Java2d画直角坐标系

最近项目用到java作图，首先想到的是利用开源插件jfreechart，文档收费，网上资料参差不齐，最后还是觉得采用java2D bufferedImage作图。 现在分享一下。

把一张图片分为border部分和主体部分，如下图所示：

定义一个边界类

/**
 * Copyright (c) 2014, alax
 * All Rights Reserved.
 */

package chapterOne.axis;
/**
 *
 * @author   	 alax_app@yeah.net
 * @Date	 	 2014-3-18 下午11:41:10
 *
 */
public class AxisBorder {
	
	private int left;
	private int right;
	private int top;
	private int bottom;
	
	private int backgroundColor;	//背景色
	
	public AxisBorder(){
		
	}
	
	public AxisBorder(int left, int right, int top, int bottom,
			int backgroundColor) {
		super();
		this.left = left;
		this.right = right;
		this.top = top;
		this.bottom = bottom;
		this.backgroundColor = backgroundColor;
	}



	public int getLeft() {
		return left;
	}

	public void setLeft(int left) {
		this.left = left;
	}

	public int getRight() {
		return right;
	}

	public void setRight(int right) {
		this.right = right;
	}

	public int getTop() {
		return top;
	}

	public void setTop(int top) {
		this.top = top;
	}

	public int getBottom() {
		return bottom;
	}

	public void setBottom(int bottom) {
		this.bottom = bottom;
	}

	public int getBackgroundColor() {
		return backgroundColor;
	}

	public void setBackgroundColor(int backgroundColor) {
		this.backgroundColor = backgroundColor;
	}
	
}

接下来定义坐标轴实例

/**
 * Copyright (c) 2014, alax
 * All Rights Reserved.
 */

package chapterOne.axis;

import java.util.Date;

/**
 *
 * @author   	 alax_app@yeah.net
 * @Date	 	 2014-3-19 上午12:10:01
 *
 */
public class Axis {
	public static final String VALUE = "value";
	public static final String DATETIME = "datetime";
	
	private int lineColor;		//y轴颜色
	private int lineWidth;		//y轴宽度
	private String title;		//y轴标题
	private String type;		//y轴类型  支持value 类型 和datetime类型
	
	private double max;			//最大值
	private double min;			//最小值
	
	private int ticks;			//刻度个数
	
	private Date startDate;
	private Date endDate;
	
	
	private String labelFormat; //刻度值排版 
	
	
	public Axis(){
		
	}
	


	public Axis(int lineColor, int lineWidth, String title, String type,
			double max, double min, int ticks, Date startDate, Date endDate,
			String labelFormat) {
		super();
		this.lineColor = lineColor;
		this.lineWidth = lineWidth;
		this.title = title;
		this.type = type;
		this.max = max;
		this.min = min;
		this.ticks = ticks;
		this.startDate = startDate;
		this.endDate = endDate;
		this.labelFormat = labelFormat;
	}






	public int getLineColor() {
		return lineColor;
	}

	public void setLineColor(int lineColor) {
		this.lineColor = lineColor;
	}

	public int getLineWidth() {
		return lineWidth;
	}

	public void setLineWidth(int lineWidth) {
		this.lineWidth = lineWidth;
	}

	public String getTitle() {
		return title;
	}

	public void setTitle(String title) {
		this.title = title;
	}

	public String getType() {
		return type;
	}

	public void setType(String type) {
		this.type = type;
	}

	public double getMax() {
		return max;
	}

	public void setMax(double max) {
		this.max = max;
	}

	public double getMin() {
		return min;
	}

	public void setMin(double min) {
		this.min = min;
	}


	public String getLabelFormat() {
		return labelFormat;
	}

	public void setLabelFormat(String labelFormat) {
		this.labelFormat = labelFormat;
	}


	public Date getStartDate() {
		return startDate;
	}


	public void setStartDate(Date startDate) {
		this.startDate = startDate;
	}


	public Date getEndDate() {
		return endDate;
	}

	public void setEndDate(Date endDate) {
		this.endDate = endDate;
	}


	public int getTicks() {
		return ticks;
	}


	public void setTicks(int ticks) {
		this.ticks = ticks;
	}
	
	
}

定义点

/**
 * Copyright (c) 2014, alax
 * All Rights Reserved.
 */

package chapterOne.axis;
/**
 *
 * @author   	 alax_app@yeah.net
 * @Date	 	 2014-3-19 上午12:35:20
 *
 */
public class Point {
	
	private int x;
	private int y;
	
	
	public Point(int x, int y) {
		super();
		this.x = x;
		this.y = y;
	}
	public int getX() {
		return x;
	}
	public void setX(int x) {
		this.x = x;
	}
	public int getY() {
		return y;
	}
	public void setY(int y) {
		this.y = y;
	}
	
