java中使用protobuf总结

基本没怎么接触过java编程，别的团队发过来一个用java编写的存储pb的文件，让拆分和解析，硬着头皮做一下，在此将步骤做个记录：

下载安装protobuf

https://github.com/protocolbuffers/protobuf/tags?after=v3.6.1.2

编译protoc解释器

tar -zxvf protobuf-all-3.6.1.tar.gz 
cd protobuf-3.6.1/
sudo ./autogen.sh
sudo ./configure
sudo make
sudo make check
sudo make install
sudo ldconfig

定义接口

syntax = "proto3";
package com.union.fun;message Metric {string name = 1;string type = 2;float value = 3;repeated string tags = 4;}

生成java语言的接口文件

protoc -I=/home/tiger/java_protobuf --java_out=/tiger/java_protobuf metric.proto

安装jdk8

sudo apt-get update

sudo apt-get install openjdk-8-jdk

安装maven

wget http://mirror.bit.edu.cn/apache/maven/maven-3/3.5.2/binaries/apache-maven-3.5.2-bin.tar.gz
tar -zvxf apache-maven-3.5.2-bin.tar.gz
复制到/opt/目录
cp apache-maven-3.5.2-bin.tar.gz /opt
设置环境变量
打开/etc/profile，配置PATH变量
sudo vim /etc/profile
export  MAVEN_HOME=/opt/apache-maven-3.5.2
export PATH=$MAVEN_HOME/bin:$PATH

