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README.md

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+# Hummingbird
+
+### Java implementation of Uniform Resources (UR)
+
+Hummingbird is a Java implementation of the [Uniform Resources (UR)](https://github.com/BlockchainCommons/Research/blob/master/papers/bcr-2020-005-ur.md) specification.
+It is a direct port of the [URKit](https://github.com/BlockchainCommons/URKit) implementation by Wolf McNally. 
+It contains both the classes to represent a UR, and a UR encoder and decoder to encode and decode to/from the QR representations.
+
+## Configuration
+
+Hummingbird is hosted in Maven Central and can be added as a dependency with the following:
+
+```
+implementation('com.sparrowwallet:hummingbird:1.1')
+```
+
+## Usage
+
+Decoding a UR can be done as follows (here decoding a ``crypto-psbt`` UR type):
+
+```java
+URDecoder decoder = new URDecoder();
+while(decoder.getResult() == null) {
+    //Loop adding QR fragments to the decoder until it has a result
+    String qrText = getFromNextQR();
+    decoder.receivePart(qrText);
+}
+
+URDecoder.Result urResult = decoder.getResult();
+if(urResult.type == ResultType.SUCCESS) {
+    if(urResult.ur.getType().equals(UR.CRYPTO_PSBT_TYPE)) {
+        byte[] psbt = urResult.ur.toBytes();       
+    }
+}
+```
+
+Encoding a UR:
+
+```java
+final int MIN_FRAGMENT_LENGTH = 10;
+final int MAX_FRAGMENT_LENGTH = 100;
+
+UR ur = UR.fromBytes(data);
+UREncoder encoder = new UREncoder(ur, MAX_FRAGMENT_LENGTH, MIN_FRAGMENT_LENGTH, 0);
+while(true) {
+    String fragment = encoder.nextPart();
+    //Show UR fragment as QR code...
+}
+```
+
+## Testing
+
+Hummingbird has a thorough testsuite ported from URKit. The tests can be run with:
+
+```
+./gradlew test
+```
+
+## License
+
+Hummingbird is licensed under the Apache 2 software license.