一、前言
最近一直在研究Java8 的动态编译, 并且也被ZipFileIndex$Entry 内存泄漏所困扰,在无意中,看到一个第三方插件的动态编译。并且编译速度是原来的2-3倍。原本打算直接用这个插件,但是发现插件的编译源码存在我之前已经解决过的内存泄漏问题。所以拿其源码,进行改善。
二、第三方插件
1、maven配置
我找到的这个第三方编译插件有两个,第一个是:Talismane Utilities ,在maven仓库中可搜到相关pom的配置:
http://mvnrepository.com/search?q=Talismane+Utilities
这个插件也能编译,但是编译速度和内存泄漏问题依然存在(废弃)
第二个插件是Java Runtime Compiler , 可在Maven仓库中找到 : http://mvnrepository.com/artifact/net.openhft/compiler
我使用的版本是最新的2.3.1 , 进行反编译后:
2、插件源码更改
拿到Java Runtime Compiler插件的源码后,能找到有个CachedCompiler类,我对其compilerFromJava方法进行了更改,加上了编译options参数。具体代码如下:
-
Map<String,
byte[]> compileFromJava(
@NotNull String className,
@NotNull String javaCode,
@NotNull
final PrintWriter writer, MyJavaFileManager fileManager) {
-
Object compilationUnits;
-
if(
this.sourceDir !=
null) {
-
String filename = className.replaceAll(
"\\.",
'\\' + File.separator) +
".java";
-
File file =
new File(
this.sourceDir, filename);
-
CompilerUtils.writeText(file, javaCode);
-
compilationUnits = CompilerUtils.s_standardJavaFileManager.getJavaFileObjects(
new File[]{file});
-
}
else {
-
this.javaFileObjects.put(className,
new JavaSourceFromString(className, javaCode));
-
compilationUnits =
this.javaFileObjects.values();
-
}
-
System.setProperty(
"useJavaUtilZip",
"true");
-
List<String> options =
new ArrayList<>();
-
options.add(
"-encoding");
-
options.add(
"UTF-8");
-
options.add(
"-classpath");
-
//获取系统构建路径
-
options.add(buildClassPath());
-
//不使用SharedNameTable (jdk1.7自带的软引用,会影响GC的回收,jdk1.9已经解决)
-
options.add(
"-XDuseUnsharedTable");
-
options.add(
"-XDuseJavaUtilZip");
-
-
boolean ok = CompilerUtils.s_compiler.getTask(writer, fileManager,
new DiagnosticListener<JavaFileObject>() {
-
public void report(Diagnostic<? extends JavaFileObject> diagnostic) {
-
if(diagnostic.getKind() == Kind.ERROR) {
-
writer.println(diagnostic);
-
}
-
-
}
-
}, options, (Iterable)
null, (Iterable)compilationUnits).call().booleanValue();
-
Map<String,
byte[]> result = fileManager.getAllBuffers();
-
if(!ok) {
-
if(
this.sourceDir ==
null) {
-
this.javaFileObjects.remove(className);
-
}
-
-
return Collections.emptyMap();
-
}
else {
-
return result;
-
}
-
}
3、具体编译时测试类
利用原来的测试类,以10万个编译测试为例,进行测试,编译速度提升N倍,同时内存溢出问题也仅存在ZipFIleIndex
-
package com.yunerp.web.util.run.compile;
-
-
import com.yunerp.web.util.run.WebInterface;
-
import com.yunerp.web.util.run.dynamic.compiler.CompilerUtils;
-
-
import java.util.HashMap;
-
import java.util.Map;
-
-
public
class DynaCompTest{
-
-
public
static Map<String,Object> map =
new HashMap<>();
-
-
-
public static void main(String[] args) throws Exception {
-
-
String code =
"import java.util.HashMap;\n" +
-
"import com.yunerp.web.vaadin.message.alert;\n" +
-
"import java.util.List;\n" +
-
"import java.util.ArrayList;\n" +
-
"import com.yunerp.web.vaadin.util.modularfuntion.base.BaseUtil;\n" +
-
"import com.yunerp.web.vaadin.util.function.TableFuntionUtil;\n" +
-
"import com.yunerp.web.vaadin.util.modularfuntion.stoUtil.StoUtil;\n" +
-
"import java.util.Map;import com.yunerp.web.vaadin.util.modularfuntion.user.mini.HomePageUtil;\n" +
-
"import com.yunerp.web.util.run.WebInterface;\n" +
-
"\n" +
-
"public class web2905763164651825363 implements WebInterface {\n" +
-
" public Object execute(Map<String,Object> param) {\n" +
-
" System.out.println(param.get(\"key\")+ \"次测试编译\");" +
-
" return null;\n" +
-
" }\n" +
-
"}";
-
String name =
"web2905763164651825363";
-
-
for(
int i=
0;i<
100000;i++){
-
long time1 = System.currentTimeMillis();
-
DynamicEngine de =
new DynamicEngine();
-
try {
-
// Class cl = de.javaCodeToObject(name,code);
-
Class cl = CompilerUtils.CACHED_COMPILER.loadFromJava(name, code);
-
if (cl==
null){
-
-
System.out.println(
"编译失败/类加载失败");
-
continue;
-
}
-
WebInterface webInterface = (WebInterface)cl.newInstance();
-
Map<String,Object> param =
new HashMap<>();
-
param.put(
"key",i);
-
webInterface.execute(param);
-
}
catch (Exception e) {
-
e.printStackTrace();
-
}
-
long time2 = System.currentTimeMillis();
-
System.out.println(
"次数:"+i+
" time:"+(time2-time1));
-
}
-
-
}
-
-
}
4、编译速度对比
之前的编译代码编译速度:
使用更改后的第三方编译代码编译速度如下:
注: 因为之前的就存在ZipFileIndex问题,更改后的编译源码也只是提升编译速度,ZipFileIndex内存泄漏的问题仍然存在,目前唯一的解决方案是升级Java8 到 Java10
原文地址:https://blog.csdn.net/moneyshi/article/details/82499058