}

画利用bufferedImage画坐标

/**
 * Copyright (c) 2014, alax
 * All Rights Reserved.
 */

package chapterOne.axis;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.image.BufferedImage;
import java.io.File;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

import javax.imageio.ImageIO;

/**
 *
 * @author   	 alax_app@yeah.net
 * @Date	 	 2014-3-19 上午12:30:20
 *
 */
public class AxisUtils {

	
	public static void main(String[] args) throws Exception {
		int width = 1000;
		int height = 400;
		AxisBorder axisBorder = new AxisBorder(60, 60, 40, 40, 0xffffff);
		BufferedImage bufferedImage = new BufferedImage(width+axisBorder.getLeft() + axisBorder.getRight(),
				height + axisBorder.getTop() +axisBorder.getBottom(), BufferedImage.TYPE_INT_RGB);
		SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
		
		Graphics2D g = bufferedImage.createGraphics();
		Date startDate = sdf.parse("20140318120000");
		Date endDate = sdf.parse("20140320120000");
		Axis xAxis = new Axis(0x000000, 2, "时间", "datetime", 0, 0, 5, startDate, endDate, "");
		Axis yAxis = new Axis(0x000000, 2, "高度", "value", 30, 0, 5, null, null, "");
		drawAxis(axisBorder, xAxis, yAxis, width, height, g);
		
		//导出图片
		String pathname = "E:\\config\\test.jpg";
		ImageIO.write(bufferedImage, "jpg", new File(pathname));
		
	}
	public static void drawAxis(AxisBorder border ,Axis xaxis, Axis yaxis, int width, int height, Graphics2D g){
		//抗锯齿 字体更平滑
		g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
		drawBorder(border, width, height, g);
		drawXAxis(border, xaxis, width, height, g);
		drawYAxis(border, yaxis, width, height, g);
		//设置作图区域颜色为白色
		g.setColor(new Color(0xFFFFFF));
		g.fillRect(border.getLeft(), border.getTop(), width, height);
	}
	
	/**
	 * 画x轴坐标
	 * @param axisBorder
	 * @param xaxis
	 * @param width
	 * @param height
	 * @param g
	 */
	private static void drawXAxis(AxisBorder axisBorder,
			Axis xaxis, int width ,int height, Graphics2D g){
		//画x坐标
		Point point1 = new Point(axisBorder.getLeft(), axisBorder.getTop() + height);
		Point point2 = new Point(axisBorder.getLeft() + width, axisBorder.getTop() + height);
		drawLine(point1, point2, new Color(xaxis.getLineColor()) , xaxis.getLineWidth(), g);
		//画刻度
		int ticks = xaxis.getTicks();
		int skips = width / ticks;
		int x = axisBorder.getLeft();
		int y1 = axisBorder.getTop() + height ;
		int y2 = y1 + 10;
		String type = xaxis.getType();	//获取坐标轴类型
		for(int i = 1 ; i <= ticks ; i++){
			point1 = new Point(x + skips * i,y1);
			point2 = new Point(x + skips * i,y2);
			drawLine(point1, point2, new Color(xaxis.getLineColor()) , xaxis.getLineWidth(), g);
			
		}
		//画label
		if(type.equals(Axis.VALUE)){
			double vskips = (xaxis.getMax() - xaxis.getMin() ) / ticks + xaxis.getMin();
			for(int i = 1 ; i <= ticks ; i++){
				drawString(g, x + skips * i, y2, getValueLabel(vskips * i + xaxis.getMin(), xaxis.getLabelFormat()));
			}
		}else if(type.equals(Axis.DATETIME)){
			long t0 = xaxis.getStartDate().getTime() ;
			long tskips = ( xaxis.getEndDate().getTime() - t0 ) /ticks;
			Calendar c = Calendar.getInstance();
			for(int i = 1 ; i <= ticks ; i++){
				c.setTimeInMillis(t0 + i * tskips);
				drawString(g, x + skips * i, y2+10, getDateLabel(c.getTime(), xaxis.getLabelFormat()));
			}
		}
		//画title
		drawString(g, axisBorder.getLeft(), 
				axisBorder.getTop() + height + axisBorder.getBottom() /2, xaxis.getTitle());
		
	}
	
	
	/**
	 * 画Y轴坐标
	 * @param axisBorder
	 * @param yaxis
	 * @param width
	 * @param height
	 * @param g
	 */
	private static void drawYAxis(AxisBorder axisBorder,
			Axis axis, int width ,int height, Graphics2D g){
		//画x坐标
		Point point1 = new Point(axisBorder.getLeft(), axisBorder.getTop() + height);
		Point point2 = new Point(axisBorder.getLeft(), axisBorder.getTop());
		
		
		drawLine(point1, point2, new Color(axis.getLineColor()) , axis.getLineWidth(), g);
		
