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最新评论
-
hui1989106a:
我的也不能解压,360和好压都试了,都不行
《Spring in Action》完整中文版分享下载 -
temotemo:
这些example有些过时了,官方建议使用HBase-1.0 ...
Java操作Hbase进行建表、删表以及对数据进行增删改查,条件查询 -
zy8102:
非常感谢~
HeadFirst系列之七:《深入浅出SQL》原版高清PDF电子书分享下载 -
zy8102:
重命名了一下搞定了
HeadFirst系列之七:《深入浅出SQL》原版高清PDF电子书分享下载 -
zy8102:
为什么下载以后老解压不了呢?
HeadFirst系列之七:《深入浅出SQL》原版高清PDF电子书分享下载
其一:CSV文件读取与生成
①CSV文件读取
读取操作类:
public class CSVReader {
private BufferedReader br;
private boolean hasNext = true;
private char separator;//分隔符
private char quotechar;//引号符
private int skipLines;//
private boolean linesSkiped; //转移线
/** The default separator to use if none is supplied to the constructor. */
public static final char DEFAULT_SEPARATOR = ',';
/**
* The default quote character to use if none is supplied to the
* constructor.
*/
public static final char DEFAULT_QUOTE_CHARACTER = '"';
/**
* The default line to start reading.
*/
public static final int DEFAULT_SKIP_LINES = 0;
/**
* Constructs CSVReader using a comma for the separator.
*
* @param reader
* the reader to an underlying CSV source.
*/
public CSVReader(Reader reader) {
this(reader, DEFAULT_SEPARATOR);
}
/**
* Constructs CSVReader with supplied separator.
*
* @param reader
* the reader to an underlying CSV source.
* @param separator
* the delimiter to use for separating entries.
*/
public CSVReader(Reader reader, char separator) {
this(reader, separator, DEFAULT_QUOTE_CHARACTER);
}
/**
* Constructs CSVReader with supplied separator and quote char.
*
* @param reader
* the reader to an underlying CSV source.
* @param separator
* the delimiter to use for separating entries
* @param quotechar
* the character to use for quoted elements
*/
public CSVReader(Reader reader, char separator, char quotechar) {
this(reader, separator, quotechar, DEFAULT_SKIP_LINES);
}
/**
* Constructs CSVReader with supplied separator and quote char.
*
* @param reader
* the reader to an underlying CSV source.
* @param separator
* the delimiter to use for separating entries
* @param quotechar
* the character to use for quoted elements
* @param line
* the line number to skip for start reading
*/
public CSVReader(Reader reader, char separator, char quotechar, int line) {
this.br = new BufferedReader(reader);
this.separator = separator;
this.quotechar = quotechar;
this.skipLines = line;
}
/**
* Reads the entire file into a List with each element being a String[] of
* tokens.
*
* @return a List of String[], with each String[] representing a line of the
* file.
*
* @throws IOException
* if bad things happen during the read
*/
public List readAll() throws IOException {
List allElements = new ArrayList();
while (hasNext) {
String[] nextLineAsTokens = readNext();
if (nextLineAsTokens != null)
allElements.add(nextLineAsTokens);
}
return allElements;
}
/**
* Reads the next line from the buffer and converts to a string array.
*
* @return a string array with each comma-separated element as a separate
* entry.
*
* @throws IOException
* if bad things happen during the read
*/
public String[] readNext() throws IOException {
String nextLine = getNextLine();
return hasNext ? parseLine(nextLine) : null;
}
/**
* Reads the next line from the file.
*
* @return the next line from the file without trailing newline
* @throws IOException
* if bad things happen during the read
*/
private String getNextLine() throws IOException {
if (!this.linesSkiped) {
for (int i = 0; i < skipLines; i++) {
br.readLine();
}
this.linesSkiped = true;
}
String nextLine = br.readLine();
if (nextLine == null) {
hasNext = false;
}
return hasNext ? nextLine : null;
}
/**
* Parses an incoming String and returns an array of elements.
*
* @param nextLine
* the string to parse
* @return the comma-tokenized list of elements, or null if nextLine is null
* @throws IOException
* if bad things happen during the read
*/
private String[] parseLine(String nextLine) throws IOException {
if (nextLine == null) {
return null;
}
List tokensOnThisLine = new ArrayList();
StringBuffer sb = new StringBuffer();
boolean inQuotes = false;
do {
if (inQuotes) {
// continuing a quoted section, reappend newline
sb.append("\n");
nextLine = getNextLine();
if (nextLine == null)
break;
}
for (int i = 0; i < nextLine.length(); i++) {
char c = nextLine.charAt(i);
if (c == quotechar) {
// this gets complex... the quote may end a quoted block, or
// escape another quote.
