gnodet commented on code in PR #1296: URL: https://github.com/apache/maven/pull/1296#discussion_r1367067777
########## maven-embedder/src/main/java/org/apache/maven/cli/transfer/FileSizeFormat.java: ########## @@ -0,0 +1,160 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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 org.apache.maven.cli.transfer; + +import java.text.DecimalFormat; +import java.text.DecimalFormatSymbols; +import java.util.Locale; + +/** + * Formats file size with the associated <a href="https://en.wikipedia.org/wiki/Metric_prefix";>SI</a> prefix + * (GB, MB, kB) and using the patterns <code>#0.0</code> for numbers between 1 and 10 + * and <code>###0</code> for numbers between 10 and 1000+ by default. + * + * @see <a href="https://en.wikipedia.org/wiki/Metric_prefix";>https://en.wikipedia.org/wiki/Metric_prefix</a> + * @see <a href="https://en.wikipedia.org/wiki/Binary_prefix";>https://en.wikipedia.org/wiki/Binary_prefix</a> + * @see <a + * href="https://en.wikipedia.org/wiki/Octet_%28computing%29";>https://en.wikipedia.org/wiki/Octet_(computing)</a> + */ +public class FileSizeFormat { + enum ScaleUnit { + BYTE { + @Override + public long bytes() { + return 1L; + } + + @Override + public String symbol() { + return "B"; + } + }, + KILOBYTE { + @Override + public long bytes() { + return 1000L; + } + + @Override + public String symbol() { + return "kB"; + } + }, + MEGABYTE { + @Override + public long bytes() { + return KILOBYTE.bytes() * KILOBYTE.bytes(); + } + + @Override + public String symbol() { + return "MB"; + } + }, + GIGABYTE { + @Override + public long bytes() { + return MEGABYTE.bytes() * KILOBYTE.bytes(); + } + ; + + @Override + public String symbol() { + return "GB"; + } + }; + + public abstract long bytes(); + + public abstract String symbol(); + + public static ScaleUnit getScaleUnit(long size) { + if (size < 0L) { + throw new IllegalArgumentException("file size cannot be negative: " + size); + } + + if (size >= GIGABYTE.bytes()) { + return GIGABYTE; + } else if (size >= MEGABYTE.bytes()) { + return MEGABYTE; + } else if (size >= KILOBYTE.bytes()) { + return KILOBYTE; + } else { + return BYTE; + } + } + } + + private DecimalFormat smallFormat; + private DecimalFormat largeFormat; + + public FileSizeFormat(Locale locale) { + smallFormat = new DecimalFormat("#0.0", new DecimalFormatSymbols(locale)); + largeFormat = new DecimalFormat("###0", new DecimalFormatSymbols(locale)); + } + + public String format(long size) { + return format(size, ScaleUnit.getScaleUnit(size)); + } + + public String getScaleSymbol(long size) { + return ScaleUnit.getScaleUnit(size).symbol(); + } + + @SuppressWarnings("checkstyle:magicnumber") + private String format(long size, ScaleUnit unit) { + if (size < 0L) { + throw new IllegalArgumentException("file size cannot be negative: " + size); + } + + double scaledSize = (double) size / unit.bytes(); + + if (unit == ScaleUnit.BYTE) { + return largeFormat.format(size); Review Comment: The goal is to avoid those calls. `NumberFormat` has methods that take a `StringBuilder`... In `NumberFormat`, I have the following declaration: ``` public final String format(long number) { return format(number, new StringBuffer(), DontCareFieldPosition.INSTANCE).toString(); } ``` so we should go straight to the method that takes a `StringBuffer` to avoid unneeded allocations + toString.... -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@maven.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
