datetickunit.html

jfreechart1。0。2的api。

<FONT color="green">147</FONT>            this.rollCount = rollCount;<a name="line.147"></a>
<FONT color="green">148</FONT>            this.formatter = formatter;<a name="line.148"></a>
<FONT color="green">149</FONT>            if (formatter == null) {<a name="line.149"></a>
<FONT color="green">150</FONT>                this.formatter = DateFormat.getDateInstance(DateFormat.SHORT);<a name="line.150"></a>
<FONT color="green">151</FONT>            }<a name="line.151"></a>
<FONT color="green">152</FONT>        }<a name="line.152"></a>
<FONT color="green">153</FONT>    <a name="line.153"></a>
<FONT color="green">154</FONT>        /**<a name="line.154"></a>
<FONT color="green">155</FONT>         * Returns the date unit.  This will be one of the constants <a name="line.155"></a>
<FONT color="green">156</FONT>         * &lt;code&gt;YEAR&lt;/code&gt;, &lt;code&gt;MONTH&lt;/code&gt;, &lt;code&gt;DAY&lt;/code&gt;, <a name="line.156"></a>
<FONT color="green">157</FONT>         * &lt;code&gt;HOUR&lt;/code&gt;, &lt;code&gt;MINUTE&lt;/code&gt;, &lt;code&gt;SECOND&lt;/code&gt; or <a name="line.157"></a>
<FONT color="green">158</FONT>         * &lt;code&gt;MILLISECOND&lt;/code&gt;, defined by this class.  Note that these <a name="line.158"></a>
<FONT color="green">159</FONT>         * constants do NOT correspond to those defined in Java's <a name="line.159"></a>
<FONT color="green">160</FONT>         * &lt;code&gt;Calendar&lt;/code&gt; class.<a name="line.160"></a>
<FONT color="green">161</FONT>         *<a name="line.161"></a>
<FONT color="green">162</FONT>         * @return The date unit.<a name="line.162"></a>
<FONT color="green">163</FONT>         */<a name="line.163"></a>
<FONT color="green">164</FONT>        public int getUnit() {<a name="line.164"></a>
<FONT color="green">165</FONT>            return this.unit;<a name="line.165"></a>
<FONT color="green">166</FONT>        }<a name="line.166"></a>
<FONT color="green">167</FONT>    <a name="line.167"></a>
<FONT color="green">168</FONT>        /**<a name="line.168"></a>
<FONT color="green">169</FONT>         * Returns the unit count.<a name="line.169"></a>
<FONT color="green">170</FONT>         *<a name="line.170"></a>
<FONT color="green">171</FONT>         * @return The unit count.<a name="line.171"></a>
<FONT color="green">172</FONT>         */<a name="line.172"></a>
<FONT color="green">173</FONT>        public int getCount() {<a name="line.173"></a>
<FONT color="green">174</FONT>            return this.count;<a name="line.174"></a>
<FONT color="green">175</FONT>        }<a name="line.175"></a>
<FONT color="green">176</FONT>    <a name="line.176"></a>
<FONT color="green">177</FONT>        /**<a name="line.177"></a>
<FONT color="green">178</FONT>         * Returns the roll unit.  This is the amount by which the tick advances if<a name="line.178"></a>
<FONT color="green">179</FONT>         * it is "hidden" when displayed on a segmented date axis.  Typically the <a name="line.179"></a>
<FONT color="green">180</FONT>         * roll will be smaller than the regular tick unit (for example, a 7 day <a name="line.180"></a>
<FONT color="green">181</FONT>         * tick unit might use a 1 day roll).<a name="line.181"></a>
<FONT color="green">182</FONT>         *<a name="line.182"></a>
<FONT color="green">183</FONT>         * @return The roll unit.<a name="line.183"></a>
<FONT color="green">184</FONT>         */<a name="line.184"></a>
<FONT color="green">185</FONT>        public int getRollUnit() {<a name="line.185"></a>
<FONT color="green">186</FONT>            return this.rollUnit;<a name="line.186"></a>
<FONT color="green">187</FONT>        }<a name="line.187"></a>
<FONT color="green">188</FONT>    <a name="line.188"></a>
<FONT color="green">189</FONT>        /**<a name="line.189"></a>
<FONT color="green">190</FONT>         * Returns the roll count.<a name="line.190"></a>
<FONT color="green">191</FONT>         *<a name="line.191"></a>
<FONT color="green">192</FONT>         * @return The roll count.<a name="line.192"></a>
<FONT color="green">193</FONT>         */<a name="line.193"></a>
<FONT color="green">194</FONT>        public int getRollCount() {<a name="line.194"></a>
