From 799cb9486377f98921ba71bae22717e15bcd0a51 Mon Sep 17 00:00:00 2001 From: "Shawn O. Pearce" Date: Mon, 21 Jul 2008 01:18:23 -0400 Subject: [PATCH] Create a lightweight registration wrapper for TextBuiltin Automatic command list generation requires knowing what commands are available to this runtime, and what name those commands can be called as by the end-user. This lightweight wrappers carries the data from the Command annotation, possibly filling in the name of the command by generating it from the implementation class name. Signed-off-by: Shawn O. Pearce --- .../src/org/spearce/jgit/pgm/CommandRef.java | 151 +++++++++++++++++++++ 1 file changed, 151 insertions(+) create mode 100644 org.spearce.jgit.pgm/src/org/spearce/jgit/pgm/CommandRef.java diff --git a/org.spearce.jgit.pgm/src/org/spearce/jgit/pgm/CommandRef.java b/org.spearce.jgit.pgm/src/org/spearce/jgit/pgm/CommandRef.java new file mode 100644 index 00000000..40400a72 --- /dev/null +++ b/org.spearce.jgit.pgm/src/org/spearce/jgit/pgm/CommandRef.java @@ -0,0 +1,151 @@ +/* + * Copyright (C) 2008, Shawn O. Pearce + * + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * + * - Neither the name of the Git Development Community nor the + * names of its contributors may be used to endorse or promote + * products derived from this software without specific prior + * written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND + * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +package org.spearce.jgit.pgm; + +import java.lang.reflect.Constructor; +import java.lang.reflect.InvocationTargetException; + +/** + * Description of a command (a {@link TextBuiltin} subclass. + *

+ * These descriptions are lightweight compared to creating a command instance + * and are therefore suitable for catalogs of "known" commands without linking + * the command's implementation and creating a dummy instance of the command. + */ +public class CommandRef { + private final Class impl; + + private final String name; + + private String usage; + + boolean common; + + CommandRef(final Class clazz) { + this(clazz, guessName(clazz)); + } + + CommandRef(final Class clazz, final Command cmd) { + this(clazz, cmd.name().length() > 0 ? cmd.name() : guessName(clazz)); + usage = cmd.usage(); + common = cmd.common(); + } + + private CommandRef(final Class clazz, final String cn) { + impl = clazz; + name = cn; + usage = ""; + } + + private static String guessName(final Class clazz) { + final StringBuilder s = new StringBuilder(); + if (clazz.getName().startsWith("org.spearce.jgit.pgm.debug.")) + s.append("debug-"); + + boolean lastWasDash = true; + for (final char c : clazz.getSimpleName().toCharArray()) { + if (Character.isUpperCase(c)) { + if (!lastWasDash) + s.append('-'); + lastWasDash = !lastWasDash; + s.append(Character.toLowerCase(c)); + } else { + s.append(c); + } + } + return s.toString(); + } + + /** + * @return name the command is invoked as from the command line. + */ + public String getName() { + return name; + } + + /** + * @return one line description of the command's feature set. + */ + public String getUsage() { + return usage; + } + + /** + * @return true if this command is considered to be commonly used. + */ + public boolean isCommon() { + return common; + } + + /** + * @return name of the Java class which implements this command. + */ + public String getImplementationClassName() { + return impl.getName(); + } + + /** + * @return a new instance of the command implementation. + */ + public TextBuiltin create() { + final Constructor c; + try { + c = impl.getDeclaredConstructor(); + } catch (SecurityException e) { + throw new RuntimeException("Cannot create command " + getName(), e); + } catch (NoSuchMethodException e) { + throw new RuntimeException("Cannot create command " + getName(), e); + } + c.setAccessible(true); + + final TextBuiltin r; + try { + r = c.newInstance(); + } catch (InstantiationException e) { + throw new RuntimeException("Cannot create command " + getName(), e); + } catch (IllegalAccessException e) { + throw new RuntimeException("Cannot create command " + getName(), e); + } catch (IllegalArgumentException e) { + throw new RuntimeException("Cannot create command " + getName(), e); + } catch (InvocationTargetException e) { + throw new RuntimeException("Cannot create command " + getName(), e); + } + r.setCommandName(getName()); + return r; + } +} -- 2.11.4.GIT