// do a 1-char lookahead:
if (inQuotes // we are in quotes, therefore there can be
// escaped quotes in here.
&& nextLine.length() > (i + 1) // there is indeed
// another character
// to check.
&& nextLine.charAt(i + 1) == quotechar) { // ..and
// that
// char.
// is a
// quote
// also.
// we have two quote chars in a row == one quote char,
// so consume them both and
// put one on the token. we do *not* exit the quoted
// text.
sb.append(nextLine.charAt(i + 1));
i++;
} else {
inQuotes = !inQuotes;
// the tricky case of an embedded quote in the middle:
// a,bc"d"ef,g
if (i > 2 // not on the begining of the line
&& nextLine.charAt(i - 1) != this.separator // not
// at
// the
// begining
// of
// an
// escape
// sequence
&& nextLine.length() > (i + 1)
&& nextLine.charAt(i + 1) != this.separator // not
// at
// the
// end
// of
// an
// escape
// sequence
) {
sb.append(c);
}
}
} else if (c == separator && !inQuotes) {
tokensOnThisLine.add(sb.toString());
sb = new StringBuffer(); // start work on next token
} else {
sb.append(c);
}
}
} while (inQuotes);
tokensOnThisLine.add(sb.toString());
return (String[]) tokensOnThisLine.toArray(new String[0]);
}
/**
* Closes the underlying reader.
*
* @throws IOException
* if the close fails
*/
public void close() throws IOException {
br.close();
}
}
读取测试类
public class CSVReaderTest {
CSVReader csvr;
/**
* Setup the test.
*/
@Before
public void init() throws Exception {
StringBuffer sb = new StringBuffer();
sb.append("a,b,c").append("\n"); // standard case
sb.append("a,\"b,b,b\",c").append("\n"); // quoted elements
sb.append(",,").append("\n"); // empty elements
sb.append("a,\"PO Box 123,\nKippax,ACT. 2615.\nAustralia\",d.\n");//Glen \"The Man\" Smith
sb.append("\"Glen \"\"The Man\"\" Smith\",Athlete,Developer\n"); // Test
// quoted
// quote
// chars
sb.append("\"\"\"\"\"\",\"test\"\n"); // """""","test" representing: "",
// test
sb.append("\"a\nb\",b,\"\nd\",e\n");
csvr = new CSVReader(new FileReader("d:/myfile.csv"));//这种方式就是读取文件了
//csvr = new CSVReader(new StringReader(sb.toString()));//这种方式就是读取字符串了
}
//测试读取文件
@Test
public void test1() throws IOException{
CSVReader c = new CSVReader(new FileReader("d:/myfile.csv"), ',',
'\"', 1);
String[] nextline=c.readNext();
System.out.println(nextline[0]);
assertEquals("CRM4005", nextline[0]);
}
/**
* Tests iterating over a reader.
*
* @throws IOException
* if the reader fails.
*/
public void ParseLine() throws IOException {
// test normal case //测试普通示例
String[] nextLine = csvr.readNext(); //第一行
assertEquals("a", nextLine[0]); //第一行第一个元素
assertEquals("b", nextLine[1]); //第一行第二个元素
assertEquals("c", nextLine[2]); //第一行第三个元素
// test quoted commas 测试引用起来的逗号
nextLine = csvr.readNext();
assertEquals("a", nextLine[0]);
assertEquals("b,b,b", nextLine[1]);
assertEquals("c", nextLine[2]);
// test empty elements 测试空元素
nextLine = csvr.readNext();
assertEquals(3, nextLine.length);
// test multiline quoted //测试多行引用的
nextLine = csvr.readNext();
assertEquals(3, nextLine.length);
// test quoted quote chars //测试引用起来的引号字符
nextLine = csvr.readNext();
assertEquals("Glen \"The Man\" Smith", nextLine[0]);
nextLine = csvr.readNext();
assertTrue(nextLine[0].equals("\"\"")); // check the tricky situation //检查复杂的位置
assertTrue(nextLine[1].equals("test")); // make sure we didn't ruin the
// next field.. 确保不破坏下一个域
nextLine = csvr.readNext();
assertEquals(4, nextLine.length);
// test end of stream 测试流的结尾
assertEquals(null, csvr.readNext());
}
/**
* Test parsing to a list.
*
* @throws IOException
* if the reader fails.
*/
@SuppressWarnings("unchecked")
public void testParseAll() throws IOException {
List allElements = csvr.readAll();
assertEquals(7, allElements.size());//应该指的是总共有多少行
}
/**
* Tests constructors with optional delimiters and optional quote char.
*
* @throws IOException
* if the reader fails.
