Create CommandBuilder class with basic functionality

Author: James Hagborg

src/main/java/org/usfirst/frc/team69/util/CommandBuilder.java

@@ -0,0 +1,99 @@
+package org.usfirst.frc.team69.util;
+
+import edu.wpi.first.wpilibj.command.Command;
+import edu.wpi.first.wpilibj.command.CommandGroup;
+
+/**
+ * A builder class to create commands in autonomous.  Currently, it wraps a
+ * {@link CommandGroup}, but the implementation may change in future versions.
+ * 
+ * To build a command, add child commands using {@link #sequential(Command)}
+ * and {@link #parallel(Command)}, then get a command using {@link #build()}.
+ * 
+ * @author James
+ *
+ */
+public class CommandBuilder {
+    private final CommandGroup m_cmdGroup;
+    
+    /**
+     * Construct a new CommandBuilder
+     */
+    public CommandBuilder() {
+        m_cmdGroup = new CommandGroup();
+    }
+    
+    /**
+     * Construct a new CommandBuilder with a given name
+     * @param name The name of the command to build
+     */
+    public CommandBuilder(String name) {
+        m_cmdGroup = new CommandGroup(name);
+    }
+    
+    /**
+     * Add a command in sequence.  Execution of the next command will not
+     * happen until this one finishes.
+     * @param command The command to add in sequence
+     * @return This CommandBuilder object
+     */
+    public CommandBuilder sequential(Command command) {
+        m_cmdGroup.addSequential(command);
+        return this;
+    }
+    
+    /**
+     * Add a command in sequence.  Execution of the next command will not
+     * happen until this one finishes, or until the timeout expires
+     * @param command The command to add in sequence
+     * @param timeout The timeout, in seconds
+     * @return This CommandBuilder object
+     */
+    public CommandBuilder sequential(Command command, double timeout) {
+        m_cmdGroup.addSequential(command, timeout);
+        return this;
+    }
+    
+    /**
+     * Add a command in parallel.  Execution of the next command will begin
+     * immediately, while this one continues to execute in parallel.
+     * 
+     * Note that the command created will not end until all parallel commands
+     * finish.
+     * 
+     * @param command The command to add in parallel
+     * @return This CommandBuilder object
+     */
+    public CommandBuilder parallel(Command command) {
+        m_cmdGroup.addParallel(command);
+        return this;
+    }
+    
+    /**
+     * Add a command in parallel.  Execution of the next command will begin
+     * immediately, while this one continues to execute in parallel.  The
+     * command will be killed if the timeout expires.
+     * 
+     * Note that the command created will not end until all parallel commands
+     * finish.
+     * 
+     * @param command The command to add in parallel
+     * @param timeout The timeout, in seconds
+     * @return This CommandBuilder object
+     */
+    public CommandBuilder parallel(Command command, double timeout) {
+        m_cmdGroup.addParallel(command, timeout);
+        return this;
+    }
+    
+    /**
+     * Build a command.  Note that for simplicity, calling this method 
+     * multiple times will return the same {@link Command} object.  This
+     * may change in the future, to match the behavior of other objects
+     * following the builder pattern.
+     * @return A command created from this builder
+     */
+    public Command build() {
+        return m_cmdGroup;
+    }
+}