Java Utililty Methods Array Merge

ArrayList<T> ret = new ArrayList();
for (T[] list : many) {
    if (list != null) {
        for (T val : list) {
            if (!ret.contains(val)) {
                ret.add(val);
ret.trimToSize();
return ret;

List<String> sL1 = new ArrayList<String>(Arrays.asList(t1));
for (int i = 0; i < t2.length; i++) {
    if (!sL1.contains(t2[i]))
        sL1.add(t2[i]);
String[] f = sL1.toArray(new String[0]);
return f;

int[] arr = new int[arrA.length + arrB.length];
int a = 0;
int b = 0;
for (int i = 0; i < arr.length; i++) {
    if (a == arrA.length) {
        arr[i] = arrB[b];
        b++;
    } else if (b == arrB.length) {
...

ArrayList<String> merged = new ArrayList<>();
boolean open = false;
StringBuilder builder = new StringBuilder();
for (String arg : args) {
    if (open) {
        if (builder.length() != 0) {
            builder.append(' ');
        if (arg.endsWith("\"")) {
            open = false;
            builder.append(arg.substring(0, arg.length() - 1));
            merged.add(builder.toString());
            builder = new StringBuilder();
        } else {
            builder.append(arg);
    } else if (arg.startsWith("\"")) {
        open = true;
        builder.append(arg.substring(1));
    } else {
        merged.add(arg);
if (builder.length() != 0) {
    merged.add(builder.toString());
return merged.toArray(new String[merged.size()]);

byte[] result = new byte[arr1.length + arr2.length];
for (int i = 0; i < arr1.length; i++)
    result[i] = arr1[i];
for (int i = 0; i < arr2.length; i++)
    result[i + arr1.length] = arr2[i];
return result;

if (arrays == null || arrays.length == 0)
    return;
if (arrays.length == 1) {
    final Object[] array = arrays[0];
    System.arraycopy(array, 0, dest, 0, array.length);
    return;
for (int i = 0, j = arrays.length - 1; i < j; i++) {
...

if (a == null) {
    return b;
if (b == null) {
    return a;
String[] newArray = new String[a.length + b.length];
System.arraycopy(a, 0, newArray, 0, a.length);
...

StringBuilder sb = new StringBuilder();
for (T obj : objs) {
    sb.append(obj).append(concatenator);
return objs.length == 0 ? "" : sb.substring(0, sb.length() - concatenator.length());

if (array == null) {
    return null;
if (middleDelimiter == null) {
    middleDelimiter = "";
if (lastDelimiter == null) {
    lastDelimiter = middleDelimiter;
...

Object[] bufret = null;
int len1 = 0;
int len2 = 0;
if (buf1 != null)
    len1 = buf1.length;
if (buf2 != null)
    len2 = buf2.length;
if (len1 + len2 > 0)
...