gerrit-pgm/src/main/java/com/google/gerrit/pgm/util/ConsoleUI.java - gerrit - Git at Google

 // Copyright (C) 2009 The Android Open Source Project
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 // http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 package com.google.gerrit.pgm.util;

 import static org.eclipse.jgit.util.StringUtils.equalsIgnoreCase;

 import java.io.Console;
 import java.lang.reflect.InvocationTargetException;
 import java.util.Set;

 /** Console based interaction with the invoking user. */
 public abstract class ConsoleUI {
   /** Get a UI instance, assuming interactive mode. */
   public static ConsoleUI getInstance() {
     return getInstance(false);
   }

   /** Get a UI instance, possibly forcing batch mode. */
   public static ConsoleUI getInstance(final boolean batchMode) {
     Console console = batchMode ? null : System.console();
     return console != null ? new Interactive(console) : new Batch();
   }

   /** Constructs an exception indicating the user aborted the operation. */
   protected static Die abort() {
     return new Die("aborted by user");
   }

   /** Obtain all values from an enumeration. */
   @SuppressWarnings("unchecked")
   protected static <T extends Enum<?>> T[] all(final T value) {
     try {
       return (T[]) value.getClass().getMethod("values").invoke(null);
     } catch (IllegalArgumentException e) {
       throw new IllegalArgumentException("Cannot obtain enumeration values", e);
     } catch (SecurityException e) {
       throw new IllegalArgumentException("Cannot obtain enumeration values", e);
     } catch (IllegalAccessException e) {
       throw new IllegalArgumentException("Cannot obtain enumeration values", e);
     } catch (InvocationTargetException e) {
       throw new IllegalArgumentException("Cannot obtain enumeration values", e);
     } catch (NoSuchMethodException e) {
       throw new IllegalArgumentException("Cannot obtain enumeration values", e);
     }
   }

   /** @return true if this is a batch UI that has no user interaction. */
   public abstract boolean isBatch();

   /** Display a header message before a series of prompts. */
   public abstract void header(String fmt, Object... args);

   /** Display a message. */
   public abstract void message(String fmt, Object... args);

   /** Request the user to answer a yes/no question. */
   public abstract boolean yesno(Boolean def, String fmt, Object... args);

   /** Prints a message asking the user to let us know when its safe to continue. */
   public abstract void waitForUser();

   /** Prompt the user for a string, suggesting a default, and returning choice. */
   public abstract String readString(String def, String fmt, Object... args);

   /** Prompt the user to make a choice from an allowed list of values. */
   public abstract String readString(String def, Set<String> allowedValues,
       String fmt, Object... args);

   /** Prompt the user for an integer value, suggesting a default. */
   public int readInt(int def, String fmt, Object... args) {
     for (;;) {
       String p = readString(String.valueOf(def), fmt, args);
       try {
         return Integer.parseInt(p.trim(), 10);
       } catch (NumberFormatException e) {
         System.err.println("error: Invalid integer format: " + p.trim());
       }
     }
   }

   /** Prompt the user for a password, returning the string; null if blank. */
   public abstract String password(String fmt, Object... args);

   /** Prompt the user to make a choice from an enumeration's values. */
   public abstract <T extends Enum<?>> T readEnum(T def, String fmt,
       Object... args);

   private static class Interactive extends ConsoleUI {
     private final Console console;

     Interactive(final Console console) {
       this.console = console;
     }

     @Override
     public boolean isBatch() {
       return false;
     }

     @Override
     public boolean yesno(Boolean def, String fmt, Object... args) {
       final String prompt = String.format(fmt, args);
       for (;;) {
         String y = "y";
         String n = "n";
         if (def != null) {
           if (def) {
             y = "Y";
           } else {
             n = "N";
           }
         }