		//画刻度
		int ticks = axis.getTicks();
		int skips = height / ticks;
		int x1 = axisBorder.getLeft();
		int x2 = x1 - 10 ;
		int y1 = axisBorder.getTop() + height ;
		String type = axis.getType();	//获取坐标轴类型
		for(int i = 1 ; i <= ticks ; i++){
			point1 = new Point(x2,y1 - skips * i);
			point2 = new Point(x1,y1 - skips * i);
			drawLine(point1, point2, new Color(axis.getLineColor()) , axis.getLineWidth(), g);
			
		}
		//画label
		if(type.equals(Axis.VALUE)){
			double vskips = (axis.getMax() - axis.getMin() ) / ticks + axis.getMin();
			for(int i = 1 ; i <= ticks ; i++){
				drawString(g, x2 - 20 , y1 - skips * i, getValueLabel(vskips * i + axis.getMin(), axis.getLabelFormat()));
			}
		}else if(type.equals(Axis.DATETIME)){
			long t0 = axis.getStartDate().getTime() ;
			long tskips = ( axis.getEndDate().getTime() - t0 ) /ticks;
			Calendar c = Calendar.getInstance();
			for(int i = 1 ; i <= ticks ; i++){
				c.setTimeInMillis(t0 + i * tskips);
				drawString(g, x2 - 20 , y1 - skips * i, getDateLabel(c.getTime(), axis.getLabelFormat()));
			}
		}
		//画title
		//画y坐标title
		int x = Math.min(30, axisBorder.getLeft());
		int y0 = axisBorder.getTop() + height/2 + 80;
		
		//逆时针旋转180度
		g.rotate(-Math.PI/2, x, y0);
		Font font = new Font("宋体", Font.BOLD, 16);
		g.setFont(font);
		g.drawString(axis.getTitle(),x,y0);
		//恢复画布，顺时针旋转180度
		g.rotate(Math.PI/2,x,y0);
		
	}
	
	/**
	 * 画线
	 * @param point1
	 * @param point2
	 * @param lineColor
	 * @param lineWidth
	 * @param g
	 */
	private static void drawLine(Point point1 , Point point2, Color lineColor, int lineWidth ,Graphics2D g){
		g.setStroke(new BasicStroke(lineWidth));
		g.setColor(lineColor);
		g.drawLine(point1.getX(), point1.getY(), point2.getX(), point2.getY());
	}
	
	/**
	 * 写字符
	 */
	private static void drawString(Graphics2D g,int x ,int y,String str){
		g.drawString(str, x, y);
	}
	
	
	
	/**
	 * 获取数字型label
	 * @param value
	 * @param format
	 * @return
	 */
	public static String getValueLabel(double value , String format ){
		if(format == null  || format.equals("")){
			return value +"";
		}
		return String.format(format, value+"");
	}
	
	/**
	 * 获取时间类型label
	 * @param date
	 * @param format
	 * @return
	 */
	public static String getDateLabel(Date date , String format){
		SimpleDateFormat sdf = new SimpleDateFormat("dd");
		if(format == null  || format.equals("")){
			format = "dd日HH时";
		}
		sdf.applyPattern(format);
		return sdf.format(date);
	}
	
	/**
	 * 画border
	 * @param border
	 * @param width
	 * @param height
	 * @param g
	 */
	public static void drawBorder(AxisBorder border, int width, int height,Graphics2D g){
		g.setColor(new Color(border.getBackgroundColor()));
		g.fillRect(0, 0, border.getLeft(), border.getTop()+height+border.getBottom()); //填充背景色
		g.fillRect(border.getLeft(), 0, width+border.getRight(), border.getTop());
		g.fillRect(border.getLeft(), border.getTop()+height, width+border.getRight(), border.getBottom());
		g.fillRect(border.getLeft()+width, border.getTop(), border.getRight(), height);
	}
	
}

测试方法

public static void main(String[] args) throws Exception {
		int width = 1000;
		int height = 400;
		AxisBorder axisBorder = new AxisBorder(60, 60, 40, 40, 0xffffff);
		BufferedImage bufferedImage = new BufferedImage(width+axisBorder.getLeft() + axisBorder.getRight(),
				height + axisBorder.getTop() +axisBorder.getBottom(), BufferedImage.TYPE_INT_RGB);
		SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
		
		Graphics2D g = bufferedImage.createGraphics();
		Date startDate = sdf.parse("20140318120000");
		Date endDate = sdf.parse("20140320120000");
		Axis xAxis = new Axis(0x000000, 2, "时间", "datetime", 0, 0, 5, startDate, endDate, "");
		Axis yAxis = new Axis(0x000000, 2, "高度", "value", 30, 0, 5, null, null, "");
		drawAxis(axisBorder, xAxis, yAxis, width, height, g);
		
		//导出图片
		String pathname = "E:\\config\\test.jpg";
		ImageIO.write(bufferedImage, "jpg", new File(pathname));
		
	}

最终效果图如下