如何以完整的类名从eclipse中以编程方式查找java文件？

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.OperationCanceledException;
import org.eclipse.jdt.core.IJavaElement;
import org.eclipse.jdt.core.IJavaProject;
import org.eclipse.jdt.core.IType;
import org.eclipse.jdt.core.JavaCore;
import org.eclipse.jdt.core.JavaModelException;
import org.eclipse.jdt.core.search.IJavaSearchConstants;
import org.eclipse.jdt.core.search.IJavaSearchScope;
import org.eclipse.jdt.core.search.SearchEngine;
import org.eclipse.jdt.core.search.SearchParticipant;
import org.eclipse.jdt.core.search.SearchPattern;
import org.eclipse.jdt.core.search.TypeNameMatch;
import org.eclipse.jdt.core.search.TypeNameMatchRequestor;

public class JavaFileFinder {

    public static void main(String[] args) {
        String className = "com.example.MyClass";
        IType type = findJavaFile(className);
        if (type != null) {
            IFile file = (IFile) type.getResource();
            System.out.println("Java文件路径：" + file.getFullPath());
        } else {
            System.out.println("未找到Java文件");
        }
    }

    public static IType findJavaFile(String className) {
        IJavaProject[] projects = JavaCore.create(ResourcesPlugin.getWorkspace().getRoot())
                .getJavaProjects();
        for (IJavaProject project : projects) {
            try {
                IType type = findJavaFileInProject(project, className);
                if (type != null) {
                    return type;
                }
            } catch (JavaModelException e) {
                e.printStackTrace();
            }
        }
        return null;
    }

    public static IType findJavaFileInProject(IJavaProject project, String className)
            throws JavaModelException {
        IJavaSearchScope scope = SearchEngine.createJavaSearchScope(new IJavaElement[] { project });
        SearchPattern pattern = SearchPattern.createPattern(className,
                IJavaSearchConstants.TYPE, IJavaSearchConstants.DECLARATIONS, SearchPattern.R_EXACT_MATCH);
        TypeNameMatchRequestor requestor = new TypeNameMatchRequestor() {
            private IType type;

            @Override
            public void acceptTypeNameMatch(TypeNameMatch match) {
                if (type == null) {
                    type = match.getType();
                }
            }

            public IType getType() {
                return type;
            }
        };
        new SearchEngine().search(pattern, new SearchParticipant[] { SearchEngine.getDefaultSearchParticipant() },
                scope, requestor, new NullProgressMonitor());
        return requestor.getType();
    }
}