hadoop with MultiInputs, TotalOrderPartitioner-----------with hadoop-eclipse-plugins - eclipse-plugin

I have got two questions:
Now I have used hadoop0.20.203 and hadoop1.0.0. But I found that both of the two versions have no classes like MultiInputs , TotalOrderPartitioner and so on. (I open the $HADOOP_HOME/hadoop-core-1.0.0.jar file , and don't find the .class files in ort/apache/hadoop/mapreduce/lib/input/*).
But I have to use them to do some jobs. Did I miss anything? What version should I choose?
I want to find a plugins for hadoop1.0.2 ( because I found this version the hadoop-core-1.0.2.jar file has the class that I want.) I want to find one that was compiled. where can I find it?(I have got some but seems unavailable)
In a word, What my object is only to find an available hadoop---version,and plugins for eclipse. This version can deals with TotalOrder and so on. What should I do? Thanks in advance.

If they exist in 1.0.2, can you use this version instead? if your cluster currently uses 1.0.0 and you can't upgrade it to run 1.0.2, then you can get the source for these two files and add them into your job jar (as if they were code you had written).
1.0.2 is available for download from the mirrors list:
http://www.apache.org/dyn/closer.cgi/hadoop/common/
For example: http://apache.mirrorcatalogs.com/hadoop/common/hadoop-1.0.2/hadoop-1.0.2-bin.tar.gz

Related

Neo4J Plug In Won't Compile Due to Version Mismatch

I have seen variants of this question asked, but I have not seen an answer that was accepted. I am using IntelliJ IDEA to simply compile the TraversDemo sample plug in that Neo4J posted on GitHub. When I run mvn clean package I get no errors. But when I actually tried putting the .jar file into my plug ins folder on Neo4J Desktop . . . neo4j didn't recognize the plug in. So, I assumed something was wrong with my .jar file and I just tried to 'build' the java file in IntelliJ. When I did, I get this error:
Module 'TraversalPlugIn' production: java.lang.UnsupportedClassVersionError: org/neo4j/annotations/api/PublicApiAnnotationProcessor has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 54.0
I have checked and rechecked my Java (for Windows 10) is Java 8. I checked the Java Configuration GUI and asked for updates. It said I had the most recent version. Does anyone have any idea how to solve this? I already tried screwing around with various options in Build,Execution,Deployment Java compiler. No combination seemed to work.
I finally fixed this. The solution was: (i) cut existing java code (and POM file); (ii) delete original project altogether; (iii) create a new maven project but choose JDK 16 as SDK this time; and (iv) paste Java code and POM xml into new project. Then I built it, and ran maven clean package, inserted the target snapshot into the plug ins folder and ... it finally worked.

