Inspired by[30 seconds of code](https://github.com/Chalarangelo/30-seconds-of-code), this is a collection of reusable Java code snippets.

Update the sample application with the snippet and add a test for it. After proving that it works update this README.md.

*[Generic two array concatenation](#generic-two-array-concatenation)

publicstatic<T>T[] arrayConcat(T[] first,T[] second) {

T[] result=Arrays.copyOf(first, first.length+ second.length);

System.arraycopy(second,0, result, first.length, second.length);

return result;

}

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importjava.util.Arrays;

publicclassLibrary {

publicbooleansomeLibraryMethod() {

returntrue;

publicstatic <T>T[]arrayConcat(T[]first,T[]second) {

T[]result =Arrays.copyOf(first,first.length +second.length);

System.arraycopy(second,0,result,first.length,second.length);

returnresult;

}

}

importstaticorg.junit.Assert.*;

publicclassLibraryTest {

@TestpublicvoidtestSomeLibraryMethod() {

LibraryclassUnderTest =newLibrary();

assertTrue("someLibraryMethod should return 'true'",classUnderTest.someLibraryMethod());

publicvoidtestArrayConcat() {

Integer[]integers =Library.arrayConcat(newInteger[5],newInteger[5]);

assertEquals(integers.length,10);

String[]strings =Library.arrayConcat(newString[0],newString[0]);

assertEquals(strings.length,0);

try {

Double[]doubles =Library.arrayConcat(null,null);

fail();

}catch (NullPointerExceptione) {

}

}

}