GroovyScriptEngine无法加载正在运行的groovy脚本的导入

Question

背景:

我最近开始使用Groovy，并试图在eclipse插件中嵌入一个groovy脚本引擎，以便我的客户在基于eclipse的产品中开发自己的GUI扩展。这与在可德豪斯网站上发布的http://groovy.codehaus.org/Integrating+Groovy+in+an+application+-+a+success+story非常相似。

问题

在尝试加载groovy类( "main_eclipse.groovy")时，GroovyScriptEngine抛出从eclipse插件运行的groovy脚本(我们称之为“SwtGuiBuilder”)，并出现以下错误：

虫子！在已经迭代的同时排队新的源。排队的源是'file:/home/nicolas/workspace/groovy-test/src/gui/SwtGuiBuilder.groovy‘

问题

有人遇到过同样的问题吗？怎么能修好呢？任何帮助都将不胜感激！

一些意见：

• 当使用groovy解释器而不是GroovyScriptEngine java对象时，使用SwtGuiBuilder类没有问题(请参阅下面的脚本"main_groovy“)。
• 我的问题似乎不是类路径问题，因为在抛出的异常中提到了包含我的SwtGuiBuilder类的文件。
• 在两个报告的groovy错误中提到了错误消息，GRECLIPSE-429和GRECLIPSE-1037。我没有完全了解技术细节，但这些but似乎与加载大量类时的性能问题有关，这与我的情况无关.

详细信息

SampleView.java

public class SampleView
{
public SampleView() { super(); }

public void createPartControl(Composite parent) 
{
    String    groovyScript = null;
    String [] groovyPath   = null;

    boolean shall_exit = false;
    do
    {      // ask user for params
        GroovyLocationDialog groovyLocationDialog= new GroovyLocationDialog(parent.getShell() );
        int return_code = groovyLocationDialog.open();
        if ( return_code != Window.OK )
            shall_exit = true;
        else 
        {
            groovyScript= groovyLocationDialog.getInputScriptName();
            groovyPath  = groovyLocationDialog.getInputScriptPath();

            // run it
            ScriptConnector scriptConnector = new ScriptConnector(parent);
            try                 { scriptConnector.runGuiComponentScript( groovyPath, groovyScript); }
            catch (Exception e) { e.printStackTrace(); }
            System.out.println("script finished");
        }
    }
    while ( ! shall_exit );
}

ScriptConnector.java

public class ScriptConnector
{
    private String[]  roots;
    private Composite window;
    private Binding   binding;

    public ScriptConnector( Composite window )
    {
         this.window    = window;
         Binding  scriptenv = new Binding();    // A new Binding is created ...
         scriptenv.setVariable("SDE", this); 
         scriptenv.setVariable("WINDOW", this.window); // ref to current window

         this.binding = scriptenv;
    }

    public void runGuiComponentScript(final String[] groovyPath, final String scriptName) 
    {
        GroovyScriptEngine gse = null;
        this.roots     = groovyPath;
        try 
        {
            // instanciating the script engine with current classpath
            gse = new GroovyScriptEngine( roots, this.getClass().getClassLoader() );
            gse.run(scriptName, binding);      // ... and run specified script
        }
        catch (Exception e) { e.printStackTrace(); }
        catch (Throwable t) { t.printStackTrace(); }
    }
}

main_eclipse.groovy

package launcher;

import org.eclipse.swt.SWT
import org.eclipse.swt.widgets.*
import org.eclipse.swt.events.*;
import org.eclipse.swt.layout.RowLayout as Layout

// This import will fail...
import gui.SwtGuiBuilder;


WINDOW.layout = new Layout(SWT.VERTICAL);
def builder = new SwtGuiBuilder(WINDOW);
builder.Label ( style=SWT.NONE, text = 'Simple demo of Groovy and SWT')
builder.Button( style=SWT.PUSH, text = 'Click me' , action = { println "Click !" } )

