Como posso ler um arquivo de recursos de um arquivo jar java?

Eu gostaria de salientar que um dos problemas é, o que acontece se os mesmos recursos são Eles encontram em vários arquivos jar. Deixe-nos querer ler /org/node/foo.txt mas não de um arquivo, mas de cada um dos arquivos jars.
Eu acabei com esse mesmo problema. vezes antes. Eu estava esperando no JDK 7 que alguém escreveu uma rota de classe do sistema de arquivos, mas, infelizmente, ainda não.
Spring tem a classe de recursos que lhe permite carregar a classe de recursos muito bem.
I escreveu um pequeno protótipo para resolver este grande problema de ler recursos na forma de vários arquivos JAR. O protótipo não lida com cada caso extremo, mas ele lida com a busca de recursos nos diretórios que estão nos arquivos jar.
Eu usei o estouro de pilha por algum tempo. Esta é a segunda resposta que me lembro de responder a uma pergunta, então me perdoo se eu for muito tempo (é minha natureza).
Este é um protótipo dos recursos do leitor. O protótipo é desprovido de um sistema robusto de verificação de erros.
Eu tenho dois protótipos frascos que eu tenho o programa de instalação.

 <pre> <dependency> <groupId>invoke</groupId> <artifactId>invoke</artifactId> <version>1.0-SNAPSHOT</version> </dependency> <dependency> <groupId>node</groupId> <artifactId>node</artifactId> <version>1.0-SNAPSHOT</version> </dependency>

arquivos Jar cada tem um Arquivo em / org / nó / chamado Resource.txt.
Este é apenas um protótipo do que um controlador olharia com Classpath: // Eu também tenho um recurso.foo.txt em meus recursos locais para este projeto.
Recolha todos eles e imprima-os.

