A “for” loop to iterate over an enumeration in Java | Java Debug notes

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How do I configure ports for Spring Boot applications

I enum basic and intermediate directions in Java:

public enum Direction {
   NORTH,
   NORTHEAST,
   EAST,
   SOUTHEAST,
   SOUTH,
   SOUTHWEST,
   WEST,
   NORTHWEST
}
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How do I write a for loop that accesses these enum valuesCopy the code

Answer:

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.values()

You can call this method on an enumeration with values().

for (Direction dir : Direction.values()) {
  // do what you want
}
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The values() method is implicitly declared by the compiler. Therefore, it is not listed in the Enum documentation.

Answer:

We can get all constants of the enumerated type by calling the implicit method of public static T[] values() :

 for (Direction d : Direction.values()) {
     System.out.println(d);
 }

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The article translated from am2dgbqfb6mk75jcyanzabc67y ac4c6men2g7xr2a – stackoverflow – com. Translate. Goog/questions / 1…

The authors suggest: Refer to my previous answer to the nested enumeration template:How do I get enumeration values from string values in Java?

private static class IntegerCache { static final int low = -128; static final int high; static final Integer cache[]; static { // high value may be configured by property int h = 127; String integerCacheHighPropValue = sun.misc.VM.getSavedProperty("java.lang.Integer.IntegerCache.high"); if (integerCacheHighPropValue ! = null) { try { int i = parseInt(integerCacheHighPropValue); i = Math.max(i, 127); // Maximum array size is Integer.MAX_VALUE h = Math.min(i, Integer.MAX_VALUE - (-low) -1); } catch( NumberFormatException nfe) { // If the property cannot be parsed into an int, ignore it. } } high = h; cache = new Integer[(high - low) + 1]; int j = low; for(int k = 0; k < cache.length; k++) cache[k] = new Integer(j++); // range [-128, 127] must be interned (JLS7 5.1.7) Assert IntegerCache. High >= 127; } private IntegerCache() {} }Copy the code

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