SwtGuiBuilder.groovy

package gui;

import org.eclipse.swt.events.*
import org.eclipse.swt.widgets.Button
import org.eclipse.swt.widgets.Composite
import org.eclipse.swt.widgets.Label


class SwtGuiBuilder
{
    private Composite _parent

    public SwtGuiBuilder(Composite parent) { _parent = parent }

    public void Button( style = SWT.PUSH, text= null, action = null )
    {
        def btn = new Button(_parent, style)
        if ( text != null )
            btn.text = text
        if (action != null)
            btn.addSelectionListener( new SelectionAdapter() { void widgetSelected( SelectionEvent event ) { action(); } } );
    }

    public void Label( style = SWT.NONE, text = '' )
    {
        def lbl = new Label(_parent, style)
        lbl.text = text
    }
}

main_groovy.groovy

package launcher;

import org.eclipse.swt.SWT
import org.eclipse.swt.widgets.*
import org.eclipse.swt.events.*;
import org.eclipse.swt.layout.RowLayout as Layout

// ... But this import is handled properly !
import gui.SwtGuiBuilder;

def display = new Display()
def WINDOW = new Shell(display)
WINDOW.text = 'Groovy / SWT Test';

WINDOW.layout = new Layout(SWT.VERTICAL);
def builder = new SwtGuiBuilder(WINDOW);
builder.Label ( style=SWT.NONE, text = 'Simple demo of Groovy and SWT')
builder.Button( style=SWT.PUSH, text = 'Click me' , action = { println "Ya clicked me !" } )

WINDOW.pack();
WINDOW.open();

while (!WINDOW.disposed) {
    if (!WINDOW.display.readAndDispatch())
        WINDOW.display.sleep();
}

堆栈跟踪

虫子！在已经迭代的同时排队新的源。排队的源是'file:/home/nicolas/workspace/groovy-test/src/gui/SwtGuiBuilder.groovy‘at org.codehaus.groovy.control.CompilationUnit.addSource(CompilationUnit.java:460) at org.codehaus.groovy.control.CompilationUnit.addSource(CompilationUnit.java:433) at groovy.util.GroovyScriptEngine$ScriptClassLoader$3.findClassNode(GroovyScriptEngine.java:195) at org.codehaus.groovy.control.ClassNodeResolver.resolveName(ClassNodeResolver.java:124) at org.codehaus.groovy.control.ResolveVisitor.resolveToOuter(在org.codehaus.groovy.control.ResolveVisitor.resolve(ResolveVisitor.java:377)，org.codehaus.groovy.control.ResolveVisitor.visitClass(ResolveVisitor.java:1407)，org.codehaus.groovy.control.ResolveVisitor.startResolving(ResolveVisitor.java:202)，org.codehaus.groovy.control.CompilationUnit$1.call(CompilationUnit.java:713)，org.codehaus.groovy.control.CompilationUnit.applyToSourceUnits(CompilationUnit.java:1015)，org.codehaus.groovy。control.CompilationUnit.doPhaseOperation(CompilationUnit.java:647) at org.codehaus.groovy.control.CompilationUnit.compile(CompilationUnit.java:596) at groovy.lang.GroovyClassLoader.doParseClass(GroovyClassLoader.java:279) at groovy.lang.GroovyClassLoader.parseClass(GroovyClassLoader.java:258) at groovy.util.GroovyScriptEngine$ScriptClassLoader.doParseClass(GroovyScriptEngine.java:247) at groovy.util.GroovyScriptEngine$ScriptClassLoader.parseClass(GroovyScriptEngine.java:229) at groovy.lang.GroovyClassLoader.parseClass(GroovyClassLoader.java:244)在groovy.lang.GroovyClassLoader.parseClass(GroovyClassLoader.java:202) at groovy.util.GroovyScriptEngine.loadScriptByName(GroovyScriptEngine.java:514) at groovy.util.GroovyScriptEngine.createScript(GroovyScriptEngine.java:564) at groovy.util.GroovyScriptEngine.run(GroovyScriptEngine.java:551)

我的配置：

• LinuxUbuntu14.04 x86
• Groovy版本: 2.3.2
• JVM: 1.7.0_55
• 日食开普勒SR2 -构建20140224-0627
• Eclipse插件v2.0.7

Answer 1

我没有使用GroovyScriptEngine，而是使用了GroovyShell类(下面是groovy代码，但很容易更改为java)，CompilerConfiguration允许您指定类路径。

    def config = new CompilerConfiguration(classpath: classpath)
    def binding = new Binding()

    def result = new GroovyShell(binding, config).evaluate("""
def foo='bar'
""")