         String yn = console.readLine("%-30s [%s/%s]? ", prompt, y, n);
         if (yn == null) {
           throw abort();
         }
         yn = yn.trim();
         if (def != null && yn.isEmpty()) {
           return def;
         }
         if (yn.equalsIgnoreCase("y") || yn.equalsIgnoreCase("yes")) {
           return true;
         }
         if (yn.equalsIgnoreCase("n") || yn.equalsIgnoreCase("no")) {
           return false;
         }
       }
     }

     @Override
     public void waitForUser() {
       if (console.readLine("Press enter to continue ") == null) {
         throw abort();
       }
     }

     @Override
     public String readString(String def, String fmt, Object... args) {
       final String prompt = String.format(fmt, args);
       String r;
       if (def != null) {
         r = console.readLine("%-30s [%s]: ", prompt, def);
       } else {
         r = console.readLine("%-30s : ", prompt);
       }
       if (r == null) {
         throw abort();
       }
       r = r.trim();
       if (r.isEmpty()) {
         return def;
       }
       return r;
     }

     @Override
     public String readString(String def, Set<String> allowedValues, String fmt,
         Object... args) {
       for (;;) {
         String r = readString(def, fmt, args);
         if (allowedValues.contains(r.toLowerCase())) {
           return r.toLowerCase();
         }
         if (!"?".equals(r)) {
           console.printf("error: '%s' is not a valid choice\n", r);
         }
         console.printf("       Supported options are:\n");
         for (final String v : allowedValues) {
           console.printf("         %s\n", v.toString().toLowerCase());
         }
       }
     }

     @Override
     public String password(String fmt, Object... args) {
       final String prompt = String.format(fmt, args);
       for (;;) {
         final char[] a1 = console.readPassword("%-30s : ", prompt);
         if (a1 == null) {
           throw abort();
         }

         final char[] a2 = console.readPassword("%30s : ", "confirm password");
         if (a2 == null) {
           throw abort();
         }

         final String s1 = new String(a1);
         final String s2 = new String(a2);
         if (!s1.equals(s2)) {
           console.printf("error: Passwords did not match; try again\n");
           continue;
         }
         return !s1.isEmpty() ? s1 : null;
       }
     }

     @Override
     public <T extends Enum<?>> T readEnum(T def, String fmt, Object... args) {
       final String prompt = String.format(fmt, args);
       final T[] options = all(def);
       for (;;) {
         String r = console.readLine("%-30s [%s/?]: ", prompt, def.toString());
         if (r == null) {
           throw abort();
         }
         r = r.trim();
         if (r.isEmpty()) {
           return def;
         }
         for (final T e : options) {
           if (equalsIgnoreCase(e.toString(), r)) {
             return e;
           }
         }
         if (!"?".equals(r)) {
           console.printf("error: '%s' is not a valid choice\n", r);
         }
         console.printf("       Supported options are:\n");
         for (final T e : options) {
           console.printf("         %s\n", e.toString().toLowerCase());
         }
       }
     }

     @Override
     public void header(String fmt, Object... args) {
       fmt = fmt.replaceAll("\n", "\n*** ");
       console.printf("\n*** " + fmt + "\n*** \n\n", args);
     }

     @Override
     public void message(String fmt, Object... args) {
       console.printf(fmt, args);
     }
   }

   private static class Batch extends ConsoleUI {
     @Override
     public boolean isBatch() {
       return true;
     }

     @Override
     public boolean yesno(Boolean def, String fmt, Object... args) {
       return def != null ? def : true;
     }

     @Override
     public String readString(String def, String fmt, Object... args) {
       return def;
     }

     @Override
     public String readString(String def, Set<String> allowedValues, String fmt,
         Object... args) {
       return def;
     }

     @Override
     public void waitForUser() {
     }

     @Override
     public String password(String fmt, Object... args) {
       return null;
     }

     @Override
     public <T extends Enum<?>> T readEnum(T def, String fmt, Object... args) {
       return def;
     }

