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Remove home-grown binary search function in PDF417Common

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This commit is contained in:
Sean Owen 2014-05-22 09:21:55 +01:00
parent c7dfb89a16
commit 6b9a59a593
1 changed files with 4 additions and 27 deletions
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31
core/src/main/java/com/google/zxing/pdf417/PDF417Common.java
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@ -15,6 +15,7 @@
*/
package com.google.zxing.pdf417;
import java.util.Arrays;
import java.util.Collection;
/**
@ -63,38 +64,14 @@ public final class PDF417Common {
* @param symbol encoded symbol to translate to a codeword
* @return the codeword corresponding to the symbol.
*/
public static int getCodeword(long symbol) {
long sym = symbol & 0x3FFFF;
int i = findCodewordIndex(sym);
if (i == -1) {
public static int getCodeword(int symbol) {
int i = Arrays.binarySearch(SYMBOL_TABLE, symbol & 0x3FFFF);
if (i < 0) {
return -1;
}
return (CODEWORD_TABLE[i] - 1) % NUMBER_OF_CODEWORDS;
}
/**
* Use a binary search to find the index of the codeword corresponding to
* this symbol.
*
* @param symbol the symbol from the barcode.
* @return the index into the codeword table.
*/
private static int findCodewordIndex(long symbol) {
int first = 0;
int upto = SYMBOL_TABLE.length;
while (first < upto) {
int mid = (first + upto) / 2; // Compute mid point.
if (symbol < SYMBOL_TABLE[mid]) {
upto = mid; // continue search in bottom half.
} else if (symbol > SYMBOL_TABLE[mid]) {
first = mid + 1; // continue search in top half.
} else {
return mid; // Found it. return position
}
}
return -1;
}
/**
* The sorted table of all possible symbols. Extracted from the PDF417
* specification. The index of a symbol in this table corresponds to the