Java-類別庫-Guava-Throwables類-java教程-PHP中文網

Java-類別庫-Guava-Throwables類

黄舟

發布： 2017-01-19 13:25:39

原創

1656 人瀏覽過

有時候, 當我們我們捕獲異常, 並且像把這個異常傳遞到下一個try/catch塊中。 Guava提供了一個異常處理工具類, 可以簡單地捕獲和重新拋出多個異常。

[code]import java.io.IOException;
import org.junit.Test;
import com.google.common.base.Throwables;

public class ThrowablesTest {

    @Test
    public void testThrowables(){
        try {
            throw new Exception();
        } catch (Throwable t) {
            String ss = Throwables.getStackTraceAsString(t);
            System.out.println("ss:"+ss);
            Throwables.propagate(t);
        }
    }

    @Test
    public void call() throws IOException {
        try {
            throw new IOException();
        } catch (Throwable t) {
            Throwables.propagateIfInstanceOf(t, IOException.class);
            throw Throwables.propagate(t);
        }
    }    
}

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將檢查異常轉換成未檢查異常,例如：

[code]import java.io.InputStream;
import java.net.URL;
import org.junit.Test;
import com.google.common.base.Throwables;

public class ThrowablesTest {

    @Test
    public void testCheckException(){
        try {  
            URL url = new URL("http://ociweb.com");  
            final InputStream in = url.openStream();  
            // read from the input stream  
            in.close();  
        } catch (Throwable t) {  
            throw Throwables.propagate(t);  
        }  
    }
}

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　傳遞異常的常用方法：

　　1.RuntimeException propagate(Throwable)：把throwableceptionRuntimeException，用該方法保證一個異常傳遞異常值的異常

　　2.void propagateIfInstanceOf(Throwable, Class) throws X：當且僅當它是一個X的實例時，傳遞throwable

　　3.void propaic prodid propaic(Thwulwulwulwulwulwulwet Nelisconpaodid propaidable(Thr. ，傳遞throwable

　　4.void propagateIfPossible(Throwable, Class) throws X：當且僅當它是一個RuntimeException和Error時，或者是一個X的實例時，傳遞throwable。

[code]import java.io.IOException;
import org.junit.Test;
import com.google.common.base.Throwables;

public class ThrowablesTest {    
    @Test
    public void testThrowables(){
        try {
            throw new Exception();
        } catch (Throwable t) {
            String ss = Throwables.getStackTraceAsString(t);
            System.out.println("ss:"+ss);
            Throwables.propagate(t);
        }
    }

    @Test
    public void call() throws IOException {
        try {
            throw new IOException();
        } catch (Throwable t) {
            Throwables.propagateIfInstanceOf(t, IOException.class);
            throw Throwables.propagate(t);
        }
    }

    public Void testPropagateIfPossible() throws Exception {
          try {
              throw new Exception();
          } catch (Throwable t) {
            Throwables.propagateIfPossible(t, Exception.class);
            Throwables.propagate(t);
          }

          return null;
    }
}

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　Guava的異常鏈處理方法：

　　1.Throwable getRootCause(Throwable)

　　2.List getCausalChain(Throwable)以上就是Java-類別庫-Guava-Throwables類的內容，更多相關內容請關注PHP中文網（m.sbmmt.com）！