javac compiling error ( mising package)

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javac 编译java源文件时，提示 package does not exist 的错误

Test.java

import java.security.MessageDigest;

import org.apache.commons.codec.binary.Hex;

public class Test{

    public static void main(String args[]){

        boolean isAlarmed = true;

        boolean aa = isAlarmed || false;

        String queryTimestamp = "1970-01-01T00:00:00+0000";

        System.out.println(queryTimestamp.getBytes());

        try{

            MessageDigest md5 = MessageDigest.getInstance("MD5");

            System.out.println(md5.digest("stringtodigest".getBytes()));

            byte[] value = "stringtodigest".getBytes();

            md5.update(value);

            byte[] digest = md5.digest();

            System.out.println(new String(Hex.encodeHex(digest)));

            System.out.println(md5.digest("stringtodigest".getBytes()));

            System.out.println(md5.digest("stringtodigest".getBytes()));

        }catch(Exception e){ 

        }

    }

}

javac Test.java编译的时候报错！

解决办法：

1. 到mvn repository(http://mvnrepository.com/artifact/commons-codec/commons-codec/1.7)上面吧缺少的 jar 包下载下来，

2. 然后给 CLASSPATH 环境变量在添加一下这个jar 包所在的路径，就可以了。

---------------------------------------------------------------------------------------

参考：https://www.linuxquestions.org/questions/programming-9/javac-compiling-error-mising-package-669775/

javac compiling error ( mising package)

First i have to say I am very new to java. I downloaded java codes from the Internet and try to compile them using javac. I got following error,
Code:

C:\temp\javacrypt>"C:\Program Files\Java\jdk1.6.0_06\bin\javac" RSAExample.java

.\BaseCrypto.java:1: package org.apache.commons.codec does not exist

import org.apache.commons.codec.DecoderException;

                               ^

.\BaseCrypto.java:2: package org.apache.commons.codec.binary does not exist

import org.apache.commons.codec.binary.Hex;

                                      ^

.\BaseCrypto.java:26: cannot find symbol

symbol  : class DecoderException

location: class BaseCrypto

    public static byte[] asByte(String hexString) throws DecoderException {

                                                         ^

.\BaseCrypto.java:16: cannot find symbol

symbol  : variable Hex

location: class BaseCrypto

        return new String(Hex.encodeHex(buf));

                          ^

.\BaseCrypto.java:27: cannot find symbol

symbol  : variable Hex

location: class BaseCrypto

        return Hex.decodeHex(hexString.toCharArray());

               ^

5 errors

I guess i just missed some packages like "org.apache.commons.codec.*",
and that package is not part of standard jdk, right?

How do i get those package? I also have netbean and eclipse, but I haven't tried to use them yet.

-----------------

When you get the package, which is probably a .jar file, add that .jar file to your classpath (environment variable).

EDIT: Specifically, here.

EDIT: I believe on Windows it's something like...

SET CLASSPATH=%CLASSPATH%;C:\path\to\jar\jarfile.jar

----------------------

I downloaded the jar file suggested by elprawn, and it work great!! thank you so much.
I am curious about the suggestion from jay73. Is the package management the software like "yum" or "apt-get", right? What keyword should use to search for it?

----------------------

On a system that uses apt, you can use
aptitude search commons
and you'should get a list of the available commons libraries.On ubuntu:

jurgen@Selena:~$ aptitude search commons

i libcommons-attributes-java - adds C#/.Net-style attributes to Java code

i A libcommons-beanutils-java - utility for manipulating JavaBeans

i libcommons-beanutils-java-doc - Javadoc API for libcommons-beanutils-java

i A libcommons-cli-java - API for working with the command line argu

i A libcommons-codec-java - encoder and decoders such as Base64 and he

i A libcommons-collections-java - A set of abstract data type interfaces and

i A libcommons-collections3-java - A set of abstract data type interfaces and

i libcommons-collections3-java-do - Documentation for libcommons-collections3-

i libcommons-configuration-java - Java based library providing a generic con

p libcommons-csv-java - a Java library for working with csv (comma

p libcommons-csv-java-doc - documentation for libcommons-csv-java

i A libcommons-daemon-java - library to launch Java applications as dae

i A libcommons-dbcp-java - Database Connection Pooling Services

i A libcommons-digester-java - Rule based XML Java object mapping tool

p libcommons-discovery-java - locates classes that implement a given Jav

i A libcommons-el-java - Implementation of the JSP2.0 Expression La

i libcommons-fileupload-java - File upload capability to your servlets an

i libcommons-httpclient-java - A Java(TM) library for creating HTTP clien

i libcommons-httpclient-java-doc - Documentation for libcommons-httpclient-ja

i libcommons-io-java - Common useful IO related classes

i libcommons-io-java-doc - Common useful IO related classes - documen

p libcommons-jexl-java - expression language engine

p libcommons-jxpath-java - manipulate javabean using XPath syntax

p libcommons-jxpath-java-doc - Javadoc API for libcommons-jxpath-java

i A libcommons-lang-java - Extension of the java.lang package

i A libcommons-launcher-java - cross platform java application launcher

i A libcommons-logging-java - commmon wrapper interface for several logg

i A libcommons-modeler-java - convenience library to use Java Management

i libcommons-modeler-java-doc - documentation and examples for Commons Mod

i libcommons-net-java - internet protocol suite Java library

p libcommons-openpgp-java - a common and simple interface for generati

p libcommons-openpgp-java-doc - a common and simple interface for generati

i A libcommons-pool-java - pooling implementation for Java objects

i libcommons-validator-java - ease and speed development and maintenance

p libgettext-commons-java - Java classes for internationalization (i18

p libhibernate-commons-annotation - Hibernate Commons Annotations

p libws-commons-util-java - Common utilities from the Apache Web Servi

p libxml-commons-resolver1.1-java - XML entity and URI resolver library

p libxml-commons-resolver1.1-java - XML entity and URI resolver library -- doc

p libxml-commons-resolver1.1-java - XML entity and URI resolver library -- nat

i libxmlgraphics-commons-java - reusable components used by Batik and FOP