stringflags.java

Jodd是一个开源的公用Java基础类库

package jodd.util;

import java.util.HashMap;
import java.util.Iterator;

import jodd.bean.BeanUtil;

/**
 * Parses string and sets bean boolean parameters (flags) depending on
 * exisiting characters. Class may be used when methods has many boolean
 * parameters. In this cases, a single string can replace all those
 * parameters, where chars represent if some boolean property should be
 * set to <code>true</code> or <code>false</code>.
 * <p>
 *
 * Usually, this class is instanced and configured in static block of a
 * class that uses it:<br>
 * <code>
 * private static StringFlags flags = new StringFlags();
 * static {
 *     flags.addFlag('p', "fooP", true);
 *     flags.addFlag('d', "fooD", false);
 * }
 * </code>
 *
 * Flags boolean values are those that properties will be set to if
 * coresponding character exist in option string. This means that when such
 * character doesn't exist in options string, its parameter will be set to
 * inverse value. In above example, if option string contains char 'p' then
 * setFooP(true) will be performed, otherwise setFooP(false) will be
 * performed. For the 'd' flag is opposite: if it is present in the option
 * string, setFooD(false) will be executed, otherwise setFooD(true) will be
 * executed.
 */
public class StringFlags {

	private HashMap map = new HashMap();

	class Flag {
		String bpname;
		boolean val;
	}

	/**
	 * Add new flag to the buffer.
	 *
	 * @param c      character flag
	 * @param bpname name of bean property (without set or get)
	 * @param val    value that will be set if character exist in the string.
	 */
	public void addFlag(char c, String bpname, boolean val) {
		Flag f = new Flag();
		f.bpname = bpname;
		f.val = val;
		map.put(new Character(c), f);
	}

	/**
	 * Clears complete flags buffer.
	 */
	public void clearFlags() {
		map.clear();
	}


	/**
	 * Parses given string and sets the boolean properties of a bean.
	 *
	 * @param params option string, contains char flags
	 * @param o      object to populate
	 */
	public void parse(String params, Object o) {
		if (params == null) {
			params = "";
		}
		char[] ca = params.toCharArray();
		Iterator i = map.keySet().iterator();
		while (i.hasNext()) {
			Character c = (Character) i.next();
			Flag f = (Flag) map.get(c);
			if (f == null) {
				continue;
			}
			boolean b = f.val;
			if (params.indexOf(c.charValue()) == -1) {
				b = !b;
			}
			BeanUtil.setProperty(o, f.bpname, new Boolean(b));
		}
	}

}