<FONT color="green">195</FONT>            return this.rollCount;<a name="line.195"></a>
<FONT color="green">196</FONT>        }<a name="line.196"></a>
<FONT color="green">197</FONT>    <a name="line.197"></a>
<FONT color="green">198</FONT>        /**<a name="line.198"></a>
<FONT color="green">199</FONT>         * Formats a value.<a name="line.199"></a>
<FONT color="green">200</FONT>         *<a name="line.200"></a>
<FONT color="green">201</FONT>         * @param milliseconds  date in milliseconds since 01-01-1970.<a name="line.201"></a>
<FONT color="green">202</FONT>         *<a name="line.202"></a>
<FONT color="green">203</FONT>         * @return The formatted date.<a name="line.203"></a>
<FONT color="green">204</FONT>         */<a name="line.204"></a>
<FONT color="green">205</FONT>        public String valueToString(double milliseconds) {<a name="line.205"></a>
<FONT color="green">206</FONT>            return this.formatter.format(new Date((long) milliseconds));<a name="line.206"></a>
<FONT color="green">207</FONT>        }<a name="line.207"></a>
<FONT color="green">208</FONT>    <a name="line.208"></a>
<FONT color="green">209</FONT>        /**<a name="line.209"></a>
<FONT color="green">210</FONT>         * Formats a date using the tick unit's formatter.<a name="line.210"></a>
<FONT color="green">211</FONT>         *<a name="line.211"></a>
<FONT color="green">212</FONT>         * @param date  the date.<a name="line.212"></a>
<FONT color="green">213</FONT>         *<a name="line.213"></a>
<FONT color="green">214</FONT>         * @return The formatted date.<a name="line.214"></a>
<FONT color="green">215</FONT>         */<a name="line.215"></a>
<FONT color="green">216</FONT>        public String dateToString(Date date) {<a name="line.216"></a>
<FONT color="green">217</FONT>            return this.formatter.format(date);<a name="line.217"></a>
<FONT color="green">218</FONT>        }<a name="line.218"></a>
<FONT color="green">219</FONT>    <a name="line.219"></a>
<FONT color="green">220</FONT>        /**<a name="line.220"></a>
<FONT color="green">221</FONT>         * Calculates a new date by adding this unit to the base date.<a name="line.221"></a>
<FONT color="green">222</FONT>         *<a name="line.222"></a>
<FONT color="green">223</FONT>         * @param base  the base date.<a name="line.223"></a>
<FONT color="green">224</FONT>         *<a name="line.224"></a>
<FONT color="green">225</FONT>         * @return A new date one unit after the base date.<a name="line.225"></a>
<FONT color="green">226</FONT>         */<a name="line.226"></a>
<FONT color="green">227</FONT>        public Date addToDate(Date base) {<a name="line.227"></a>
<FONT color="green">228</FONT>    <a name="line.228"></a>
<FONT color="green">229</FONT>            Calendar calendar = Calendar.getInstance();<a name="line.229"></a>
<FONT color="green">230</FONT>            calendar.setTime(base);<a name="line.230"></a>
<FONT color="green">231</FONT>            calendar.add(getCalendarField(this.unit), this.count);<a name="line.231"></a>
<FONT color="green">232</FONT>            return calendar.getTime();<a name="line.232"></a>
<FONT color="green">233</FONT>    <a name="line.233"></a>
<FONT color="green">234</FONT>        }<a name="line.234"></a>
<FONT color="green">235</FONT>    <a name="line.235"></a>
<FONT color="green">236</FONT>        /**<a name="line.236"></a>
<FONT color="green">237</FONT>         * Rolls the date forward by the amount specified by the roll unit and <a name="line.237"></a>
<FONT color="green">238</FONT>         * count.<a name="line.238"></a>
<FONT color="green">239</FONT>         *<a name="line.239"></a>
<FONT color="green">240</FONT>         * @param base  the base date.<a name="line.240"></a>
<FONT color="green">241</FONT>    <a name="line.241"></a>
<FONT color="green">242</FONT>         * @return The rolled date.<a name="line.242"></a>
<FONT color="green">243</FONT>         */<a name="line.243"></a>
<FONT color="green">244</FONT>        public Date rollDate(Date base) {<a name="line.244"></a>
<FONT color="green">245</FONT>            Calendar calendar = Calendar.getInstance();<a name="line.245"></a>
<FONT color="green">246</FONT>            calendar.setTime(base);<a name="line.246"></a>
