参照官方文档http://nlp.solutions.asia/?p=180

中间碰到的问题，解决方法参考

http://blog.javachen.com/2014/05/20/nutch-intro/

问题1：

compile-core:

[javac] Compiling 180 source files to /root/nutch/build/classes

[javac] error: error reading /usr/lib/jvm/jdk1.8.0_20/jre/lib/ext/._zipfs.jar; error in opening zip file

[javac] error: error reading /usr/lib/jvm/jdk1.8.0_20/jre/lib/ext/._sunec.jar; error in opening zip file

[javac] error: error reading /usr/lib/jvm/jdk1.8.0_20/jre/lib/ext/._sunjce_provider.jar; error in opening zip file

[javac] error: error reading /usr/lib/jvm/jdk1.8.0_20/jre/lib/ext/._sunpkcs11.jar; error in opening zip file

[javac] error: error reading /usr/lib/jvm/jdk1.8.0_20/jre/lib/ext/._jfxrt.jar; error in opening zip file

[javac] error: error reading /usr/lib/jvm/jdk1.8.0_20/jre/lib/ext/._dnsns.jar; error in opening zip file

[javac] error: error reading /usr/lib/jvm/jdk1.8.0_20/jre/lib/ext/._nashorn.jar; error in opening zip file

[javac] error: error reading /usr/lib/jvm/jdk1.8.0_20/jre/lib/ext/._localedata.jar; error in opening zip file

[javac] error: error reading /usr/lib/jvm/jdk1.8.0_20/jre/lib/ext/._cldrdata.jar; error in opening zip file

[javac] warning: [options] bootstrap class path not set in conjunction with -source 1.6

[javac] 9 errors

[javac] 1 warning

BUILD FAILED

/root/nutch/build.xml:101: Compile failed; see the compiler error output for details.

原ext文件夹没有._这些jar，但是有同名zipfs,直接copy,编译通过;

问题2：

root@iZ280izbfjqZ:~/nutch/runtime/local# bin/nutch crawl urls -depth 3 -topN 5

Exception in thread "main" java.lang.ClassNotFoundException: org.apache.gora.sql.store.SqlStore

at java.net.URLClassLoader$1.run(URLClassLoader.java:372)

at java.net.URLClassLoader$1.run(URLClassLoader.java:361)

at java.security.AccessController.doPrivileged(Native Method)

at java.net.URLClassLoader.findClass(URLClassLoader.java:360)

at java.lang.ClassLoader.loadClass(ClassLoader.java:424)

at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)

at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

at java.lang.Class.forName0(Native Method)

at java.lang.Class.forName(Class.java:259)

at org.apache.nutch.storage.StorageUtils.getDataStoreClass(StorageUtils.java:90)

at org.apache.nutch.storage.StorageUtils.createWebStore(StorageUtils.java:74)

at org.apache.nutch.crawl.InjectorJob.run(InjectorJob.java:221)

at org.apache.nutch.crawl.Crawler.runTool(Crawler.java:68)

at org.apache.nutch.crawl.Crawler.run(Crawler.java:136)

at org.apache.nutch.crawl.Crawler.run(Crawler.java:250)

at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65)

at org.apache.nutch.crawl.Crawler.main(Crawler.java:257)

参考以下文章：

http://blog.sina.com.cn/s/blog_3c9872d00101p4f0.html

问题三：

root@iZ280izbfjqZ:~/nutch/runtime/local# bin/nutch crawl urls -depth 3 -topN 5

InjectorJob: Using class org.apache.gora.sql.store.SqlStore as the Gora storage class.

InjectorJob: total number of urls rejected by filters: 0

InjectorJob: total number of urls injected after normalization and filtering: 1

Exception in thread "main" java.lang.RuntimeException: job failed: name=generate: *, jobid=job_local1888916405_0002

at org.apache.nutch.util.NutchJob.waitForCompletion(NutchJob.java:55)

at org.apache.nutch.crawl.GeneratorJob.run(GeneratorJob.java:199)

at org.apache.nutch.crawl.Crawler.runTool(Crawler.java:68)

at org.apache.nutch.crawl.Crawler.run(Crawler.java:152)

at org.apache.nutch.crawl.Crawler.run(Crawler.java:250)

at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65)

at org.apache.nutch.crawl.Crawler.main(Crawler.java:257)

nutch/src/java/org/apache/nutch/crawl/GeneratorReducer.java，然后看其100行左右

batchId=new Utf8(conf.get(GeneratorJob.BATCH_ID));

改为：

int randomSeed = Math.abs(new Random().nextInt());

String batchIdStr = (System.currentTimeMillis()/1000)+"-"+randomSeed;

batchId = new Utf8( batchIdStr );

问题4.

解决

alter table webpage add batchId varchar(767) DEFAULT NULL;

然后就成功了，庆祝一下