`scanByte` throws `NumberFormatException` for URIs that start with numbers, e.g., https://11111111.x.y/ The current flow is `parseIPv4Address` → `scanIPv4Address` → `scanByte`. `parseIPv4Address` uses `NumberFormatException` for control flow, so it captures the exception, ignores it, and returns -1. This has been reported by AWS customer to cause low performance. Details: [JDK-8353013](https://bugs.openjdk.org/browse/JDK-8353013) & https://github.com/aws/aws-sdk-java-v2/issues/5933
This PR avoids NumberFormatException by skipping calls to `Integer.parseInt` if the number of digits in the octet is > 3. I benchmarked on local machine for potential regressions. https://gist.github.com/rk-kmr/cb1a3d59225c17b180a29cc125ebf887 Benchmark Mode Cnt Score Error Units URIBenchMark.newImplWithNormalUrl thrpt 10 0.004 ± 0.001 ops/ns URIBenchMark.newImplWithNumberlUrl thrpt 10 0.004 ± 0.001 ops/ns URIBenchMark.oldImplWithNormalUrl thrpt 10 0.004 ± 0.001 ops/ns URIBenchMark.oldImplWithNumUrl thrpt 10 0.001 ± 0.001 ops/ns URIBenchMark.newImplWithNormalUrl avgt 10 236.762 ± 8.700 ns/op URIBenchMark.newImplWithNumberlUrl avgt 10 264.017 ± 7.274 ns/op URIBenchMark.oldImplWithNormalUrl avgt 10 233.853 ± 6.539 ns/op URIBenchMark.oldImplWithNumUrl avgt 10 1183.572 ± 29.242 ns/op I ran following tests. make test-tier1 make test-tier2 make test TEST=jdk/java/net ------------- Commit messages: - Update src/java.base/share/classes/java/net/URI.java - make test pass - add unit test - Address PR comments - Merge branch 'openjdk:master' into JDK-8353013 - reuse scan method instead - avoid parseInt if scanned digit count > 3 Changes: https://git.openjdk.org/jdk/pull/24295/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24295&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8353013 Stats: 40 lines in 2 files changed: 37 ins; 0 del; 3 mod Patch: https://git.openjdk.org/jdk/pull/24295.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/24295/head:pull/24295 PR: https://git.openjdk.org/jdk/pull/24295
