Allow to read configured keys

Currently, there is no way to read the content
of the Git Configuration in a  way that would
allow to list all configured values generically.
This change extends the Config class in such a
way as to being able to get a list of sections and
to get a list of names for any given section or
subsection.
This is required in able to implement proper
configuration handling in EGit (show all the
content of a given configuration similar to 
"git config -l").

Change-Id: Idd4bc47be18ed0e36b11be8c23c9c707159dc830
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>

1 files changed, 101 insertions, 0 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/Config.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/Config.java
index 7c5af1e648..ccb2516917 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/Config.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/Config.java
@@ -372,6 +372,33 @@ public class Config {
 	}
 
 	/**
+	 * @return the sections defined in this {@link Config}
+	 */
+	public Set<String> getSections() {
+		return get(new SectionNames());
+	}
+
+	/**
+	 * @param section
+	 *            the section
+	 * @return the list of names defined for this section
+	 */
+	public Set<String> getNames(String section) {
+		return getNames(section, null);
+	}
+
+	/**
+	 * @param section
+	 *            the section
+	 * @param subsection
+	 *            the subsection
+	 * @return the list of names defined for this subsection
+	 */
+	public Set<String> getNames(String section, String subsection) {
+		return get(new NamesInSection(section, subsection));
+	}
+
+	/**
 	 * Obtain a handle to a parsed set of configuration values.
 	 *
 	 * @param <T>
@@ -1077,6 +1104,80 @@ public class Config {
 		}
 	}
 
+	private static class NamesInSection implements SectionParser<Set<String>> {
+		private final String section;
+
+		private final String subsection;
+
+		NamesInSection(final String sectionName, final String subSectionName) {
+			section = sectionName;
+			subsection = subSectionName;
+		}
+
+		@Override
+		public int hashCode() {
+			final int prime = 31;
+			int result = 1;
+			result = prime * result + section.hashCode();
+			result = prime * result
+					+ ((subsection == null) ? 0 : subsection.hashCode());
+			return result;
+		}
+
+		@Override
+		public boolean equals(Object obj) {
+			if (this == obj)
+				return true;
+			if (obj == null)
+				return false;
+			if (getClass() != obj.getClass())
+				return false;
+			NamesInSection other = (NamesInSection) obj;
+			if (!section.equals(other.section))
+				return false;
+			if (subsection == null) {
+				if (other.subsection != null)
+					return false;
+			} else if (!subsection.equals(other.subsection))
+				return false;
+			return true;
+		}
+
+		public Set<String> parse(Config cfg) {
+			final Set<String> result = new HashSet<String>();
+			while (cfg != null) {
+				for (final Entry e : cfg.state.get().entryList) {
+					if (e.name != null
+							&& StringUtils.equalsIgnoreCase(e.section, section)) {
+						if (subsection == null && e.subsection == null)
+							result.add(StringUtils.toLowerCase(e.name));
+						else if (e.subsection != null
+								&& e.subsection.equals(subsection))
+							result.add(StringUtils.toLowerCase(e.name));
+
+					}
+				}
+				cfg = cfg.baseConfig;
+			}
+			return Collections.unmodifiableSet(result);
+		}
+	}
+
+	private static class SectionNames implements SectionParser<Set<String>> {
+		public Set<String> parse(Config cfg) {
+			final Set<String> result = new HashSet<String>();
+			while (cfg != null) {
+				for (final Entry e : cfg.state.get().entryList) {
+					if (e.section != null)
+						result.add(StringUtils.toLowerCase(e.section));
+				}
+				cfg = cfg.baseConfig;
+			}
+			return Collections.unmodifiableSet(result);
+		}
+	}
+
+
 	private static class State {
 		final List<Entry> entryList;