*/
public void testOptionalConstructors() throws IOException {
StringBuffer sb = new StringBuffer();
sb.append("a\tb\tc").append("\n"); // tab separated case
sb.append("a\t'b\tb\tb'\tc").append("\n"); // single quoted elements
CSVReader c = new CSVReader(new StringReader(sb.toString()), '\t', '\'');
//上面的制定了分隔符为\t,指定了引号为单引号
String[] nextLine = c.readNext();
assertEquals(3, nextLine.length);
nextLine = c.readNext();
assertEquals(3, nextLine.length);
}
/**
* Tests option to skip the first few lines of a file.
*
* @throws IOException
* if bad things happen
*/
public void testSkippingLines() throws IOException {
StringBuffer sb = new StringBuffer();
sb.append("Skip this line\t with tab").append("\n"); // should skip this
sb.append("And this line too").append("\n"); // and this
sb.append("a\t'b\tb\tb'\tc").append("\n"); // single quoted elements
CSVReader c = new CSVReader(new StringReader(sb.toString()), '\t',
'\'', 2);//跳过两行来读取文本,那么读取的当然是第三行了
String[] nextLine = c.readNext();
assertEquals(3, nextLine.length);
assertEquals("a", nextLine[0]);
}
/**
* Tests quotes in the middle of an element.
*
* @throws IOException
* if bad things happen
*/
public void testParsedLineWithInternalQuota() throws IOException {
StringBuffer sb = new StringBuffer();
sb.append("a,123\"4\"567,c").append("\n");// a,123"4",c
CSVReader c = new CSVReader(new StringReader(sb.toString()));
String[] nextLine = c.readNext();
assertEquals(3, nextLine.length);
System.out.println(nextLine[1]);
assertEquals("123\"4\"567", nextLine[1]);
}
/**
* The Test Runner for commandline use.
*
* @param args
* no args required
*/
public static void main(String args[]) {
junit.textui.TestRunner.run(CSVReaderTest.class);//这个主要是用来测试继承自TestCase类的所有方法,并且方法名称那个以test开头,在此我没有继承所以这里报错正常
}
}
②CSV文件写入
文件写入操作类
public class CSVWriter {
private Writer rawWriter;
private PrintWriter pw;
private char separator;
private char quotechar;
private char escapechar;
private String lineEnd;
/** The character used for escaping quotes. */
public static final char DEFAULT_ESCAPE_CHARACTER = '"';
/** The default separator to use if none is supplied to the constructor. */
public static final char DEFAULT_SEPARATOR = ',';
/**
* The default quote character to use if none is supplied to the
* constructor.
*/
public static final char DEFAULT_QUOTE_CHARACTER = '"';
/** The quote constant to use when you wish to suppress all quoting. */
public static final char NO_QUOTE_CHARACTER = '\u0000';
/** The escape constant to use when you wish to suppress all escaping. */
public static final char NO_ESCAPE_CHARACTER = '\u0000';
/** Default line terminator uses platform encoding. */
public static final String DEFAULT_LINE_END = "\n";
private static final SimpleDateFormat TIMESTAMP_FORMATTER = new SimpleDateFormat(
"dd-MMM-yyyy HH:mm:ss");
private static final SimpleDateFormat DATE_FORMATTER = new SimpleDateFormat(
"dd-MMM-yyyy");
/**
* Constructs CSVWriter using a comma for the separator.
*
* @param writer
* the writer to an underlying CSV source.
*/
public CSVWriter(Writer writer) {
this(writer, DEFAULT_SEPARATOR);
}
/**
* Constructs CSVWriter with supplied separator.
*
* @param writer
* the writer to an underlying CSV source.
* @param separator
* the delimiter to use for separating entries.
*/
public CSVWriter(Writer writer, char separator) {
this(writer, separator, DEFAULT_QUOTE_CHARACTER);
}
/**
* Constructs CSVWriter with supplied separator and quote char.
*
* @param writer
* the writer to an underlying CSV source.
* @param separator
* the delimiter to use for separating entries
* @param quotechar
* the character to use for quoted elements
*/
public CSVWriter(Writer writer, char separator, char quotechar) {
this(writer, separator, quotechar, DEFAULT_ESCAPE_CHARACTER);
}
/**
* Constructs CSVWriter with supplied separator and quote char.
*
* @param writer
* the writer to an underlying CSV source.
* @param separator
* the delimiter to use for separating entries
* @param quotechar
* the character to use for quoted elements
* @param escapechar
* the character to use for escaping quotechars or escapechars
*/
public CSVWriter(Writer writer, char separator, char quotechar,
char escapechar) {
this(writer, separator, quotechar, escapechar, DEFAULT_LINE_END);
}
/**
* Constructs CSVWriter with supplied separator and quote char.