  package com.foo; import java.io.File; import java.io.FileReader; import java.io.InputStreamReader; import java.io.Reader; import java.net.URI; import java.net.URL; import java.util.Enumeration; import java.util.zip.ZipEntry; import java.util.zip.ZipFile; /** * Prototype resource reader. * This prototype is devoid of error checking. * * * I have two prototype jar files that I have setup. * <pre> * <dependency> * <groupId>invoke</groupId> * <artifactId>invoke</artifactId> * <version>1.0-SNAPSHOT</version> * </dependency> * * <dependency> * <groupId>node</groupId> * <artifactId>node</artifactId> * <version>1.0-SNAPSHOT</version> * </dependency> * </pre> * The jar files each have a file under /org/node/ called resource.txt. * <br /> * This is just a prototype of what a handler would look like with classpath:// * I also have a resource.foo.txt in my local resources for this project. * <br /> */ public class ClasspathReader { public static void main(String args) throws Exception { /* This project includes two jar files that each have a resource located in /org/node/ called resource.txt. */ /* Name space is just a device I am using to see if a file in a dir starts with a name space. Think of namespace like a file extension but it is the start of the file not the end. */ String namespace = "resource"; //someResource is classpath. String someResource = args.length > 0 ? args : //"classpath:///org/node/resource.txt"; It works with files "classpath:///org/node/"; //It also works with directories URI someResourceURI = URI.create(someResource); System.out.println("URI of resource = " + someResourceURI); someResource = someResourceURI.getPath(); System.out.println("PATH of resource =" + someResource); boolean isDir = !someResource.endsWith(".txt"); /** Classpath resource can never really start with a starting slash. * Logically they do, but in reality you have to strip it. * This is a known behavior of classpath resources. * It works with a slash unless the resource is in a jar file. * Bottom line, by stripping it, it always works. */ if (someResource.startsWith("/")) { someResource = someResource.substring(1); } /* Use the ClassLoader to lookup all resources that have this name. Look for all resources that match the location we are looking for. */ Enumeration resources = null; /* Check the context classloader first. Always use this if available. */ try { resources = Thread.currentThread().getContextClassLoader().getResources(someResource); } catch (Exception ex) { ex.printStackTrace(); } if (resources == null || !resources.hasMoreElements()) { resources = ClasspathReader.class.getClassLoader().getResources(someResource); } //Now iterate over the URLs of the resources from the classpath while (resources.hasMoreElements()) { URL resource = resources.nextElement(); /* if the resource is a file, it just means that we can use normal mechanism to scan the directory. */ if (resource.getProtocol().equals("file")) { //if it is a file then we can handle it the normal way. handleFile(resource, namespace); continue; } System.out.println("Resource " + resource); /* Split up the string that looks like this: jar:file:/Users/rick/.m2/repository/invoke/invoke/1.0-SNAPSHOT/invoke-1.0-SNAPSHOT.jar!/org/node/ into this /Users/rick/.m2/repository/invoke/invoke/1.0-SNAPSHOT/invoke-1.0-SNAPSHOT.jar and this /org/node/ */ String split = resource.toString().split(":"); String split2 = split.split("!"); String zipFileName = split2; String sresource = split2; System.out.printf("After split zip file name = %s," + " \nresource in zip %s \n", zipFileName, sresource); /* Open up the zip file. */ ZipFile zipFile = new ZipFile(zipFileName); /* Iterate through the entries. */ Enumeration entries = zipFile.entries(); while (entries.hasMoreElements()) { ZipEntry entry = entries.nextElement(); /* If it is a directory, then skip it. */ if (entry.isDirectory()) { continue; } String entryName = entry.getName(); System.out.printf("zip entry name %s \n", entryName); /* If it does not start with our someResource String then it is not our resource so continue. */ if (!entryName.startsWith(someResource)) { continue; } /* the fileName part from the entry name. * where /foo/bar/foo/bee/bar.txt, bar.txt is the file */ String fileName = entryName.substring(entryName.lastIndexOf("/") + 1); System.out.printf("fileName %s \n", fileName); /* See if the file starts with our namespace and ends with our extension. */ if (fileName.startsWith(namespace) && fileName.endsWith(".txt")) { /* If you found the file, print out the contents fo the file to System.out.*/ try (Reader reader = new InputStreamReader(zipFile.getInputStream(entry))) { StringBuilder builder = new StringBuilder(); int ch = 0; while ((ch = reader.read()) != -1) { builder.append((char) ch); } System.out.printf("zip fileName = %s\n\n####\n contents of file %s\n###\n", entryName, builder); } catch (Exception ex) { ex.printStackTrace(); } } //use the entry to see if it's the file '1.txt' //Read from the byte using file.getInputStream(entry) } } } /** * The file was on the file system not a zip file, * this is here for completeness for this example. * otherwise. * * @param resource * @param namespace * @throws Exception */ private static void handleFile(URL resource, String namespace) throws Exception { System.out.println("Handle this resource as a file " + resource); URI uri = resource.toURI(); File file = new File(uri.getPath()); if (file.isDirectory()) { for (File childFile : file.listFiles()) { if (childFile.isDirectory()) { continue; } String fileName = childFile.getName(); if (fileName.startsWith(namespace) && fileName.endsWith("txt")) { try (FileReader reader = new FileReader(childFile)) { StringBuilder builder = new StringBuilder(); int ch = 0; while ((ch = reader.read()) != -1) { builder.append((char) ch); } System.out.printf("fileName = %s\n\n####\n contents of file %s\n###\n", childFile, builder); } catch (Exception ex) { ex.printStackTrace(); } } } } else { String fileName = file.getName(); if (fileName.startsWith(namespace) && fileName.endsWith("txt")) { try (FileReader reader = new FileReader(file)) { StringBuilder builder = new StringBuilder(); int ch = 0; while ((ch = reader.read()) != -1) { builder.append((char) ch); } System.out.printf("fileName = %s\n\n####\n contents of file %s\n###\n", fileName, builder); } catch (Exception ex) { ex.printStackTrace(); } } } } } 

Você pode ver um exemplo mais completo aqui com a saída de exemplo.

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