open-keychain/libraries/zxing/src/com/google/zxing/qrcode/decoder/ErrorCorrectionLevel.java
2014-01-06 22:52:45 +01:00

87 lines
2.2 KiB
Java

/*
* Copyright 2007 ZXing authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.zxing.qrcode.decoder;
/**
* <p>See ISO 18004:2006, 6.5.1. This enum encapsulates the four error correction levels
* defined by the QR code standard.</p>
*
* @author Sean Owen
*/
public final class ErrorCorrectionLevel {
// No, we can't use an enum here. J2ME doesn't support it.
/**
* L = ~7% correction
*/
public static final ErrorCorrectionLevel L = new ErrorCorrectionLevel(0, 0x01, "L");
/**
* M = ~15% correction
*/
public static final ErrorCorrectionLevel M = new ErrorCorrectionLevel(1, 0x00, "M");
/**
* Q = ~25% correction
*/
public static final ErrorCorrectionLevel Q = new ErrorCorrectionLevel(2, 0x03, "Q");
/**
* H = ~30% correction
*/
public static final ErrorCorrectionLevel H = new ErrorCorrectionLevel(3, 0x02, "H");
private static final ErrorCorrectionLevel[] FOR_BITS = {M, L, H, Q};
private final int ordinal;
private final int bits;
private final String name;
private ErrorCorrectionLevel(int ordinal, int bits, String name) {
this.ordinal = ordinal;
this.bits = bits;
this.name = name;
}
public int ordinal() {
return ordinal;
}
public int getBits() {
return bits;
}
public String getName() {
return name;
}
public String toString() {
return name;
}
/**
* @param bits int containing the two bits encoding a QR Code's error correction level
* @return ErrorCorrectionLevel representing the encoded error correction level
*/
public static ErrorCorrectionLevel forBits(int bits) {
if (bits < 0 || bits >= FOR_BITS.length) {
throw new IllegalArgumentException();
}
return FOR_BITS[bits];
}
}