*
* @param writer
* the writer to an underlying CSV source.
* @param separator
* the delimiter to use for separating entries
* @param quotechar
* the character to use for quoted elements
* @param lineEnd
* the line feed terminator to use
*/
public CSVWriter(Writer writer, char separator, char quotechar,
String lineEnd) {
this(writer, separator, quotechar, DEFAULT_ESCAPE_CHARACTER, lineEnd);
}
/**
* Constructs CSVWriter with supplied separator, quote char, escape char and
* line ending.
*
* @param writer
* the writer to an underlying CSV source.
* @param separator
* the delimiter to use for separating entries
* @param quotechar
* the character to use for quoted elements
* @param escapechar
* the character to use for escaping quotechars or escapechars
* @param lineEnd
* the line feed terminator to use
*/
public CSVWriter(Writer writer, char separator, char quotechar,
char escapechar, String lineEnd) {
this.rawWriter = writer;
this.pw = new PrintWriter(writer);
this.separator = separator;
this.quotechar = quotechar;
this.escapechar = escapechar;
this.lineEnd = lineEnd;
}
/**
* Writes the entire list to a CSV file. The list is assumed to be a
* String[]
*
* @param allLines
* a List of String[], with each String[] representing a line of
* the file.
*/
@SuppressWarnings("unchecked")
public void writeAll(List allLines) {
for (Iterator iter = allLines.iterator(); iter.hasNext();) {
String[] nextLine = (String[]) iter.next();
writeNext(nextLine);
}
}
protected void writeColumnNames(ResultSetMetaData metadata)
throws SQLException {
int columnCount = metadata.getColumnCount();
String[] nextLine = new String[columnCount];
for (int i = 0; i < columnCount; i++) {
nextLine[i] = metadata.getColumnName(i + 1);
}
writeNext(nextLine);
}
/**
* Writes the entire ResultSet to a CSV file.
*
* The caller is responsible for closing the ResultSet.
*
* @param rs
* the recordset to write
* @param includeColumnNames
* true if you want column names in the output, false otherwise
*
*/
public void writeAll(java.sql.ResultSet rs, boolean includeColumnNames)
throws SQLException, IOException {
ResultSetMetaData metadata = rs.getMetaData();
if (includeColumnNames) {
writeColumnNames(metadata);
}
int columnCount = metadata.getColumnCount();
while (rs.next()) {
String[] nextLine = new String[columnCount];
for (int i = 0; i < columnCount; i++) {
nextLine[i] = getColumnValue(rs, metadata.getColumnType(i + 1),
i + 1);
}
writeNext(nextLine);
}
}
private static String getColumnValue(ResultSet rs, int colType, int colIndex)
throws SQLException, IOException {
String value = "";
switch (colType) {
case Types.BIT:
Object bit = rs.getObject(colIndex);
if (bit != null) {
value = String.valueOf(bit);
}
break;
case Types.BOOLEAN:
boolean b = rs.getBoolean(colIndex);
if (!rs.wasNull()) {
value = Boolean.valueOf(b).toString();
}
break;
case Types.CLOB:
Clob c = rs.getClob(colIndex);
if (c != null) {
value = read(c);
}
break;
case Types.BIGINT:
case Types.DECIMAL:
case Types.DOUBLE:
case Types.FLOAT:
case Types.REAL:
case Types.NUMERIC:
BigDecimal bd = rs.getBigDecimal(colIndex);
if (bd != null) {
value = "" + bd.doubleValue();
}
break;
case Types.INTEGER:
case Types.TINYINT:
case Types.SMALLINT:
int intValue = rs.getInt(colIndex);
if (!rs.wasNull()) {
value = "" + intValue;
}
break;
case Types.JAVA_OBJECT:
Object obj = rs.getObject(colIndex);
if (obj != null) {
value = String.valueOf(obj);
}
break;
case Types.DATE:
java.sql.Date date = rs.getDate(colIndex);
if (date != null) {
value = DATE_FORMATTER.format(date);
;
}
break;
case Types.TIME:
Time t = rs.getTime(colIndex);
if (t != null) {
value = t.toString();
}
break;
case Types.TIMESTAMP:
Timestamp tstamp = rs.getTimestamp(colIndex);
if (tstamp != null) {
value = TIMESTAMP_FORMATTER.format(tstamp);
}
break;
case Types.LONGVARCHAR:
case Types.VARCHAR:
case Types.CHAR:
value = rs.getString(colIndex);
break;
default:
value = "";
}
if (value == null) {
value = "";
}
return value;
}
private static String read(Clob c) throws SQLException, IOException {
StringBuffer sb = new StringBuffer((int) c.length());
Reader r = c.getCharacterStream();
char[] cbuf = new char[2048];
int n = 0;
while ((n = r.read(cbuf, 0, cbuf.length)) != -1) {
if (n > 0) {
sb.append(cbuf, 0, n);
}
}
return sb.toString();
}
/**
* Writes the next line to the file.
