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    <p>In most situations, you should use String literals to avoid creating unnecessary objects. This is actually <strong>Item 5: Avoid creating unnecessary objects</strong> of Effective Java:</p> <blockquote> <h3>Item 5: Avoid creating unnecessary objects</h3> <p>It is often appropriate to reuse a single object instead of creating a new functionally equivalent object each time it is needed. Reuse can be both faster and more stylish. An object can always be reused if it is immutable (Item 15). As an extreme example of what not to do, consider this statement:</p> <pre><code>String s = new String("stringette"); // DON'T DO THIS! </code></pre> <p>The statement creates a new <code>String</code> instance each time it is executed, and none of those object creations is necessary. The argument to the String constructor (<code>"stringette"</code>) is itself a String instance, functionally identical to all of the objects created by the constructor. If this usage occurs in a loop or in a frequently invoked method, millions of String instances can be created needlessly. The improved version is simply the following:</p> <pre><code>String s = "stringette"; </code></pre> <p>This version uses a single <code>String</code> instance, rather than creating a new one each time it is executed. Furthermore, it is guaranteed that the object will be reused by any other code running in the same virtual machine that happens to con- tain the same string literal [JLS, 3.10.5]</p> </blockquote> <p>There is however one situation where you want to use the <code>new String(String)</code> constructor: when you want to force a substring to copy to a new underlying character array like in:</p> <pre><code>String tiny = new String(huge.substring(0, 10)); </code></pre> <p>This will allow the big underlying <code>char[]</code> from the original <code>huge</code> String to be recycled by the GC.</p>
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    1. POwhat is the advantage of string object as compared to string literal
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    1. USPascal Thivent
    1. USPascal Thivent
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      1. VTUpMod
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    1. COCould you explain why String `tiny = new String(huge.substring(0, 10));` is eligible for GC? On the other hand why `tiny = huge.substring(0, 10);` not eligible?
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    2. CO@Sujee With `tiny = huge.substring(0, 10)`, `tiny` would use the **same** `char[]` than `huge`. With `String tiny = new String(huge.substring(0, 10))`, `tiny` would use a new (smaller) `char[]`, allowing the big one to be recycled. Check the sources for the details.
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    3. COThank you @Pascal Thivent.
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