java基础以及操作Excle
今天把会经常用的几个集合的迭代方法又练习了一下，放在这里，经常复习！
map集合迭代
/*** 迭代map【1】*/
for (Integer key : map.keySet()) {//迭代key值 for (String value : map.values()) {//跌打value值 System.out.println("迭代map【1】" + key + ":" + value); } // System.out.println("key\t"+key); }
/*** 迭代map【2】*/
for (Map.Entry<Integer, String> entry : map.entrySet()) {
System.out.println("迭代map【2】" + entry.getKey() + "：" + entry.getValue());
}
/*** 迭代map【3】*/
Iterator<Map.Entry<Integer, String>> entries = map.entrySet().iterator();
while (entries.hasNext()) {
Map.Entry<Integer, String> entry = entries.next();
System.out.println("迭代map【3】" + entry.getKey() + "：" + entry.getValue());
}
List集合迭代
List list = new ArrayList(); list.add("1"); list.add("2"); list.add("3"); list.add("4"); int size = list.size(); System.out.println(size); for(Object li:list){ System.out.println("foreach迭代List集合\t\t"+li); } Iterator iterator = list.iterator(); while (iterator.hasNext()){ System.out.println("Iterator迭代List集合\t\t"+iterator.next()); }
工作需要，经常需要操作本地的Excle,下面总结了一下创建Excle
JAVA EXCEL API:是一开放源码项目，通过它Java开发人员可以读取Excel文件的内容、创建新的Excel文件、更新已经存在的Excel文件。使用该API非Windows操作系统也可以通过纯Java应用来处理Excel数据表。因为它是使用Java编写的，所以我们在Web应用中可以通过JSP、Servlet来调用API实现对Excel数据表的访问。
package yh.com.excle; import jxl.Workbook; import jxl.format.*; import jxl.format.Alignment; import jxl.write.*; import jxl.write.Colour; import jxl.write.biff.RowsExceededException; import java.io.File; import java.io.IOException; /** * Created by vincce on 2015/11/9. */ public class WriteMsgToExcle { private static final String filePath = "E:\\study\\test\\createExcle.xls"; public static void main(String[] args) { createExcle(); } /** * 创建Excle到本地 */ public static void createExcle(){ try { WritableWorkbook writableWorkbook = Workbook.createWorkbook(new File(filePath));//在指定目录下创建Excl WritableSheet sheet = writableWorkbook.createSheet("myFirst", 0);//创建一个sheet ，参数含义分别是 sheet名字 该Excle文件中第一个sheet sheet.setRowView(0, 600, false);//设置第一行的高度 WritableCellFormat writableCellFormat = new WritableCellFormat(); writableCellFormat.setBackground(Colour.GRAY_25);//设置背景色 writableCellFormat.setAlignment(Alignment.CENTRE);//设置居中显示 WritableFont color = new WritableFont(WritableFont.ARIAL);//选择字体 color.setColour(Colour.GOLD);//设置字体颜色为金黄色 WritableCellFormat colorFormat = new WritableCellFormat(color); //第一行 // Label l1 = new Label(0,0,"name",colorFormat);//创建单元格 参数含义分别是 列坐标，行坐标 内容,字体颜色 Label l1 = new Label(0,0,"name",writableCellFormat);//创建单元格 参数含义分别是 列坐标，行坐标 内容，背景色 sheet.addCell(l1); // Label l2 = new Label(1,0,"sex",colorFormat); Label l2 = new Label(1,0,"sex",writableCellFormat); sheet.addCell(l2); // Label l3 = new Label(2,0,"age",colorFormat); Label l3 = new Label(2,0,"age",writableCellFormat); sheet.addCell(l3); // Label l4 = new Label(3,0,"score",colorFormat); Label l4 = new Label(3,0,"score",writableCellFormat); sheet.addCell(l4); //第二行 Label l5 = new Label(0,1,"john"); sheet.addCell(l5); Label l6 = new Label(1,1,"male"); sheet.addCell(l6); Label l7 = new Label(2,1,"20"); sheet.addCell(l7); Label l8 = new Label(3,1,"100"); sheet.addCell(l8); //将创建的内容写入到输出流，并关闭输出流 writableWorkbook.write(); writableWorkbook.close(); } catch (IOException e) { e.printStackTrace(); } catch (RowsExceededException e) { e.printStackTrace(); } catch (WriteException e) { e.printStackTrace(); } } }
需要依赖
<dependency>
<groupId>net.sourceforge.jexcelapi</groupId>
<artifactId>jxl</artifactId>
<version>2.6.10</version>
</dependency>
读取Excle中的某一列
public static void test2(String path){ File file = new File(path); Workbook workbook; try { workbook = Workbook.getWorkbook(file); Sheet sheet = workbook.getSheet(0);//获取第一个sheet Cell[] cell = sheet.getColumn(4);//获取第一列中的值 int len = cell.length;//共有多少行 Map<Integer,String> map = new HashMap(); for(int i = 0;i<len;i++){ Cell cell1 = cell[i]; System.out.println("第"+(i+Integer.parseInt("1"))+"行\t"+cell1.getContents()+"\t"+"'"+cell1.getContents()+"',"); map.put(i,cell1.getContents()); // System.out.println("select * from axa_user where id="+"'"+cell1.getContents()+"',"); } System.out.println("总共有"+len+"行"); System.out.println(map.toString()); /* Sheet sheet1 = workbook.getSheet(1);//读取第二个sheet中的内容 Cell[] cell1 = sheet1.getColumn(0);//获取第一列中内容 Cell[] cell2 = sheet1.getColumn(1);//获取第二列中内容 Map<Integer,String> map1 = new HashMap<Integer, String>(); for(int len1=0;len1<cell1.length;len1++){ Cell c1 = cell1[len1]; map1.put(len1,c1.getContents()); } Map<Integer,String> map2 = new HashMap<Integer, String>(); for(int len2=0;len2<cell2.length;len2++){ Cell c2 = cell2[len2]; map2.put(len2,c2.getContents()); } Map<Integer,String> map3 = new HashMap<Integer, String>(); for(Map.Entry<Integer,String> entry2:map2.entrySet()){ for(Map.Entry<Integer,String> entry1:map1.entrySet()){ if(entry2.getValue().equals(entry1.getValue())){ map3.put(entry1.getKey(),entry1.getValue()); } } } System.out.println(cell1.length); System.out.println(cell2.length); System.out.println("map1\t"+map1.toString()); System.out.println("map2\t"+map2.toString()); System.out.println("map3\t"+map3.toString()); */ } catch (IOException e) { e.printStackTrace(); } catch (BiffException e) { e.printStackTrace(); } }