*
* @param nextLine
* a string array with each comma-separated element as a separate
* entry.
*/
public void writeNext(String[] nextLine) {
if (nextLine == null)
return;
StringBuffer sb = new StringBuffer();
for (int i = 0; i < nextLine.length; i++) {
if (i != 0) {
sb.append(separator);
}
String nextElement = nextLine[i];
if (nextElement == null)
continue;
if (quotechar != NO_QUOTE_CHARACTER)
sb.append(quotechar);
for (int j = 0; j < nextElement.length(); j++) {
char nextChar = nextElement.charAt(j);
if (escapechar != NO_ESCAPE_CHARACTER && nextChar == quotechar) {
sb.append(escapechar).append(nextChar);
} else if (escapechar != NO_ESCAPE_CHARACTER
&& nextChar == escapechar) {
sb.append(escapechar).append(nextChar);
} else {
sb.append(nextChar);
}
}
if (quotechar != NO_QUOTE_CHARACTER)
sb.append(quotechar);
}
sb.append(lineEnd);
pw.write(sb.toString());
}
/**
* Flush underlying stream to writer.
*
* @throws IOException
* if bad things happen
*/
public void flush() throws IOException {
pw.flush();
}
/**
* Close the underlying stream writer flushing any buffered content.
*
* @throws IOException
* if bad things happen
*
*/
public void close() throws IOException {
pw.flush();
pw.close();
rawWriter.close();
}
}
生成文件测试类
public class CSVWriterTest {
/**
* Test routine for converting output to a string.
*
* @param args
* the elements of a line of the cvs file
* @return a String version
* @throws IOException
* if there are problems writing
*/
private String invokeWriter(String[] args) throws IOException {
StringWriter sw = new StringWriter();
CSVWriter csvw = new CSVWriter(sw, ',', '\'');
csvw.writeNext(args);
return sw.toString();
}
/**
* Tests parsing individual lines.
*
* @throws IOException
* if the reader fails.
*/
public void testParseLine() throws IOException {
// test normal case
String[] normal = { "a", "b", "c" };
String output = invokeWriter(normal);
assertEquals("'a','b','c'\n", output);
// test quoted commas
String[] quoted = { "a", "b,b,b", "c" };
output = invokeWriter(quoted);
assertEquals("'a','b,b,b','c'\n", output);
// test empty elements
String[] empty = {,};
output = invokeWriter(empty);
assertEquals("\n", output);
// test multiline quoted
String[] multiline = { "This is a \n multiline entry", "so is \n this" };
output = invokeWriter(multiline);
assertEquals("'This is a \n multiline entry','so is \n this'\n", output);
}
/**
* Test parsing from to a list.
*
* @throws IOException
* if the reader fails.
*/
@SuppressWarnings("unchecked")
public void testParseAll() throws IOException {
List allElements = new ArrayList();
String[] line1 = "Name#Phone#Email".split("#");
String[] line2 = "Glen#1234#glen@abcd.com".split("#");
String[] line3 = "John#5678#john@efgh.com".split("#");
allElements.add(line1);
allElements.add(line2);
allElements.add(line3);
StringWriter sw = new StringWriter();
CSVWriter csvw = new CSVWriter(new FileWriter("d:/test.csv"), ',', '\'');
csvw.writeAll(allElements);
//String result = sw.toString();
//String[] lines = result.split("\n");
//assertEquals(3, lines.length);
}
/**
* Tests the option of having omitting quotes in the output stream.
*
* @throws IOException
* if bad things happen
*/
public void testNoQuoteChars() throws IOException {
String[] line = { "Foo", "Bar", "Baz" };
StringWriter sw = new StringWriter();
CSVWriter csvw = new CSVWriter(sw, CSVWriter.DEFAULT_SEPARATOR,
CSVWriter.NO_QUOTE_CHARACTER);
csvw.writeNext(line);
String result = sw.toString();
assertEquals("Foo,Bar,Baz\n", result);
}
/**
* Test null values.
