eclipse - 由于缺少必需的项目，插件安装失败

Question

我尝试为 Eclipse 安装 Web Tool Platform，但由于以下错误而无法成功。

Cannot complete the install because one or more required items could not be found.
Software being installed: CXF Web Services 1.1.0.v201201312103-7H79FHxFAKlbotH5e9l3vAA6MBG (org.eclipse.jst.ws.cxf.feature.feature.group 1.1.0.v201201312103-7H79FHxFAKlbotH5e9l3vAA6MBG) Missing requirement: Java EE Component 1.1.501.v201108102200 (org.eclipse.jst.j2ee 1.1.501.v201108102200) requires 'bundle org.eclipse.emf.codegen [2.2.0,3.0.0)' but it could not be found
Missing requirement: Java EE Component 1.1.501.v201109131730 (org.eclipse.jst.j2ee 1.1.501.v201109131730) requires 'bundle org.eclipse.emf.codegen [2.2.0,3.0.0)' but it could not be found
Missing requirement: Java EE Component 1.1.600.v201203142300 (org.eclipse.jst.j2ee 1.1.600.v201203142300) requires 'bundle org.eclipse.emf.codegen [2.2.0,3.0.0)' but it could not be found
Missing requirement: Java EE Component 1.1.600.v201205030130 (org.eclipse.jst.j2ee 1.1.600.v201205030130) requires 'bundle org.eclipse.emf.codegen [2.2.0,3.0.0)' but it could not be found
Missing requirement: Java EE Component 1.1.600.v201205170400 (org.eclipse.jst.j2ee 1.1.600.v201205170400) requires 'bundle org.eclipse.emf.codegen [2.2.0,3.0.0)' but it could not be found
Missing requirement: Java EE Component 1.1.601.v201207101600 (org.eclipse.jst.j2ee 1.1.601.v201207101600) requires 'bundle org.eclipse.emf.codegen [2.2.0,3.0.0)' but it could not be found
Cannot satisfy dependency: From: CXF Web Services Core 1.1.0.v201205012246 (org.eclipse.jst.ws.cxf.core 1.1.0.v201205012246) To: bundle org.eclipse.jst.j2ee [1.1.0,1.2.0) Cannot satisfy dependency: From: CXF Web Services 1.1.0.v201201312103-7H79FHxFAKlbotH5e9l3vAA6MBG (org.eclipse.jst.ws.cxf.feature.feature.group 1.1.0.v201201312103-7H79FHxFAKlbotH5e9l3vAA6MBG) To: org.eclipse.jst.ws.cxf.core [1.1.0.v201205012246]

实际上，当我尝试通过帮助>安装新软件安装其他软件时，这种情况发生了很多次。例如。我在尝试安装 Android SDK 时遇到过几次。
虽然我通常可以在摆弄它的同时解决它，但我不敢相信安装插件是如此痛苦。

所以我想我可能错过了一些非常基本的东西，但我找不到提示。因此，如果您能帮助我解决这个特定问题，同时提供一些如何在更一般的问题上解决此类问题的信息，那就太好了。

Answer 1

在“安装”对话框的底部，确保选中“在安装过程中联系所有更新站点以查找所需的软件”。

这假设必要的默认软件站点仍然正确配置(尚未禁用、删除等)并且可用。这些是在 Windows、首选项、安装/更新、可用软件站点下配置的。 (不幸的是，我在这里没有看到“恢复默认值”按钮。)对于至少最新版本的 Eclipse (4.2/Juno)，您需要确保至少在此处配置并启用了以下站点:

• 朱诺:http://download.eclipse.org/releases/juno
• Eclipse 项目更新:http://download.eclipse.org/eclipse/updates/4.2
• Eclipse Web Tools Platform (WTP) 软件存储库:http://download.eclipse.org/webtools/repository/juno