Java Utililty Methods Binary Search

int binarySearch(byte[] a, byte key, int startPos)
binary Search

if (startPos > a.length || startPos < 0) {
 return -1;
for (int i = startPos; i < a.length; i++) {
 if (a[i] == key) {
 return i;
return -1;

int binarySearch(byte[] a, int key)
Search for a big-endian 4-byte integer in a array of bytes.

int low = 0;
int high = a.length;
while (low < high) {
 int mid = (low + high) >>> 1;
 if (mid % 4 != 0) {
 if (high == a.length) {
 mid = low;
 } else {
...

int binarySearch(byte[] readBuffer, int offset, int length, byte value)
binary Search

for (int i = offset; i < length; i++) {
 if (readBuffer[i] == value)
 return i;
return -1;

int binarySearch(char[] arr, int key)
binary Search

int length = arr.length;
if (key <= arr[length - 1]) {
 int l = 0;
 int r = length - 1;
 while (l <= r) {
 int mid = (l + r) >>> 1;
 char val = arr[mid];
 if (key > val) {
...

int binarySearch(double experience, int min, int max)
Utilizes a basic binary search algorithm to find the level for the specified experience.

int mid = (min + max) / 2;
double value = EXPERIENCE_TABLE[mid];
if (value > experience) {
 return binarySearch(experience, min, mid - 1);
} else if (value == experience || EXPERIENCE_TABLE[mid + 1] > experience) {
 return mid + 1;
} else {
 return binarySearch(experience, mid + 1, max);
...

int binarySearch(double values[], double search)
binary Search

int min = 0, max = values.length;
int index = max / 2;
while (max - min > 1) {
 if (values[index] == search) {
 return index;
 if (values[index] < search) {
 min = index;
...

int binarySearch(double[] a, double key)
Perform a binary search on a sorted array a to find the element with the nearest element to key .

int l = 0;
int h = a.length - 1;
int i;
do {
 i = (int) (((long) l + (long) h) / 2L);
 if (key > a[i]) {
 l = i + 1;
 } else if (key < a[i]) {
...

int binarySearch(double[] arr, double value, int p, int q)
Add by Chuan binary search

if (p > q)
 return p - 1;
int r = (p + q) / 2;
if (arr[r] == value)
 return r;
else if (arr[r] < value)
 return binarySearch(arr, value, r + 1, q);
else
...

int binarySearch(final double[] array, final double val)
binary Search

int low = 0;
int high = array.length - 1;
final boolean keyIsNaN = Double.isNaN(val);
while (low <= high) {
 final int mid = (low + high) >> 1;
 final double midVal = array[mid];
 if (midVal < val) { 
 low = mid + 1;
...

int binarySearch(final Enum[] full, final int[] partial, final char key, final int index)
binary Search

int low = 0;
int high = partial.length - 1;
while (low <= high) {
 int mid = (low + high) >>> 1;
 final String name = full[partial[mid]].toString();
 char midVal = index < name.length() ? name.charAt(index) : ' ';
 if (midVal < key)
 low = mid + 1;
...