*
* @throws IOException
* if bad things happen
*/
public void testNullValues() throws IOException {
String[] line = { "Foo", null, "Bar", "baz" };
StringWriter sw = new StringWriter();
CSVWriter csvw = new CSVWriter(sw);
csvw.writeNext(line);
String result = sw.toString();
assertEquals("\"Foo\",,\"Bar\",\"baz\"\n", result);
}
//@Test
//生成CSV文件
public void testStreamFlushing() throws IOException {
String WRITE_FILE = "d:/myfile.csv";
String[] nextLine = new String[] { "aaaa", "bbbb", "cccc", "dddd" };
FileWriter fileWriter = new FileWriter(WRITE_FILE);
CSVWriter writer = new CSVWriter(fileWriter);
writer.writeNext(nextLine);
// If this line is not executed, it is not written in the file.
writer.close();
}
public void testAlternateEscapeChar() {
String[] line = { "Foo", "bar's" };
StringWriter sw = new StringWriter();
CSVWriter csvw = new CSVWriter(sw, CSVWriter.DEFAULT_SEPARATOR,
CSVWriter.DEFAULT_QUOTE_CHARACTER, '\'');
csvw.writeNext(line);
assertEquals("\"Foo\",\"bar''s\"\n", sw.toString());
}
public void testNoQuotingNoEscaping() {
String[] line = { "\"Foo\",\"Bar\"" };
StringWriter sw = new StringWriter();
CSVWriter csvw = new CSVWriter(sw, CSVWriter.DEFAULT_SEPARATOR,
CSVWriter.NO_QUOTE_CHARACTER, CSVWriter.NO_ESCAPE_CHARACTER);
csvw.writeNext(line);
assertEquals("\"Foo\",\"Bar\"\n", sw.toString());
}
@Test
//测试嵌套的引号
public void testNestedQuotes() {
String[] data = new String[] { "\"\"", "test" };
String oracle = new String("\"\"\"\"\"\",\"test\"\n");
CSVWriter writer = null;
File tempFile = null;
FileWriter fwriter = null;
try {
tempFile = File.createTempFile("csvWriterTest", ".csv");
tempFile.deleteOnExit();
fwriter = new FileWriter(tempFile);
writer = new CSVWriter(fwriter);
} catch (IOException e) {
fail();
}
// write the test data:
writer.writeNext(data);
try {
writer.close();
} catch (IOException e) {
fail();
}
try {
// assert that the writer was also closed.
fwriter.flush();
fail();
} catch (IOException e) {
// we should go through here..
}
// read the data and compare.
FileReader in = null;
try {
in = new FileReader(tempFile);
} catch (FileNotFoundException e) {
fail();
}
StringBuffer fileContents = new StringBuffer();
try {
int ch;
while ((ch = in.read()) != -1) {
fileContents.append((char) ch);
}
in.close();
} catch (IOException e) {
fail();
}
assertTrue(oracle.equals(fileContents.toString()));
}
//@Test
public void testAlternateLineFeeds() {
String[] line = { "Foo", "Bar", "baz" };
StringWriter sw = new StringWriter();
CSVWriter csvw = new CSVWriter(sw, CSVWriter.DEFAULT_SEPARATOR,
CSVWriter.DEFAULT_QUOTE_CHARACTER, "\r");
csvw.writeNext(line);
String result = sw.toString();
assertTrue(result.endsWith("\r"));
}
/**
* The Test Runner for commandline use.
*
* @param args
* no args required
*/
public static void main(String args[]) {
junit.textui.TestRunner.run(CSVWriterTest.class);
}
}
其二:EXCEL文件的读取与生成(要用到jxl.jar, 上网可以搜到,我下面附上)
public class ExcelHandle {
public ExcelHandle() {
}
/**
* 读取Excel
*
* @param filePath
*/
public static void readExcel(String filePath) {
try {
InputStream is = new FileInputStream(filePath);
Workbook rwb = Workbook.getWorkbook(is);
// Sheet st = rwb.getSheet("0")这里有两种方法获取sheet表,1为名字,而为下标,从0开始
Sheet st = rwb.getSheet("original");
Cell c00 = st.getCell(0, 0);
// 通用的获取cell值的方式,返回字符串
String strc00 = c00.getContents();
// 获得cell具体类型值的方式
if (c00.getType() == CellType.LABEL) {
LabelCell labelc00 = (LabelCell) c00;
strc00 = labelc00.getString();
}
// 输出
System.out.println(strc00);
// 关闭
rwb.close();
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 输出Excel
