Cannot complete the install because one or more required items could not be found.
Software being installed: Maven Integration for Eclipse (Required) 0.12.1.20110112-1712 (org.maven.ide.eclipse.feature.feature.group 0.12.1.20110112-1712)
Missing requirement: Maven Integration for Eclipse (Editors) 0.12.1.20110112-1712 (org.maven.ide.eclipse.editor 0.12.1.20110112-1712) requires 'bundle org.eclipse.zest.core 0.0.0' but it could not be found
Cannot satisfy dependency:
From: Maven Integration for Eclipse (Required) 0.12.1.20110112-1712 (org.maven.ide.eclipse.feature.feature.group 0.12.1.20110112-1712)
To: org.maven.ide.eclipse.editor [0.12.1.20110112-1712]
解决方案：
Help -> Install new Software ->Available Software Sites -> choose "http://download.eclipse.org/tools/gef/updates/releases/" -> Enable it -> then install.
Or if don't have, choose Add "http://download.eclipse.org/tools/gef/updates/releases/" -> then install.
After finish installing, restart eclipse, can install maven plugin.
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An error occurred while collecting items to be installed session context was:(profile=epp.package.jee, phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=). Unable to read repository at http://m2eclipse.sonatype.org/sites/m2e/0.12.1.20110112-1712/plugins/org.maven.ide.eclipse.maven_embedder_0.12.1.20110112-1712.jar. Read timed out
解决方案：
change another address:
http://download.eclipse.org/technology/m2e/releases