生成protobuf对应jar包

cd protobuf-3.6.1/java

测试maven

mvn test

打包生成jar文件

mvn package

protobuf-java-3.6.1.jar文件在 core/target目录

protobuf-java-util-3.6.1.jar文件在 util/target目录

生成java接口

protoc -I=/home/tiger/java_protobuf --java_out=/tiger/java_protobuf metric.proto

代码编写

HelloWorld.java

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.FileNotFoundException;
import java.nio.ByteBuffer;
import java.io.FileOutputStream;
import java.io.PrintWriter;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.io.FileWriter;
import java.io.Writer;import com.union.fun.MetricOuterClass;public class HelloWorld {private static String currentPath = "";private static String strFileName = "testData.log";private static String strFileNameCatalog = "testData_Catalog.txt";private static File outputFile = null;private static FileOutputStream fileOutputStream = null;private static File outputCatalogFile = null;private static PrintWriter outputCatalogFileWriter = null;private static void savetestDataCatalog(String catalog) {try {if (!outputCatalogFile.getParentFile().exists()) {outputCatalogFile.getParentFile().mkdirs();System.out.println("savetestDataCatalog 1");}if (!outputCatalogFile.exists()) {outputCatalogFile.createNewFile();System.out.println("savetestDataCatalog 2");}if (outputCatalogFileWriter == null) {outputCatalogFileWriter = new PrintWriter(outputCatalogFile);System.out.println("savetestDataCatalog 3");}outputCatalogFileWriter.print(catalog);//System.out.println(catalog);} catch (Exception e) {e.printStackTrace();}}private static void savetestData(MetricOuterClass.Metric testData) {try {if (!outputFile.getParentFile().exists()) {outputFile.getParentFile().mkdirs();System.out.println("savetestData 1");}if (!outputFile.exists()) {outputFile.createNewFile();System.out.println("savetestData 2");}if (fileOutputStream == null) {fileOutputStream = new FileOutputStream(outputFile, true);System.out.println("savetestData 3");}testData.writeDelimitedTo(fileOutputStream);} catch (Exception e) {e.printStackTrace();}}private static void showUseMethod() {System.out.println("check totoal pb frame use param: {-i} {file}");System.out.println("cut pb use param: {-c} {file} {startpos} {endpos}");}private static void showPbTotalFrame(String inputFile) {File file = null;if (file == null) {file = new File(inputFile);}if (!file.exists()) {System.out.println(inputFile + " not exists !");return;}if (outputCatalogFile.exists()) {outputCatalogFile.delete();}if (!outputCatalogFile.getParentFile().exists()) {outputCatalogFile.getParentFile().mkdirs();}try {if (!outputCatalogFile.exists()) {outputCatalogFile.createNewFile();}} catch (IOException e) {e.printStackTrace();return;}try {outputCatalogFileWriter = new PrintWriter(outputCatalogFile);} catch (FileNotFoundException ex) {ex.printStackTrace();return;}int iNormal = 0;try (FileInputStream fileInputStream = new FileInputStream(file)) {while (fileInputStream.available() != 0) {MetricOuterClass.Metric mWorldPackage =MetricOuterClass.Metric.parseDelimitedFrom(fileInputStream);//iTotal++;if (mWorldPackage == null) {//System.out.println("mWorldPackage == null");continue;}//System.out.println("strTimeStamp = " + strTimeStamp);//System.out.println("strSub = " + strSub);/*String currentTime = new SimpleDateFormat("yyyy-MM-dd HH-mm-ss").format(millTimeStamp);if (!strSub.isEmpty()) {currentTime += ".";currentTime += strSub;}iNormal++;  String strItem = String.format("%d %s %s\r\n", iNormal, strTimeStamp, currentTime);*///System.out.println(currentTime);iNormal++; int size = mWorldPackage.getSerializedSize(); String strItem = String.format("%d %d\r\n", iNormal, size);savetestDataCatalog(strItem); }} catch (IOException e) {System.out.println("IOException:" + e);e.printStackTrace();} finally {}outputCatalogFileWriter.close();System.out.println(String.format("total frame: %d", iNormal));}private static void cutPbFrame(String inputFile, int fromPos, int toPos) {File file = null;if (file == null) {file = new File(inputFile);}if (!file.exists()) {System.out.println(inputFile + " not exists !");return;}if (outputFile.exists()) {outputFile.delete();}int iPos = 0;try (FileInputStream fileInputStream = new FileInputStream(file)) {while (fileInputStream.available() != 0) {MetricOuterClass.Metric mWorldPackage =MetricOuterClass.Metric.parseDelimitedFrom(fileInputStream);if (mWorldPackage == null) {System.out.println("mWorldPackage == null");continue;}iPos++;//notifyVehicleDataChanged(mWorldPackage);//SystemClock.sleep(SLEEP_TIME);//int size = mWorldPackage.getSerializedSize();//ByteBuffer byteBuffer = ByteBuffer.allocateDirect(size);//System.out.println(size);if (iPos >= fromPos && iPos <= toPos) {savetestData(mWorldPackage);}}} catch (IOException e) {System.out.println("IOException:" + e);e.printStackTrace();} finally {}}public static void main(String[] args) {System.out.println("======  Welcome to using anp2 pb cutting tool ==========");//System.out.println(args.length);//System.out.println(args);/*System.out.println(System.getProperty("user.dir"));HelloWorld user = new HelloWorld();System.out.println(user.getClass().getResource("").getPath());System.out.println(user.getClass().getResource("/").getPath());System.out.println(user.getClass().getResource("./").getPath());*/if (args.length < 2) {showUseMethod();return;}String inputFile = args[1];String filePriPath = "";String outputDataFile = "";String outputDataCatalogFile = "";String[] split = inputFile.split("\\\\");if (split.length > 1) {System.out.println("windows platfoem");String fileName = split[split.length - 1];filePriPath = inputFile.replace(fileName, "");//System.out.println(fileName);//System.out.println(filePriPath);currentPath = System.getProperty("user.dir") + "\\";outputDataFile = currentPath + "output\\" + strFileName;outputFile = new File(outputDataFile);outputDataCatalogFile = currentPath + "output\\" + strFileNameCatalog;outputCatalogFile = new File(outputDataCatalogFile);            try {outputCatalogFileWriter = new PrintWriter(outputCatalogFile);} catch (FileNotFoundException ex) {ex.printStackTrace();return;}}else {System.out.println("linux platfoem");split = inputFile.split("/");String fileName = split[split.length - 1];filePriPath = inputFile.replace(fileName, "");//System.out.println(fileName);//System.out.println(filePriPath);currentPath = System.getProperty("user.dir") + "/";outputDataFile = currentPath + "output/" + strFileName;outputFile = new File(outputDataFile);outputDataCatalogFile = currentPath + "output/" + strFileNameCatalog;outputCatalogFile = new File(outputDataCatalogFile);}System.out.println("user.dir is: " + currentPath);if (args[0].equals("-i")) {System.out.println("you input file is: " + inputFile);System.out.println("output file is: " + outputDataCatalogFile);showPbTotalFrame(inputFile);return;} else {if (args.length < 4) {showUseMethod();return;}}System.out.println("output file is: " + outputDataFile);int startPos = Integer.parseInt(args[2]);int endPos = Integer.parseInt(args[3]);System.out.println(String.format("you input file is: %s, start pos is: %d, end pos is: %d", inputFile, startPos, endPos));cutPbFrame(inputFile, startPos, endPos);}
}