*
* @param os
*/
public static void writeExcel(OutputStream os) {
try {
/**
* 只能通过API提供的工厂方法来创建Workbook,而不能使用WritableWorkbook的构造函数,
* 因为类WritableWorkbook的构造函数为protected类型
* method(1)直接从目标文件中读取WritableWorkbook wwb =
* Workbook.createWorkbook(new File(targetfile)); method(2)如下实例所示
* 将WritableWorkbook直接写入到输出流
*/
WritableWorkbook wwb = Workbook.createWorkbook(os);
// 创建Excel工作表 指定名称和位置
WritableSheet ws = wwb.createSheet("Test Sheet 1", 0);
// **************往工作表中添加数据*****************
// 1.添加Label对象
Label label = new Label(0, 0, "this is a label test");
ws.addCell(label);
// 添加带有字型Formatting对象
WritableFont wf = new WritableFont(WritableFont.TIMES, 18,
WritableFont.BOLD, true);
WritableCellFormat wcf = new WritableCellFormat(wf);
Label labelcf = new Label(1, 0, "this is a label test", wcf);
ws.addCell(labelcf);
// 添加带有字体颜色的Formatting对象
WritableFont wfc = new WritableFont(WritableFont.ARIAL, 10,
WritableFont.NO_BOLD, false, UnderlineStyle.NO_UNDERLINE,
jxl.format.Colour.RED);
WritableCellFormat wcfFC = new WritableCellFormat(wfc);
Label labelCF = new Label(1, 0, "This is a Label Cell", wcfFC);
ws.addCell(labelCF);
// 2.添加Number对象
Number labelN = new Number(0, 1, 3.1415926);
ws.addCell(labelN);
// 添加带有formatting的Number对象
NumberFormat nf = new NumberFormat("#.##");
WritableCellFormat wcfN = new WritableCellFormat(nf);
Number labelNF = new jxl.write.Number(1, 1, 3.1415926, wcfN);
ws.addCell(labelNF);
// 3.添加Boolean对象
Boolean labelB = new jxl.write.Boolean(0, 2, false);
ws.addCell(labelB);
// 4.添加DateTime对象
jxl.write.DateTime labelDT = new jxl.write.DateTime(0, 3,
new java.util.Date());
ws.addCell(labelDT);
// 添加带有formatting的DateFormat对象
DateFormat df = new DateFormat("dd MM yyyy hh:mm:ss");
WritableCellFormat wcfDF = new WritableCellFormat(df);
DateTime labelDTF = new DateTime(1, 3, new java.util.Date(), wcfDF);
ws.addCell(labelDTF);
// 添加图片对象,jxl只支持png格式图片
File image = new File("E:\\2.png");
WritableImage wimage = new WritableImage(0, 1, 2, 2, image);
ws.addImage(wimage);
// 写入工作表
wwb.write();
wwb.close();
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* 拷贝后,进行修改,其中file1为被copy对象,file2为修改后创建的对象
* 尽单元格原有的格式化修饰是不能去掉的,我们还是可以将新的单元格修饰加上去, 以使单元格的内容以不同的形式表现
*
* @param file1
* @param file2
*/
public static void modifyExcel(File file1, File file2) {
try {
Workbook rwb = Workbook.getWorkbook(file1);
WritableWorkbook wwb = Workbook.createWorkbook(file2, rwb);// copy
WritableSheet ws = wwb.getSheet(0);
WritableCell wc = ws.getWritableCell(0, 0);
// 判断单元格的类型,做出相应的转换
if (wc.getType() == CellType.LABEL) {
Label label = (Label) wc;
label.setString("The value has been modified");
}
wwb.write();
wwb.close();
rwb.close();
} catch (Exception e) {
e.printStackTrace();
}
}
// 测试
public static void main(String[] args) {
try {
// 读Excel
//ExcelHandle.readExcel("E:/testRead.xls");
// 输出Excel
File fileWrite = new File("E:/testWrite.xls");
fileWrite.createNewFile();
OutputStream os = new FileOutputStream(fileWrite);
ExcelHandle.writeExcel(os);
// 修改Excel
//ExcelHandle.modifyExcel(new File(""), new File(""));
} catch (Exception e) {
e.printStackTrace();
}
}
}
其三:读取CSV文件内容写入到Excel中(此代码含有同步数据库的操作)
public static void readCsv(String fileDir, Set targetSet) {
System.out.println("执行解析文件............");
try {
CSVReader csvr = new CSVReader(new FileReader(fileDir), ',', '\"',
1);
List allElements = csvr.readAll();
int size = allElements == null ? 0 : allElements.size();
System.out.println("总共有几行:" + size);
csvr = new CSVReader(new FileReader(fileDir), ',', '\"', 1);
