What Are Variables?
In Java, a variable is a container for storing data. Each variable has a specific data type that determines what kind of data it can hold. Variables must be declared before they are used.
Declaring Variables
Here’s the syntax to declare a variable in Java:
<span class="line"><span style="color: #81A1C1">public</span><span style="color: #D8DEE9FF"> </span><span style="color: #81A1C1">class</span><span style="color: #D8DEE9FF"> </span><span style="color: #8FBCBB">DataTypesExample</span><span style="color: #D8DEE9FF"> </span><span style="color: #ECEFF4">{</span></span>
<span class="line"><span style="color: #D8DEE9FF"> </span><span style="color: #81A1C1">public</span><span style="color: #D8DEE9FF"> </span><span style="color: #81A1C1">static</span><span style="color: #D8DEE9FF"> void </span><span style="color: #88C0D0">main</span><span style="color: #ECEFF4">(</span><span style="color: #81A1C1">String</span><span style="color: #ECEFF4">[]</span><span style="color: #88C0D0"> args</span><span style="color: #ECEFF4">)</span><span style="color: #D8DEE9FF"> </span><span style="color: #ECEFF4">{</span></span>
<span class="line"><span style="color: #D8DEE9FF"> </span><span style="color: #81A1C1">int</span><span style="color: #D8DEE9FF"> age </span><span style="color: #81A1C1">=</span><span style="color: #D8DEE9FF"> </span><span style="color: #B48EAD">30</span><span style="color: #81A1C1">;</span></span>
<span class="line"><span style="color: #D8DEE9FF"> </span><span style="color: #81A1C1">double</span><span style="color: #D8DEE9FF"> salary </span><span style="color: #81A1C1">=</span><span style="color: #D8DEE9FF"> </span><span style="color: #B48EAD">50000</span><span style="color: #ECEFF4">.</span><span style="color: #B48EAD">75</span><span style="color: #81A1C1">;</span></span>
<span class="line"><span style="color: #D8DEE9FF"> char grade </span><span style="color: #81A1C1">=</span><span style="color: #D8DEE9FF"> </span><span style="color: #ECEFF4">'</span><span style="color: #A3BE8C">A</span><span style="color: #ECEFF4">'</span><span style="color: #81A1C1">;</span></span>
<span class="line"><span style="color: #D8DEE9FF"> </span><span style="color: #81A1C1">boolean</span><span style="color: #D8DEE9FF"> isEmployed </span><span style="color: #81A1C1">=</span><span style="color: #D8DEE9FF"> </span><span style="color: #81A1C1">true;</span></span>
<span class="line"></span>
<span class="line"><span style="color: #D8DEE9FF"> System</span><span style="color: #81A1C1">.</span><span style="color: #D8DEE9FF">out</span><span style="color: #81A1C1">.</span><span style="color: #88C0D0">println</span><span style="color: #ECEFF4">(</span><span style="color: #ECEFF4">"</span><span style="color: #A3BE8C">Age: </span><span style="color: #ECEFF4">"</span><span style="color: #88C0D0"> </span><span style="color: #81A1C1">+</span><span style="color: #88C0D0"> age</span><span style="color: #ECEFF4">)</span><span style="color: #81A1C1">;</span></span>
<span class="line"><span style="color: #D8DEE9FF"> System</span><span style="color: #81A1C1">.</span><span style="color: #D8DEE9FF">out</span><span style="color: #81A1C1">.</span><span style="color: #88C0D0">println</span><span style="color: #ECEFF4">(</span><span style="color: #ECEFF4">"</span><span style="color: #A3BE8C">Salary: </span><span style="color: #ECEFF4">"</span><span style="color: #88C0D0"> </span><span style="color: #81A1C1">+</span><span style="color: #88C0D0"> salary</span><span style="color: #ECEFF4">)</span><span style="color: #81A1C1">;</span></span>
<span class="line"><span style="color: #D8DEE9FF"> System</span><span style="color: #81A1C1">.</span><span style="color: #D8DEE9FF">out</span><span style="color: #81A1C1">.</span><span style="color: #88C0D0">println</span><span style="color: #ECEFF4">(</span><span style="color: #ECEFF4">"</span><span style="color: #A3BE8C">Grade: </span><span style="color: #ECEFF4">"</span><span style="color: #88C0D0"> </span><span style="color: #81A1C1">+</span><span style="color: #88C0D0"> grade</span><span style="color: #ECEFF4">)</span><span style="color: #81A1C1">;</span></span>
<span class="line"><span style="color: #D8DEE9FF"> System</span><span style="color: #81A1C1">.</span><span style="color: #D8DEE9FF">out</span><span style="color: #81A1C1">.</span><span style="color: #88C0D0">println</span><span style="color: #ECEFF4">(</span><span style="color: #ECEFF4">"</span><span style="color: #A3BE8C">Employed: </span><span style="color: #ECEFF4">"</span><span style="color: #88C0D0"> </span><span style="color: #81A1C1">+</span><span style="color: #88C0D0"> isEmployed</span><span style="color: #ECEFF4">)</span><span style="color: #81A1C1">;</span></span>
<span class="line"><span style="color: #D8DEE9FF"> </span><span style="color: #ECEFF4">}</span></span>
<span class="line"><span style="color: #ECEFF4">}</span></span>
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