net.sf.json.JSONObject 转实体类时日期遇到空“”被赋值一个当前时间的问题

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另见：json 转日期出错，JSONArray.toCollection 时间总是转化为当前时间

net.sf.json 这个包还真是存在不少问题。

上代码：

package net.sf.ezmorph.object;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;

import net.sf.ezmorph.MorphException;

import org.apache.commons.lang.builder.EqualsBuilder;
import org.apache.commons.lang.builder.HashCodeBuilder;

/**
 * Morphs a String to a Date.<br>
 * <p>
 * This morpher will iterate through the supplied formats until one succeeds or
 * the default value is returned (if default value is configured).
 * </p>
 *
 * @author Andres Almiray <[email protected]>
 */
public final class DateMorpherEx extends AbstractObjectMorpher {
	private Date defaultValue;
	private String[] formats;
	private boolean lenient;
	private Locale locale;

	/**
	 * @param formats
	 *            a list of formats this morpher supports.
	 */
	public DateMorpherEx(String[] formats) {
		this(formats, Locale.getDefault(), false);
	}

	/**
	 * @param formats
	 *            a list of formats this morpher supports.
	 * @param lenient
	 *            if the parsing should be lenient or not.
	 */
	public DateMorpherEx(String[] formats, boolean lenient) {
		this(formats, Locale.getDefault(), lenient);
	}

	/**
	 * @param formats
	 *            a list of formats this morpher supports.
	 * @param defaultValue
	 *            return value if the value to be morphed is null.
	 */
	public DateMorpherEx(String[] formats, Date defaultValue) {
		this(formats, defaultValue, Locale.getDefault(), false);
	}

	/**
	 * @param formats
	 *            a list of formats this morpher supports.
	 * @param defaultValue
	 *            return value if the value to be morphed is null.
	 * @param locale
	 *            the Locale used to parse each format.
	 * @param lenient
	 *            if the parsing should be lenient or not.
	 */
	public DateMorpherEx(String[] formats, Date defaultValue, Locale locale, boolean lenient) {
		super(true);
		if (formats == null || formats.length == 0) {
			throw new MorphException("invalid array of formats");
		}
		// should use defensive copying ?
		this.formats = formats;

		if (locale == null) {
			this.locale = Locale.getDefault();
		} else {
			this.locale = locale;
		}

		this.lenient = lenient;
		setDefaultValue(defaultValue);
	}

	/**
	 * @param formats
	 *            a list of formats this morpher supports.
	 * @param locale
	 *            the Locale used to parse each format.
	 */
	public DateMorpherEx(String[] formats, Locale locale) {
		this(formats, locale, false);
	}

	/**
	 * @param formats
	 *            a list of formats this morpher supports.
	 * @param locale
	 *            the Locale used to parse each format.
	 * @param lenient
	 *            if the parsing should be lenient or not.
	 */
	public DateMorpherEx(String[] formats, Locale locale, boolean lenient) {
		if (formats == null || formats.length == 0) {
			throw new MorphException("invalid array of formats");
		}
		// should use defensive copying ?
		this.formats = formats;

		if (locale == null) {
			this.locale = Locale.getDefault();
		} else {
			this.locale = locale;
		}

		this.lenient = lenient;
	}

	public boolean equals(Object obj) {
		if (this == obj) {
			return true;
		}
		if (obj == null) {
			return false;
		}

		if (!(obj instanceof DateMorpherEx)) {
			return false;
		}

		DateMorpherEx other = (DateMorpherEx) obj;
		EqualsBuilder builder = new EqualsBuilder();
		builder.append(formats, other.formats);
		builder.append(locale, other.locale);
		builder.append(lenient, other.lenient);
		if (isUseDefault() && other.isUseDefault()) {
			builder.append(getDefaultValue(), other.getDefaultValue());
			return builder.isEquals();
		} else if (!isUseDefault() && !other.isUseDefault()) {
			return builder.isEquals();
		} else {
			return false;
		}
	}

	/**
	 * Returns the default value for this Morpher.
	 */
	public Date getDefaultValue() {
		if (null != defaultValue){
		return (Date) defaultValue.clone();
		}
		return null;
	}

	public int hashCode() {
		HashCodeBuilder builder = new HashCodeBuilder();
		builder.append(formats);
		builder.append(locale);
		builder.append(lenient);
		if (isUseDefault()) {
			builder.append(getDefaultValue());
		}
		return builder.toHashCode();
	}

	public Object morph(Object value) {
		if (value == null) {
			return null;
		}

		if (Date.class.isAssignableFrom(value.getClass())) {
			return (Date) value;
		}

		if (!supports(value.getClass())) {
			throw new MorphException(value.getClass() + " is not supported");
		}

		String strValue = (String) value;
		strValue = strValue.trim();
		if (0 == strValue.length()){
			if (isUseDefault()) {
				return defaultValue;
			} else {
				throw new MorphException("Unable to parse the date " + value);
			}
		}
		
		SimpleDateFormat dateParser = null;

		for (int i = 0; i < formats.length; i++) {
			if (dateParser == null) {
				dateParser = new SimpleDateFormat(formats[i], locale);
			} else {
				dateParser.applyPattern(formats[i]);
			}
			dateParser.setLenient(lenient);
			try {
				return dateParser.parse(strValue.toLowerCase());
			} catch (ParseException pe) {
				// ignore exception, try the next format
			}
		}

		// unable to parse the date
		if (isUseDefault()) {
			return defaultValue;
		} else {
			throw new MorphException("Unable to parse the date " + value);
		}
	}

	public Class morphsTo() {
		return Date.class;
	}

	/**
	 * Sets the defaultValue to use if the value to be morphed is null.
	 *
	 * @param defaultValue
	 *            return value if the value to be morphed is null
	 */
	public void setDefaultValue(Date defaultValue) {
		if (null != defaultValue) {
			this.defaultValue = (Date) defaultValue.clone();
		}
		this.defaultValue = null;
	}

	public boolean supports(Class clazz) {
		return String.class.isAssignableFrom(clazz);
	}
}

这里面主要是对 setDefaultValue 和 getDefaultValue 进行修改，使其支持 null 值。

还有就是 morph 方法，感觉还有很大的优化空间。