     @Override
     public void header(String fmt, Object... args) {
     }

     @Override
     public void message(String fmt, Object... args) {
     }
   }
 }
	// Copyright (C) 2009 The Android Open Source Project
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	package com.google.gerrit.pgm.util;

	import static org.eclipse.jgit.util.StringUtils.equalsIgnoreCase;

	import java.io.Console;
	import java.lang.reflect.InvocationTargetException;
	import java.util.Set;

	/** Console based interaction with the invoking user. */
	public abstract class ConsoleUI {
	/** Get a UI instance, assuming interactive mode. */
	public static ConsoleUI getInstance() {
	return getInstance(false);
	}

	/** Get a UI instance, possibly forcing batch mode. */
	public static ConsoleUI getInstance(final boolean batchMode) {
	Console console = batchMode ? null : System.console();
	return console != null ? new Interactive(console) : new Batch();
	}

	/** Constructs an exception indicating the user aborted the operation. */
	protected static Die abort() {
	return new Die("aborted by user");
	}

	/** Obtain all values from an enumeration. */
	@SuppressWarnings("unchecked")
	protected static <T extends Enum<?>> T[] all(final T value) {
	try {
	return (T[]) value.getClass().getMethod("values").invoke(null);
	} catch (IllegalArgumentException e) {
	throw new IllegalArgumentException("Cannot obtain enumeration values", e);
	} catch (SecurityException e) {
	throw new IllegalArgumentException("Cannot obtain enumeration values", e);
	} catch (IllegalAccessException e) {
	throw new IllegalArgumentException("Cannot obtain enumeration values", e);
	} catch (InvocationTargetException e) {
	throw new IllegalArgumentException("Cannot obtain enumeration values", e);
	} catch (NoSuchMethodException e) {
	throw new IllegalArgumentException("Cannot obtain enumeration values", e);
	}
	}

	/** @return true if this is a batch UI that has no user interaction. */
	public abstract boolean isBatch();

	/** Display a header message before a series of prompts. */
	public abstract void header(String fmt, Object... args);

	/** Display a message. */
	public abstract void message(String fmt, Object... args);

	/** Request the user to answer a yes/no question. */
	public abstract boolean yesno(Boolean def, String fmt, Object... args);

	/** Prints a message asking the user to let us know when its safe to continue. */
	public abstract void waitForUser();

	/** Prompt the user for a string, suggesting a default, and returning choice. */
	public abstract String readString(String def, String fmt, Object... args);

	/** Prompt the user to make a choice from an allowed list of values. */
	public abstract String readString(String def, Set<String> allowedValues,
	String fmt, Object... args);

	/** Prompt the user for an integer value, suggesting a default. */
	public int readInt(int def, String fmt, Object... args) {
	for (;;) {
	String p = readString(String.valueOf(def), fmt, args);
	try {
	return Integer.parseInt(p.trim(), 10);
	} catch (NumberFormatException e) {
	System.err.println("error: Invalid integer format: " + p.trim());
	}
	}
	}

	/** Prompt the user for a password, returning the string; null if blank. */
	public abstract String password(String fmt, Object... args);

	/** Prompt the user to make a choice from an enumeration's values. */
	public abstract <T extends Enum<?>> T readEnum(T def, String fmt,
	Object... args);

	private static class Interactive extends ConsoleUI {
	private final Console console;

	Interactive(final Console console) {
	this.console = console;
	}

	@Override
	public boolean isBatch() {
	return false;
	}

	@Override
	public boolean yesno(Boolean def, String fmt, Object... args) {
	final String prompt = String.format(fmt, args);
	for (;;) {
	String y = "y";
	String n = "n";
	if (def != null) {
	if (def) {
	y = "Y";
	} else {
	n = "N";
	}
	}

