reference identity comparison. Two objects that are <code>equals</code> are not necessarily <code>==</code>. It is usually wrong to use <code>==</code> on reference types; most of the time <code>equals</code> need to be used instead.</p> <p>Nonetheless, if for whatever reason you need to create two <code>equals</code> but not <code>==</code> string, you <em>can</em> use the <code>new String(anotherString)</code> constructor. It needs to be said again, however, that this is <em>very</em> peculiar, and is rarely the intention.</p> <h3>References</h3> <ul> <li><a href="http://java.sun.com/docs/books/jls/third_edition/html/expressions.html#15.21.3" rel="noreferrer">JLS 15.21.3 Reference Equality Operators == and !=</a></li> <li><a href="http://java.sun.com/javase/6/docs/api/java/lang/Object.html#equals%28java.lang.Object%29" rel="noreferrer"><code>class Object</code> - <code>boolean Object(equals)</code></a></li> </ul> <h3>Related issues</h3> <ul> <li><a href="https://stackoverflow.com/questions/767372/java-string-equals-versus"> Java String.equals versus == </a></li> <li><a href="https://stackoverflow.com/questions/513832/how-do-i-compare-strings-in-java">How do I compare strings in Java?</a></li> </ul>

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