String[] nextline = null;
File tempFile = new File("d:/output2.xls");//
WritableWorkbook workbook;
workbook = Workbook.createWorkbook(tempFile);
WritableSheet sheet = workbook.createSheet("kk", 1);
Label l = null;
WritableFont detFont = new WritableFont(WritableFont.ARIAL, 10,
WritableFont.NO_BOLD, false, UnderlineStyle.NO_UNDERLINE,
jxl.format.Colour.BLACK);
WritableCellFormat detFormat = new WritableCellFormat(detFont);
int column = 0;
l = new Label(column++, 0, "KPI_CODE", detFormat);
sheet.addCell(l);
l = new Label(column++, 0, "KPI_DESC", detFormat);
sheet.addCell(l);
l = new Label(column++, 0, "KPI_VALUE", detFormat);
sheet.addCell(l);
l = new Label(column++, 0, "KPI_MAX", detFormat);
sheet.addCell(l);
l = new Label(column++, 0, "KPI_MIN", detFormat);
sheet.addCell(l);
l = new Label(column++, 0, "MONTH_ID", detFormat);
sheet.addCell(l);
for (int i = 0; i < size; i++) {
TargetRecordPojo tp = new TargetRecordPojo();
nextline = csvr.readNext();
int len = nextline.length;
for (int j = 0; j < len; j++) {
l = new Label(j, i + 1, nextline[j], detFormat);
sheet.addCell(l);
if (j == 0) {
tp.setTarget_id(nextline[0]);
continue;
} else if (j == 1) {
tp.setRemark(nextline[1]);
continue;
} else if (j == 2) {
tp.setTarget_value(nextline[2]);
continue;
} else if (j == 3) {
tp.setTarget_data_max(nextline[3]);
continue;
} else if (j == 4) {
tp.setTarget_data_min(nextline[4]);
continue;
} else if (j == 5) {
tp.setTarget_date(nextline[5]);
// tp.setTarget_data_date(DateUtils.dateFormat(date));
continue;
}
}
targetSet.add(tp);
}
column = 0;
sheet.setColumnView(column++, 20);
sheet.setColumnView(column++, 20);
sheet.setColumnView(column++, 20);
sheet.setColumnView(column++, 20);
sheet.setColumnView(column++, 20);
sheet.setColumnView(column++, 20);
workbook.write();
workbook.close();
FileInputStream fis = new FileInputStream(tempFile);
FileOutputStream fos = new FileOutputStream(new File(
"d:/backupfile/backup_" + System.currentTimeMillis()
+ ".xls"));
byte[] buff = new byte[1024];
int len = -1;
while ((len = fis.read(buff)) != -1) {
fos.write(buff, 0, len);
}
fis.close();
fos.flush();
fos.close();
tempFile.delete();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (RowsExceededException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (WriteException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
- jxl.jar (708.7 KB)
- 下载次数: 43
发表评论
-
POI设置EXCEL单元格格式为文本、小数、百分比、货币、日期、科学计数法和中文大写
2011-01-25 11:07 79516再读本篇文章之前,请先看我的前一篇文章,前一篇文章中有重点讲到 ... -
POI对EXCEL的操作【重点:如何设置CELL格式为文本格式】
2011-01-25 10:07 80905实际开发过程中通常用到的就是从数据库导出EXCEL表格了,JX ... -
web网页上的文件下载功能
2010-11-18 16:00 12488首先提供下我的下载页面 那么要实现这么一种下载的话,t ... -
在IIS中设置默认的FTP目录
2010-10-19 10:13 2611【实现目标】 IIS的FTP目录默认是在“C:\inetpub ... -
Apache Common-Configuration的使用,重点介绍对XML和Properties的读取操作
2010-09-25 15:41 10008Apache Common-Configuration工具可以 ... -
关于JXL读写以及修改EXCEL文件
2010-07-29 09:08 14562首先引用网上的文章,谈谈JXL与POI的区别 POI为ap ... -
JAVA开发中POI和JXL区分
2010-07-27 10:48 7508java操作excel表格,以前只知道POI。POI是apac ... -
Java开发过程中文件上传的各种方式全面总结
2010-07-07 17:54 10025到目前为止:我接触到的有关上传的类型有这么几种JSP+Ser ... -
FTP远程上传下载文件
2010-05-25 22:21 5191最近工作中用到FTP知识,感觉比较好用,代码贴在下面 /* ... -
Java实现将Excel批量转换成txt
2010-05-24 06:24 6810有博友发信说要Excel转txt不成,这是因为没有准确的设置, ... -
Java IO流各种使用方式总结
2010-05-23 17:04 2814①针对普通文本的复 ... -
使用JAVA(iText)生成word(rtf)文档---内容可含图片哦
2010-03-24 15:58 22561当我使用这个JAVA生成RTF文件时费了好大的劲,原本是 ... -
lucene开发中有关读取pdf,html,word,rtf,txt,powerpoint,excel等文档的操作
2010-03-23 10:18 7578关于这七种文档,我相信应该是最常用的文档了 在以下的介绍中 ...
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