IntelliJ shows decompiled .class file instead of source code

I am having issues with IntelliJ - it shows me a "decompiled" version of the class instead of its source code if I ctrl+click the class.
This is what I see:
I am trying to open regular JDK source files.
The most relevant issue I found is explained here: Java sources replaced by decompiled files in Intellij
The most detailed answer I've found so far is there as well.
Yet it doesn't work for me:
Bytecode Viewer plugin is off.
Java Bytecode Decompiler plugin is off.
Platform, Project and Module all have same JDK version setup.
I have two JDKs available in IntelliJ: jdk1.8.0_161 and jbsdk8u112b287.2_windows_x86 (bundled with IntelliJ, but comes without src.zip). Tried with both (had to specify src.zip of jdk1.8.0_161 for jbsdk8u112b287.2_windows_x86) - no luck
src.zip is not corrupt - I can open it via WinRAR
When added jdk1.8.0_161 to IntelliJ, it automatically found src.zip. When manually adding src.zip to jbsdk8u112b287.2_windows_x86 Sourcepath tab - it started "Scanning for roots", but warned me that it "cannot determine what kind of files the chosen items contain" and offered me to "attach them as 'Sources'" so I agreed.
Tried File > Invalidate Caches / Restart... - same result.
Same issue in 2017.3 and fresh 2018.1 versions of IntelliJ.
Providing path for Documentation makes IntelliJ look for the documentation in the path specified. So it works as it should for both of JDKs. But not for sources.
Everything else works/compiles properly.
My settings:
1. Get the source files
Make sure you have downloaded and installed the source files of the JDK.
I'm on Arch Linux and installed them with pacman -S openjdk8-src which put a src.zip into /usr/lib/jvm/java-8-openjdk/. We'll use that zip file in the next step.
To list source packages of different JDK versions, do pacman -Ss "openjdk.*-src".
See this question on how to get the source files for your specific platform.
2. Point IntelliJ to the source files
In your module settings (open them with F4) under "Platform Settings" → "SDKs" → "Sourcepath", add the zip file containing the JDK source to your project JDK (be sure to pick the right JDK if IntelliJ lists more than one JDK) using the button with the plus sign:
3. Jump into the source
Select a JDK class, like Comparator, using IntelliJ's Search Everywhere or Ctrl+b with the cursor on the name of the class.
I also have the same problem. The problem for my case is that Project SDK is set to 13 [Invalid]. After I can Project SDK to a valid SDK. My problem is solved.
I tried all the things mentioned at other places for this but at the end I was doing a silly mistake. Intellij was pointing to JDK 11 for which there was no source code (I had both the SDKs 8 & 11). I removed JDK 11 and pointed to JDK 8. JDK had the source code, thus now I can see the source code on ctrl click. Also, I had disabled the bytecode viewer and decompiler plugins. Hope this helps some one.
This also happens for large files - IDEA decides to decompile them instead if indexing sources, which can take ages.
If you're willing to accept the drawdown, adding the following in Help | Edit Custom Properties might fix the problem:
idea.max.intellisense.filesize=4096
On ubuntu there was java version “OpenJDK” when I changed to “Oracle Java”, the error went away and javadoc returned
I meet same problem and finally it gone after I copy JDK to another folder and change config in IntelliJ. I think maybe cause there is a space in path before, because it is installed under "Program Files" folder.
For downloading the source code of class files belong to jar you can use download source option present on top right corner in the de-compiled class file.
On my Windows 10, expand maven:
For me going to File -> Project Structure -> Project -> SDK -> Add SDK -> Download JDK and selecting Oracle OpenJDK solved the problem. Prior to that I had a different JDK selected and apparently it didn't include source code
If you are in a maven project make sure in the project structure all the complied folders are in the excluded section.
I suggest to use Linux Instead of windows. It's easy to find and download Java.
If you are using Linux, you can download SDKMAN
Install Java by SDKMAN
# find version
$ sdk list java
# download
$ sdk install java x.y.z-amzn
ctrl+alt+shift+s add JDK
Switch project JDK
If you are using maven , Right click on Project explorer -> choose Maven -> chick on "reload projects"
This did the trick for me:
Make sure you select the option "Project Files" (instead e.g. "Project").

Golang plugin in intellij-Idea not finding all files

This relates to the go language plugin (version 0.9.15.3) for IntelliJ IDEA.
I have a directory structure in the following format:
src/
fred/
fred.go
bill/
bill.go
In (say) bill/bill.go, I import fred.go, and the compiler picks up references to fred.Something (when run from the command line).
But IntelliJ IDEA does not recognise the references to fred.Something; they come up in red, and actions such as 'go to definition' do not work.
Is there anything I can do to make this work?
I don't want to upgrade to the alpha version of the plugin if I can help it, unless it is stable (in which case, it should not be alpha).
Please don't use 0.9.15.3. The latest plugin should work properly for your case, if not please open a issue.
To get the latest plugin, please follow the instructions from here: https://github.com/go-lang-plugin-org/go-lang-idea-plugin#pre-release-builds

In "Mono 3.0.10.20" what does 20 mean?

I want to download the latest Mono MDK of the 3.0.10 branch.
On the download site, I see that 3 packages are available:
QUESTION: What is the meaning of "20" in 3.10.0.20 ?
I find it strange that the 3.0.10.20 file is older than the 3.0.10.0 file.
The Mono versioning scheme documentation does not mention it.
The 20 (or 19) is just a build number.
The package without the build number is probably supposed to be a copy of the latest package, and then someone forgot that when 3.10.0.20 was released (so it's identical to 3.10.0.19).

Importing which library?

recently I downloaded this open source project and I am trying to compile it.
However, one of the line is giving me an error.
"import com.sun.org.apache.xpath.internal.functions.WrongNumberArgsException;"
Seems that i am missing a library.... is there a way to know WHICH library do I need?
I tried searching on google for com.sun.org.apache.xpath.internal.functions,
while there seem to be a result on kickjava.com/src containing the source code.
I think i need the Jar file right?
I tried downloading xalan from apache and it didn't work.
I tried to see if there's a xpath library, but I dont think there's a xpath library?
searching for xpath led me to xalan.
I have also tried Xerces-J-bin.2.9.1 .
Thanks!
The WrongNumberArgsException class in Xalan is in the org.apache.xpath.functions package. With the Xalan jar in your project, you should just be able to change the import statement in the open source code to use the correct path.
The OpenSource author (what ever "this open source project" is) imported the internal exception class from the sun adopted xalan classes in Java 6. This should not be done at all! Will not work with older VMs and may be broken with later ones.
Never import com.sun.*!