Compiling(Building) Changes(fixes) .class while I don't need that.

So basically I'm new to java,(Well i came from C# so its almost the same),
I started working on some emulated server files,
In this case :
I decompile whole .jar , file full of .class files,
In eclipse started new project (around the folder where i extracted source)
And new project was made perfectly (Ofcorse lot of errors where in there, but just because i decompile and use just one .jar file out of package and that shouldn't be the problem) The main problem for me, is when i try to build project it compiles .java files to .class files perfectly, Just the thing java compiler dose is
Fixes errors...
for example I had :
config.java(Not compiled yet)
.java file (before building project)

Code:

---

import gnu.trove.TIntIntHashMap;
import gnu.trove.TIntObjectHashMap;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.math.BigInteger;
import java.util.Arrays;
import java.util.List;
import java.util.Properties;
import java.util.StringTokenizer;
import java.util.logging.Logger;
import javolution.util.FastList;
import net.sf.l2j.gameserver.util.FloodProtectorConfig;
import net.sf.l2j.util.StringUtil;

---

And after fixing and cleaning It results me with .class files like it :

.class file (after building project)

Code:

---

package net.sf.l2j;

import FastList;
import TIntIntHashMap;
import TIntObjectHashMap;
import java.io.File;
import java.util.List;
import java.util.Properties;
import java.util.logging.Logger;
import net.sf.l2j.gameserver.util.FloodProtectorConfig;

---

Since i wanna same old file just with my custom edits without any fixes with all errors kept,
How can i achieve that? Maybe i should download any other builder/compiler for eclipse as plugin or something?
Thank you for help.

You have allowed Eclipse to automatically fix your code; go to Project>Properties and (de)select everything you like; especially the Java Code Style>Organize Imports part and the Java Compiler>Building part have a lot of settings that can be dis- or enabled.

kind regards,

Jos

I already did that I changed every setting tried everything don't even know what to try next...
I think it's about javac compiler not even about eclipse... cuz when i try compile in cmd i get errors and file don't compiles...
How can I just compile .java files to .class skiping all errors ? ;/ Cuz in eclipse settings nothing help's / works.
And It's so frustrating...
Maybe someone can offer any Guide or at last some other compiler that would Ignore Errors in code, (Cuz for me they are expected errors and should be kept)
Any suggestion would help, thank you.