<FONT color="green">247</FONT>            calendar.add(getCalendarField(this.rollUnit), this.rollCount);<a name="line.247"></a>
<FONT color="green">248</FONT>            return calendar.getTime();<a name="line.248"></a>
<FONT color="green">249</FONT>        }<a name="line.249"></a>
<FONT color="green">250</FONT>    <a name="line.250"></a>
<FONT color="green">251</FONT>        /**<a name="line.251"></a>
<FONT color="green">252</FONT>         * Returns a field code that can be used with the &lt;code&gt;Calendar&lt;/code&gt; <a name="line.252"></a>
<FONT color="green">253</FONT>         * class.<a name="line.253"></a>
<FONT color="green">254</FONT>         *<a name="line.254"></a>
<FONT color="green">255</FONT>         * @return The field code.<a name="line.255"></a>
<FONT color="green">256</FONT>         */<a name="line.256"></a>
<FONT color="green">257</FONT>        public int getCalendarField() {<a name="line.257"></a>
<FONT color="green">258</FONT>            return getCalendarField(this.unit);<a name="line.258"></a>
<FONT color="green">259</FONT>        }<a name="line.259"></a>
<FONT color="green">260</FONT>    <a name="line.260"></a>
<FONT color="green">261</FONT>        /**<a name="line.261"></a>
<FONT color="green">262</FONT>         * Returns a field code (that can be used with the Calendar class) for a <a name="line.262"></a>
<FONT color="green">263</FONT>         * given 'unit' code.  The 'unit' is one of:  {@link #YEAR}, {@link #MONTH},<a name="line.263"></a>
<FONT color="green">264</FONT>         * {@link #DAY}, {@link #HOUR}, {@link #MINUTE}, {@link #SECOND} and <a name="line.264"></a>
<FONT color="green">265</FONT>         * {@link #MILLISECOND}.<a name="line.265"></a>
<FONT color="green">266</FONT>         *<a name="line.266"></a>
<FONT color="green">267</FONT>         * @param tickUnit  the unit.<a name="line.267"></a>
<FONT color="green">268</FONT>         *<a name="line.268"></a>
<FONT color="green">269</FONT>         * @return The field code.<a name="line.269"></a>
<FONT color="green">270</FONT>         */<a name="line.270"></a>
<FONT color="green">271</FONT>        private int getCalendarField(int tickUnit) {<a name="line.271"></a>
<FONT color="green">272</FONT>    <a name="line.272"></a>
<FONT color="green">273</FONT>            switch (tickUnit) {<a name="line.273"></a>
<FONT color="green">274</FONT>                case (YEAR):<a name="line.274"></a>
<FONT color="green">275</FONT>                    return Calendar.YEAR;<a name="line.275"></a>
<FONT color="green">276</FONT>                case (MONTH):<a name="line.276"></a>
<FONT color="green">277</FONT>                    return Calendar.MONTH;<a name="line.277"></a>
<FONT color="green">278</FONT>                case (DAY):<a name="line.278"></a>
<FONT color="green">279</FONT>                    return Calendar.DATE;<a name="line.279"></a>
<FONT color="green">280</FONT>                case (HOUR):<a name="line.280"></a>
<FONT color="green">281</FONT>                    return Calendar.HOUR_OF_DAY;<a name="line.281"></a>
<FONT color="green">282</FONT>                case (MINUTE):<a name="line.282"></a>
<FONT color="green">283</FONT>                    return Calendar.MINUTE;<a name="line.283"></a>
<FONT color="green">284</FONT>                case (SECOND):<a name="line.284"></a>
<FONT color="green">285</FONT>                    return Calendar.SECOND;<a name="line.285"></a>
<FONT color="green">286</FONT>                case (MILLISECOND):<a name="line.286"></a>
<FONT color="green">287</FONT>                    return Calendar.MILLISECOND;<a name="line.287"></a>
<FONT color="green">288</FONT>                default:<a name="line.288"></a>
<FONT color="green">289</FONT>                    return Calendar.MILLISECOND;<a name="line.289"></a>
<FONT color="green">290</FONT>            }<a name="line.290"></a>
<FONT color="green">291</FONT>    <a name="line.291"></a>
<FONT color="green">292</FONT>        }<a name="line.292"></a>
<FONT color="green">293</FONT>    <a name="line.293"></a>
<FONT color="green">294</FONT>        /**<a name="line.294"></a>
<FONT color="green">295</FONT>         * Returns the (approximate) number of milliseconds for the given unit and <a name="line.295"></a>