	String yn = console.readLine("%-30s [%s/%s]? ", prompt, y, n);
	if (yn == null) {
	throw abort();
	}
	yn = yn.trim();
	if (def != null && yn.isEmpty()) {
	return def;
	}
	if (yn.equalsIgnoreCase("y") \|\| yn.equalsIgnoreCase("yes")) {
	return true;
	}
	if (yn.equalsIgnoreCase("n") \|\| yn.equalsIgnoreCase("no")) {
	return false;
	}
	}
	}

	@Override
	public void waitForUser() {
	if (console.readLine("Press enter to continue ") == null) {
	throw abort();
	}
	}

	@Override
	public String readString(String def, String fmt, Object... args) {
	final String prompt = String.format(fmt, args);
	String r;
	if (def != null) {
	r = console.readLine("%-30s [%s]: ", prompt, def);
	} else {
	r = console.readLine("%-30s : ", prompt);
	}
	if (r == null) {
	throw abort();
	}
	r = r.trim();
	if (r.isEmpty()) {
	return def;
	}
	return r;
	}

	@Override
	public String readString(String def, Set<String> allowedValues, String fmt,
	Object... args) {
	for (;;) {
	String r = readString(def, fmt, args);
	if (allowedValues.contains(r.toLowerCase())) {
	return r.toLowerCase();
	}
	if (!"?".equals(r)) {
	console.printf("error: '%s' is not a valid choice\n", r);
	}
	console.printf(" Supported options are:\n");
	for (final String v : allowedValues) {
	console.printf(" %s\n", v.toString().toLowerCase());
	}
	}
	}

	@Override
	public String password(String fmt, Object... args) {
	final String prompt = String.format(fmt, args);
	for (;;) {
	final char[] a1 = console.readPassword("%-30s : ", prompt);
	if (a1 == null) {
	throw abort();
	}

	final char[] a2 = console.readPassword("%30s : ", "confirm password");
	if (a2 == null) {
	throw abort();
	}

	final String s1 = new String(a1);
	final String s2 = new String(a2);
	if (!s1.equals(s2)) {
	console.printf("error: Passwords did not match; try again\n");
	continue;
	}
	return !s1.isEmpty() ? s1 : null;
	}
	}

	@Override
	public <T extends Enum<?>> T readEnum(T def, String fmt, Object... args) {
	final String prompt = String.format(fmt, args);
	final T[] options = all(def);
	for (;;) {
	String r = console.readLine("%-30s [%s/?]: ", prompt, def.toString());
	if (r == null) {
	throw abort();
	}
	r = r.trim();
	if (r.isEmpty()) {
	return def;
	}
	for (final T e : options) {
	if (equalsIgnoreCase(e.toString(), r)) {
	return e;
	}
	}
	if (!"?".equals(r)) {
	console.printf("error: '%s' is not a valid choice\n", r);
	}
	console.printf(" Supported options are:\n");
	for (final T e : options) {
	console.printf(" %s\n", e.toString().toLowerCase());
	}
	}
	}

	@Override
	public void header(String fmt, Object... args) {
	fmt = fmt.replaceAll("\n", "\n*** ");
	console.printf("\n* " + fmt + "\n* \n\n", args);
	}

	@Override
	public void message(String fmt, Object... args) {
	console.printf(fmt, args);
	}
	}

	private static class Batch extends ConsoleUI {
	@Override
	public boolean isBatch() {
	return true;
	}

	@Override
	public boolean yesno(Boolean def, String fmt, Object... args) {
	return def != null ? def : true;
	}

	@Override
	public String readString(String def, String fmt, Object... args) {
	return def;
	}

	@Override
	public String readString(String def, Set<String> allowedValues, String fmt,
	Object... args) {
	return def;
	}

	@Override
	public void waitForUser() {
	}

	@Override
	public String password(String fmt, Object... args) {
	return null;
	}

	@Override
	public <T extends Enum<?>> T readEnum(T def, String fmt, Object... args) {
	return def;
	}

	@Override
	public void header(String fmt, Object... args) {
	}

	@Override
	public void message(String fmt, Object... args) {
	}
	}
	}